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What does phagocytosis defend the body from? | parasites | allergies | obesity | pathogens | 4. State how phagocytosis helps defend the body from pathogens. |
What measures the force of gravity pulling on an object? | velocity | density | volume | weight | Weight measures the force of gravity pulling on an object. The SI unit for weight is the Newton (N). |
Are coral reefs found in warm or cold water? | both | cool | cold | warm | Coral reefs are found only in warm water. Coal swamps are also found in tropical and subtropical environments. Wegener discovered ancient coal seams and coral reef fossils in areas that are much too cold today. Wegener thought that the continents have moved since the time of Pangaea. |
In humans, there are five primary tastes, and each taste has only one corresponding type of what? | membrane | organ | neuron | receptor | In humans, there are five primary tastes, and each taste has only one corresponding type of receptor. Thus, like olfaction, each receptor is specific to its stimulus (tastant). Transduction of the five tastes happens through different mechanisms that reflect the molecular composition of the tastant. A salty tastant (containing NaCl) provides the sodium ions (Na+) that enter the taste neurons and excite them directly. Sour tastants are acids and belong to the thermoreceptor protein family. Binding of an acid or other sour-tasting molecule triggers a change in the ion channel and these increase hydrogen ion (H+). |
The large positive free energy change leads to a value that is extremely what? | high | random | complex | small | The large positive free energy change leads to a value that is extremely small. Both lead to the conclusion that the reactants are highly favored and very few product molecules are present at equilibrium. |
Slime molds are fungus-like protists that grow as slimy masses on what? | dark matter | recycled matter | food matter | decaying matter | Slime molds are fungus-like protists that grow as slimy masses on decaying matter. They are commonly found on items such as rotting logs. |
What is the body cavity that reptiles have that is involved in reproduction? | ovules | hypothalamus | pristil | cloaca | Most reptiles have sexual reproduction with internal fertilization. Reptiles have a body cavity called a cloaca that is involved in reproduction. Sperm or eggs are released into an adult reptile’s cloaca. Males have one or two penises that pass sperm from their cloaca to the eggs in the cloaca of a female, where fertilization takes place. In most reptile species, once fertilized the eggs leave the body through an opening in the cloaca. These reptiles are oviparous. Eggs develop and hatch outside the mother’s body. |
What is the germ for a group of atoms within a molecule that reacts similarly anywhere it appears in different compounds? | molecular group | atomic group | thermal group | functional group | With over twenty million known organic compounds in existence, it would be very challenging to memorize chemical reactions for each one. Fortunately, molecules with similar functional groups tend to undergo similar reactions. A functional group is defined as an atom or group of atoms within a molecule that has similar chemical properties whenever it appears in various compounds. Even if other parts of the molecule are quite different, certain functional groups tend to react in certain ways. |
During asexual reproduction, fungi produce haploid spores by what process involving a haploid parent cell? | divergence | osmosis | evaporation | mitosis | During asexual reproduction, fungi produce haploid spores by mitosis of a haploid parent cell. A haploid cell has just one of each pair of chromosomes. The haploid spores are genetically identical to the parent cell. Spores may be spread by moving water, wind, or other organisms. Wherever the spores land, they will develop into new hyphae only when conditions are suitable for growth. |
In eukaryotes, oxidative phosphorylation takes place in what? | nucleus | glucose | lipids | mitochondria | Figure 7.5 In eukaryotes, oxidative phosphorylation takes place in mitochondria. In prokaryotes, this process takes place in the plasma membrane. (Credit: modification of work by Mariana Ruiz Villareal). |
Short chains of two amino acids (dipeptides) or three amino acids (tripeptides) are also transported actively. however, after they enter the absorptive epithelial cells, they are broken down into their amino acids before leaving the cell and entering the capillary blood via what? | absorption | osmosis | convection | diffusion | transports an amino acid varies. Most carriers are linked to the active transport of sodium. Short chains of two amino acids (dipeptides) or three amino acids (tripeptides) are also transported actively. However, after they enter the absorptive epithelial cells, they are broken down into their amino acids before leaving the cell and entering the capillary blood via diffusion. |
What do fungi use to penetrate deep into decaying matter? | flagella | cilia | cytoplasm | hyphae | Most fungi get organic compounds from dead organisms. Fungi use their hyphae to penetrate deep into decaying organic matter. They produce enzymes at the tips of their hyphae. The enzymes digest the organic matter so the fungal cells can absorb it. Fungi are the main decomposers in forests. They are the only decomposers that can break down cellulose and wood. They have special enzymes for this purpose. |
All living cells in multicellular organisms contain an internal cytoplasmic compartment, and a nucleus within the cytoplasm. cytosol, the jelly-like substance within the cell, provides the fluid medium necessary for this? | apoptosis | meiosis | cell division | biochemical reactions | Now that you have learned that the cell membrane surrounds all cells, you can dive inside of a prototypical human cell to learn about its internal components and their functions. All living cells in multicellular organisms contain an internal cytoplasmic compartment, and a nucleus within the cytoplasm. Cytosol, the jelly-like substance within the cell, provides the fluid medium necessary for biochemical reactions. Eukaryotic cells, including all animal cells, also contain various cellular organelles. An organelle (“little organ”) is one of several different types of membrane-enclosed bodies in the cell, each performing a unique function. Just as the various bodily organs work together in harmony to perform all of a human’s functions, the many different cellular organelles work together to keep the cell healthy and performing all of its important functions. The organelles and cytosol, taken together, compose the cell’s cytoplasm. The nucleus is a cell’s central organelle, which contains the cell’s DNA (Figure 3.13). |
Under appropriate conditions, the attractions between all molecules in what state will cause them to form liquids or solids? | liquid | soild | plasma | gas | Forces between Molecules Under appropriate conditions, the attractions between all gas molecules will cause them to form liquids or solids. This is due to intermolecular forces, not intramolecular forces. Intramolecular forces are those within the molecule that keep the molecule together, for example, the bonds between the atoms. Intermolecular forces are the attractions between molecules, which determine many of the physical properties of a substance. Figure 10.5 illustrates these different molecular forces. The strengths of these attractive forces vary widely, though usually the IMFs between small molecules are weak compared to the intramolecular forces that bond atoms together within a molecule. For example, to overcome the IMFs in one mole of liquid HCl and convert it into gaseous HCl requires only about 17 kilojoules. However, to break the covalent bonds between the hydrogen and chlorine atoms in one mole of HCl requires about 25 times more energy—430 kilojoules. |
What else besides temperature has an effect on the phase of a substance? | energy | weight | resistance | pressure | Butter is a fat that is a solid at room temperature. What type of fatty acid does butter contain? How do you know?. |
What type of charge does a neutron have? | half charge | negative charge | positive charge | neutral or no charge | three building blocks of most matter. (The third is the neutron, which is neutral, carrying no charge. ) Other charge-carrying particles are observed in cosmic rays and nuclear decay, and are created in particle accelerators. All but the electron and proton survive only a short time and are quite rare by comparison. |
Animals that molt their exoskeletons belong to which clade? | trichina | protists | spirogyra | ecdysozoa | Figure 27.13 Animals that molt their exoskeletons, such as these (a) Madagascar hissing cockroaches, are in the clade Ecdysozoa. (b) Phoronids are in the clade Lophotrochozoa. The tentacles are part of a feeding structure called a lophophore. (credit a: modification of work by Whitney Cranshaw, Colorado State University, Bugwood. org; credit b: modification of work by NOAA). |
Alkaline earth metals are what color? | reddish orange | white | black | silvery grey | The alkaline Earth metals include all the elements in group 2 (see Figure below ). These metals have just two valence electrons, so they are very reactive, although not quite as reactive as the alkali metals. In nature, they are always found combined with other elements. Alkaline Earth metals are silvery grey in color. They are harder and denser than the alkali metals. All are solids at room temperature. |
What type of movement is caused by erosion from direct gravity? | electron movement | frictional movement | normal movement | mass movement | Outline the forces that act on particles in the nucleus. |
What term is used describe energy released during an earthquake? | resonance | blast | seismic load | magnitude | For decades scientists have had equipment that can measure earthquake magnitude. The earthquake magnitude is the energy released during the quake. |
What are the rolling motions during an earthquake called? | velocity waves | tidal waves | seismic thrusts | surface waves | There are two major types of seismic waves. Body waves travel through the Earth’s interior. Surface waves travel along the ground surface. In an earthquake, body waves are responsible for the sharp jolts. Surface waves are responsible for the rolling motions that do most of the damage in an earthquake. |
What is the process that breaks down rocks into smaller pieces? | bleaching | erosion | bracing | weathering | |
What is the measurement for the amount of water vapor in the air? | saturation | haze | ambient | humidity | A: Humidity is a measure of the amount of water vapor in the air. When humidity is high, sweat evaporates more slowly because there is already a lot of water vapor in the air. The slower evaporation rate reduces the potential for evaporative cooling. |
Major exchange pools of carbon include organisms and what else? | the intensity | location | duration | the atmosphere | Major exchange pools of carbon include organisms and the atmosphere. Carbon cycles more quickly between these components of the carbon cycle. |
When light is absorbed by a material, what may increase? | mass | happiness | weight | its temperature | Light may be absorbed by matter. This is called absorption of light. When light is absorbed, it doesn’t reflect from or pass through matter. Instead, its energy is transferred to particles of matter, which may increase the temperature of matter. |
What branch of physical science looks at how heat, work, and various forms of energy are related to one another? | transformations | photosynthesis | frigidity | thermodynamics | Just as the burning of wood releases energy in the form of heat, many other chemical reactions also release heat. There are also chemical reactions, such as photosynthesis in plants, which absorb energy in the form of heat. The study of energy changes in chemical reactions is called thermochemistry . The broader term thermodynamics also looks at how heat, work, and various forms of energy are related to one another. In this lesson, we will study the difference between reactions that absorb versus release heat as well as how to measure this change in energy. |
Connective tissues typically have three characteristic components in common: cells, large amounts of amorphous ground substance, and what else? | white blood cells | antioxidants | hormones | protein fibers | 4.3 | Connective Tissue Supports and Protects By the end of this section, you will be able to: • Identify and distinguish between the types of connective tissue: proper, supportive, and fluid • Explain the functions of connective tissues As may be obvious from its name, one of the major functions of connective tissue is to connect tissues and organs. Unlike epithelial tissue, which is composed of cells closely packed with little or no extracellular space in between, connective tissue cells are dispersed in a matrix. The matrix usually includes a large amount of extracellular material produced by the connective tissue cells that are embedded within it. The matrix plays a major role in the functioning of this tissue. The major component of the matrix is a ground substance often crisscrossed by protein fibers. This ground substance is usually a fluid, but it can also be mineralized and solid, as in bones. Connective tissues come in a vast variety of forms, yet they typically have in common three characteristic components: cells, large amounts of amorphous ground substance, and protein fibers. The amount and structure of each component correlates with the function of the tissue, from the rigid ground substance in bones supporting the body to the inclusion of specialized cells; for example, a phagocytic cell that engulfs pathogens and also rids tissue of cellular debris. |
After what stage do the last 2 stages of food processing occur? | circulation | filtration | excretion | digestion | |
What part of the plant holds the plant upright? | notochord | roots | leaves | the stem | Stems hold plants upright, bear leaves and other structures, and transport fluids between roots and leaves. Like roots, stems contain dermal, ground, and vascular tissues. Trees have woody stems covered with bark. |
What is a circuit that consists of one loop called? | dramatic circuit | speaking circuit | episode circuit | series circuit | A circuit that consists of one loop is called a series circuit. If its single loop is interrupted at any point, no current can flow through the circuit. |
Leaves respond to these environmental stimuli by producing less what? | energy | oxygen | carbonate | chlorophyll | Vertebrates have a closed circulatory system with a heart. Blood is completely contained within blood vessels that carry the blood throughout the body. The heart is divided into chambers that work together to pump blood. There are between two and four chambers in the vertebrate heart. With more chambers, there is more oxygen in the blood and more vigorous pumping action. |
Mammals that lay eggs are called what? | marsupial | viviparous | herbivores | monotremes | Mammals have separate sexes and reproduce sexually. They produce eggs or sperm and must mate in order for fertilization to occur. A few mammals are oviparous. They lay eggs, which later hatch. These mammals are called monotremes. Most mammals are viviparous and give birth to live young. These mammals are either placental mammals or marsupials. Placental mammals give birth to relatively large and well-developed fetuses. Marsupials give birth to smaller, less-developed embryos. In both placental and marsupial mammals, the young grow and develop inside the mother’s body in an organ called the uterus. At birth, they pass through a tube-like organ called the birth canal, or vagina. |
In what ocean is the mid-atlantic ridge located? | arctic ocean | indian ocean | pacific ocean | atlantic ocean | There is a lot of volcanic activity at divergent plate boundaries in the oceans. As the plates pull away from each other, they create deep fissures. Molten lava erupts through these cracks. The East Pacific Rise is a divergent plate boundary in the Pacific Ocean ( Figure below ). The Mid-Atlantic Ridge is a divergent plate boundary in the Atlantic Ocean. |
Models may be physical, conceptual, or what else? | theoretical | experimental | fundamental | mathematical | Models may be physical, conceptual, or mathematical. |
What is an organism that spreads bacteria or other pathogens? | arc | plane | section | vector | Some bacteria are spread by vectors. A vector is an organism that spreads bacteria or other pathogens. Most vectors are animals, commonly insects. For example, deer ticks like the one in Figure below spread Lyme disease. Ticks carry Lyme disease bacteria from deer to people when they bite them. |
What influences the types of plants and animals that inhabit a specific biome? | cooling | carbon | Water | climate | Climate influences the types of plants and animals that inhabit a specific biome. |
In the vast majority of ectopic pregnancies, the embryo does not complete its journey to what organ, and instead implants in the uterine tube? | vagina | stomach | ovaries | uterus | Development of the Embryo In the vast majority of ectopic pregnancies, the embryo does not complete its journey to the uterus and implants in the uterine tube, referred to as a tubal pregnancy. However, there are also ovarian ectopic pregnancies (in which the egg never left the ovary) and abdominal ectopic pregnancies (in which an egg was “lost” to the abdominal cavity during the transfer from ovary to uterine tube, or in which an embryo from a tubal pregnancy re-implanted in the abdomen). Once in the abdominal cavity, an embryo can implant into any well-vascularized structure—the rectouterine cavity (Douglas’ pouch), the mesentery of the intestines, and the greater omentum are some common sites. Tubal pregnancies can be caused by scar tissue within the tube following a sexually transmitted bacterial infection. The scar tissue impedes the progress of the embryo into the uterus—in some cases “snagging” the embryo and, in other cases, blocking the tube completely. Approximately one half of tubal pregnancies resolve spontaneously. Implantation in a uterine tube causes bleeding, which appears to stimulate smooth muscle contractions and expulsion of the embryo. In the remaining cases, medical or surgical intervention is necessary. If an ectopic pregnancy is detected early, the embryo’s development can be arrested by the administration of the cytotoxic drug methotrexate, which inhibits the metabolism of folic acid. If diagnosis is late and the uterine tube is already ruptured, surgical repair is essential. Even if the embryo has successfully found its way to the uterus, it does not always implant in an optimal location (the fundus or the posterior wall of the uterus). Placenta previa can result if an embryo implants close to the internal os of the uterus (the internal opening of the cervix). As the fetus grows, the placenta can partially or completely cover the opening of the cervix (Figure 28.7). Although it occurs in only 0.5 percent of pregnancies, placenta previa is the leading cause of antepartum hemorrhage (profuse vaginal bleeding after week 24 of pregnancy but prior to childbirth). |
In a single-celled organism such as chlamydomonas, there is no what after fertilization? | meiosis | germination | spawning | mitosis | Reproduction of Green Algae Green algae reproduce both asexually, by fragmentation or dispersal of spores, or sexually, by producing gametes that fuse during fertilization. In a single-celled organism such as Chlamydomonas, there is no mitosis after fertilization. In the multicellular Ulva, a sporophyte grows by mitosis after fertilization. Both Chlamydomonas and Ulva produce flagellated gametes. |
Timber, medicines, dyes, oils, and rubber are just some of the useful products humans derive from what? | flowers | roots | fossils | plants | Plants provide many products for human use. They include timber, medicines, dyes, oils, and rubber. |
Differences between organisms reflect differences between their nucleotide sequences rather than between their what? | environments | molecular codes | amino acids | genetic codes | |
Lying with their mouths open, a behavior called gaping, probably serves what function for crocodiles? | eating | sleeping | digesting | cooling down | All crocodilians have, like humans, teeth set in bony sockets. But unlike mammals, they replace their teeth throughout life. Crocodiles and gharials (large crocodilians with longer jaws) have salivary glands on their tongue, which are used to remove salt from their bodies. This helps with life in a saltwater environment. Crocodilians are often seen lying with their mouths open, a behavior called gaping . One of its functions is probably to cool them down. |
What type of living things break down dead organisms and recycle their nutrients into the soil? | probiotics | producers | consumers | decomposers | |
When food enters the stomach after a period of fasting, a drop in what initiates the conversion of pepsinogen to pepsin? | acid | calcium | white blood cells | ph | produced in cells located in the stomach wall. When food enters the stomach after a period of fasting, pepsinogen is converted to its active form—pepsin—in a series of steps initiated by the drop in pH. Pepsin catalyzes the hydrolysis of peptide linkages within protein molecules. It has a fairly broad specificity but acts preferentially on linkages involving the aromatic amino acids tryptophan, tyrosine, and phenylalanine, as well as methionine and leucine. Protein digestion is completed in the small intestine. Pancreatic juice, carried from the pancreas via the pancreatic duct, contains inactive enzymes such as trypsinogen and chymotrypsinogen. They are activated in the small intestine as follows (Figure 20.7 "Activation of Some Pancreatic Enzymes in the Small Intestine"): The intestinal mucosal cells secrete the proteolytic enzyme enteropeptidase, which converts trypsinogen to trypsin; trypsin then activates chymotrypsinogen to chymotrypsin (and also completes the activation of trypsinogen). Both of these active enzymes catalyze the hydrolysis of peptide bonds in protein chains. Chymotrypsin preferentially attacks peptide bonds involving the carboxyl groups of the aromatic amino acids (phenylalanine, tryptophan, and tyrosine). Trypsin attacks peptide bonds involving the carboxyl groups of the basic amino acids (lysine and arginine). Pancreatic juice also contains procarboxypeptidase, which is cleaved by trypsin to carboxypeptidase. The latter is an enzyme that catalyzes the hydrolysis of peptide linkages at the free carboxyl end of the peptide chain, resulting in the stepwise liberation of free amino acids from the carboxyl end of the polypeptide. Figure 20.7 Activation of Some Pancreatic Enzymes in the Small Intestine. |
Mutations that lead to cancer usually occur in genes that control the cell cycle. these include tumor-suppressor genes and what? | Darkness Oncogenes | extinction - oncogenes | apparition - oncogenes | proto-oncogenes | Mutations that lead to cancer usually occur in genes that control the cell cycle. These include tumor-suppressor genes and proto-oncogenes. |
What type of environment is maintained in homeostasis? | stable external | fluid internal | noisy internal | constant internal | Homeostasis is maintaining a constant internal environment. |
When calculating impulse, consider the change in _______ of one of the objects in the collision? | velocity | sound | potential energy | momentum | the initial momentum of an object. When calculating impulse, consider the change in momentum of one of the objects in the collision. |
What word describes any chemical that affects the body’s structure or function? | gift | treatment | toxin | drug | A drug is any chemical that affects the body’s structure or function. Many drugs, including both legal and illegal drugs, are psychoactive drugs . This means that they affect the central nervous system, generally by influencing the transmission of nerve impulses. For example, some psychoactive drugs mimic neurotransmitters. At the link below, you can watch an animation showing how psychoactive drugs affect the brain. http://www. thirteen. org/closetohome/animation/neuron-main. html. |
The entry of acidic chyme into the duodenum stimulates the release of what? | oxygen | progesterone | gastrin | secretin | Pancreatic Secretion Regulation of pancreatic secretion is the job of hormones and the parasympathetic nervous system. The entry of acidic chyme into the duodenum stimulates the release of secretin, which in turn causes the duct cells to release bicarbonaterich pancreatic juice. The presence of proteins and fats in the duodenum stimulates the secretion of CCK, which then stimulates the acini to secrete enzyme-rich pancreatic juice and enhances the activity of secretin. Parasympathetic regulation occurs mainly during the cephalic and gastric phases of gastric secretion, when vagal stimulation prompts the secretion of pancreatic juice. Usually, the pancreas secretes just enough bicarbonate to counterbalance the amount of HCl produced in the stomach. Hydrogen ions enter the blood when bicarbonate is secreted by the pancreas. Thus, the acidic blood draining from the pancreas neutralizes the alkaline blood draining from the stomach, maintaining the pH of the venous blood that flows to the liver. |
Adulthood is divided into how many stages? | five | two | four | three | Adulthood is divided into the stages of early, middle, and late adulthood. |
What is the single bone that forms the posterior skull and posterior base of the cranial cavity? | radiating bone | limbic bone | maxilla | occipital bone | Occipital Bone The occipital bone is the single bone that forms the posterior skull and posterior base of the cranial cavity (Figure 7.9; see also Figure 7.8). On its outside surface, at the posterior midline, is a small protrusion called the external occipital protuberance, which serves as an attachment site for a ligament of the posterior neck. Lateral to either side of this bump is a superior nuchal line (nuchal = “nape” or “posterior neck”). The nuchal lines represent the most superior point at which muscles of the neck attach to the skull, with only the scalp covering the skull above these lines. On the base of the skull, the occipital bone contains the large opening of the foramen magnum, which allows for passage of the spinal cord as it exits the skull. On either side of the foramen magnum is an oval-shaped occipital condyle. These condyles form joints with the first cervical vertebra and thus support the skull on top of the vertebral column. |
Is the progeny produced by asexual reproduction stronger or weaker than seedlings produced by sexual reproduction? | weaker | the same | lighter | stronger | |
Supersaturated solutions of most solids in water are prepared by cooling what? | plasma solutions | mineral solutions | dense solutions | saturated solutions | (b) Write a balanced chemical equation showing the products of the dissolution of Fe(NO3)3. Compare the processes that occur when methanol (CH3OH), hydrogen chloride (HCl), and sodium hydroxide (NaOH) dissolve in water. Write equations and prepare sketches showing the form in which each of these compounds is present in its respective solution. What is the expected electrical conductivity of the following solutions? (a) NaOH(aq) (b) HCl(aq) (c) C6H12O6(aq) (glucose) (d) NH3(l) 14. Why are most solid ionic compounds electrically nonconductive, whereas aqueous solutions of ionic compounds are good conductors? Would you expect a liquid (molten) ionic compound to be electrically conductive or nonconductive? Explain. Indicate the most important type of intermolecular attraction responsible for solvation in each of the following solutions: (a) the solutions in Figure 11.8 (b) methanol, CH3OH, dissolved in ethanol, C2H5OH (c) methane, CH4, dissolved in benzene, C6H6 (d) the polar halocarbon CF2Cl2 dissolved in the polar halocarbon CF2ClCFCl2 (e) O2(l) in N2(l) 11.3 Solubility 16. Suppose you are presented with a clear solution of sodium thiosulfate, Na2S2O3. How could you determine whether the solution is unsaturated, saturated, or supersaturated? 17. Supersaturated solutions of most solids in water are prepared by cooling saturated solutions. Supersaturated solutions of most gases in water are prepared by heating saturated solutions. Explain the reasons for the difference in the two procedures. Suggest an explanation for the observations that ethanol, C2H5OH, is completely miscible with water and that ethanethiol, C2H5SH, is soluble only to the extent of 1.5 g per 100 mL of water. Calculate the percent by mass of KBr in a saturated solution of KBr in water at 10 °C. See Figure 11.17 for useful data, and report the computed percentage to one significant digit. Which of the following gases is expected to be most soluble in water? Explain your reasoning. (a) CH4 (b) CCl4. |
Bacterial stis usually can be cured with what? | antiviral drugs | pesticides | antioxidants | antibiotics | Bacterial STIs usually can be cured with antibiotics. |
Intensity is defined to be the power per unit area carried by a what? | wire | filament | shift | wave | Intensity is defined to be the power per unit area carried by a wave. Power is the rate at which energy is transferred by the wave. In equation form, intensity I is. |
Trophic level 4 = tertiary consumers that eat what kind of consumers? | primary consumers | insects | herbivores | secondary consumers | Trophic level 4 = tertiary consumers that eat secondary consumers. |
What takes the shape of the container they are placed in and have a definite volume? | loads | gases | solids | liquids | |
What is produced when a colorless solution of lead nitrate is added to a colorless solution of potassium iodide? | purple solid precipitate | blue solid precipitate | brown solid precipitate | yellow solid precipitate | When a colorless solution of lead(II) nitrate is added to a colorless solution of potassium iodide, a yellow solid called a precipitate is instantly produced ( Figure below ). A precipitate is a solid product that forms from a reaction and settles out of a liquid mixture. The formation of a precipitate may also indicate the occurrence of a chemical reaction. |
Due to the difference in the distribution of charge, water is what type of molecule? | crooked | ionic | uneven | polar | Due to the difference in the distribution of charge, water is a polar molecule. |
What do we call the major artery carrying recently oxygenated blood away from the heart? | arteriole | capillary | muscular artery | aorta | Arterial Supply The major artery carrying recently oxygenated blood away from the heart is the aorta. The very first branches off the aorta supply the heart with nutrients and oxygen. The next branches give rise to the common carotid arteries, which further branch into the internal carotid arteries. The external carotid arteries supply blood to the tissues on the surface of the cranium. The bases of the common carotids contain stretch receptors that immediately respond to the drop in blood pressure upon standing. The orthostatic reflex is a reaction to this change in body position, so that blood pressure is maintained against the increasing effect of gravity (orthostatic means “standing up”). Heart rate increases—a reflex of the sympathetic division of the autonomic nervous system—and this raises blood pressure. |
In a model of a hemoglobin molecule, the purple part indicates the presence of what element? | silver | gold | helium | iron | Hemoglobin Molecule. This model represents the protein hemoglobin. The purple part of the molecule contains iron. The iron binds with oxygen molecules. |
What kind of gland produces an oily substance that waterproofs the hair and skin? | mucous gland | secretion gland | nail gland | sebaceous gland | oily substance produced in the dermis by a sebaceous gland that waterproofs the hair and skin. |
Which type of substance is considered a proton donor in a reaction? | oxygen | base | carbon | acid | The Arrhenius definition of acids and bases is somewhat limited. There are some compounds whose properties suggest that they are either acidic or basic, but which do not qualify according to the Arrhenius definition. An example is ammonia (NH 3 ). Its aqueous solution turns litmus blue, it reacts with acids, and displays all the other properties of a base. However, it does not contain the hydroxide ion. In 1923, a broader definition of acids and bases was independently proposed by Danish chemist Johannes Brønsted (1879-1947) and English chemist Thomas Lowry (1874-1936). A Brønsted-Lowry acid is a molecule or ion that donates a hydrogen ion in a reaction. A Brønsted-Lowry base is a molecule or ion that accepts a hydrogen ion in a reaction. A hydrogen ion is commonly referred to as a proton, and so acids and bases are proton donors and proton acceptors respectively according to the Brønsted-Lowry definition. All substances that are categorized as acids and bases under the Arrhenius definition are also defined as such under the Brønsted-Lowry definition. The new definition, however, includes some substances that are left out according to the Arrhenius definition. |
What are materials that are good conductors of thermal energy called? | geospatial conductors | reflective conductors | atmospheric conductors | thermal conductors | Conduction is usually faster in liquids and certain solids than in gases. Materials that are good conductors of thermal energy are called thermal conductors . Metals are excellent thermal conductors. They have freely moving electrons that can transfer energy quickly and easily. That’s why the metal pot in Figure above soon gets hot all over, even though it gains thermal energy from the fire only at the bottom of the pot. In Figure below , the metal heating element of the curling iron heats up almost instantly and quickly transfers energy to the strands of hair that it touches. |
Why do players with more mass often have a larger impact in football? | Velocity is larger | potential energy is lower | kinetic energy is lower | momentum is larger | Figure 28.18 Momentum is an important concept for these football players from the University of California at Berkeley and the University of California at Davis. Players with more mass often have a larger impact because their momentum is larger. For objects moving at relativistic speeds, the effect is even greater. (credit: John Martinez Pavliga). |
Corals build hard exoskeletons that grow to become what? | fungi | algae | stability reefs | coral reefs | |
What property is the result of force acting on a given area? | resistance | vaccuum | pull | pressure | Pressure is the result of force acting on a given area. It can be represented by the equation:. |
Nervous tissue consists of just two basic types of nerve cells: neurons and? | mammalian cells | white blood cells | red blood cells | glial cells | Although the nervous system is very complex, nervous tissue consists of just two basic types of nerve cells: neurons and glial cells. Neurons are the structural and functional units of the nervous system. They transmit electrical signals, called nerve impulses. Glial cells provide support for neurons. For example, they provide neurons with nutrients and other materials. |
The plasma membrane of a skeletal muscle fiber is called the what? | soleus | sheath | annulata | sarcolemma | Skeletal Muscle Fiber Structure Each skeletal muscle fiber is a skeletal muscle cell. These cells are incredibly large, with diameters of up to 100 µm and lengths of up to 30 cm. The plasma membrane of a skeletal muscle fiber is called the sarcolemma. The sarcolemma is the site of action potential conduction, which triggers muscle contraction. Within each muscle fiber are myofibrils—long cylindrical structures that lie parallel to the muscle fiber. Myofibrils run the entire length of the muscle fiber, and because they are only approximately 1.2 µm in diameter, hundreds to thousands can be found inside one muscle fiber. They attach to the sarcolemma at their ends, so that as myofibrils shorten, the entire muscle cell contracts (Figure 38.34). |
What is the force pulling an object downward called? | magnetism | momentum | density | weight | The weight of an object is the force pulling the object downward. On Earth, this would be the gravitational force of the Earth on the object. On the moon, this would be the gravitational force of the moon on the object. The gravitational force of the moon is one-sixth the magnitude of the gravitational force of the Earth; the weight of the moon rock on the moon will be one-sixth the weight of the moon rock on the Earth’s surface. Weight is measured in force units—newtons—by a calibrated spring scale as shown here. |
Which part of all mammals have the same basic bone structure? | necks | ankles | knees | forelimbs | The forelimbs of all mammals have the same basic bone structure. |
The symbol for each what is usually the first letter or two of its name? | material | state | property | element | |
The only things that affect the period of a simple pendulum are its length and the acceleration due to gravity. the period is completely independent of other factors, such as this? | speed | size | rate | mass | for the period of a simple pendulum. This result is interesting because of its simplicity. The only things that affect the period of a simple pendulum are its length and the acceleration due to gravity. The period is completely independent of other factors, such as mass. As with simple harmonic oscillators, the period T for a pendulum is nearly independent of amplitude, especially if θ is less than about. |
What is the amide bond that occurs between the amino nitrogen of one amino acid and the carboxyl carbon of another amino acid? | a amino bond | a covalent bond | a magnetite bond | a peptide bond | A peptide bond is the amide bond that occurs between the amino nitrogen of one amino acid and the carboxyl carbon of another amino acid. The resulting molecule is called a dipeptide. Notice that the particular side chains of each amino acid are irrelevant since the R groups are not involved in the peptide bond. |
What encloses the border of animal cells? | cells membrane | Jacket membrane | dust membrane | plasma membrane | 3.4 | The Cell Membrane By the end of this section, you will be able to: • Understand the fluid mosaic model of membranes • Describe the functions of phospholipids, proteins, and carbohydrates in membranes A cell’s plasma membrane defines the boundary of the cell and determines the nature of its contact with the environment. Cells exclude some substances, take in others, and excrete still others, all in controlled quantities. Plasma membranes enclose the borders of cells, but rather than being a static bag, they are dynamic and constantly in flux. The plasma membrane must be sufficiently flexible to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. These are the more obvious functions of a plasma membrane. In addition, the surface of the plasma membrane carries markers that allow cells to recognize one another, which is vital as tissues and organs form during early development, and which later plays a role in the “self” versus “non-self” distinction of the immune response. The plasma membrane also carries receptors, which are attachment sites for specific substances that interact with the cell. Each receptor is structured to bind with a specific substance. For example, surface receptors of the membrane create changes in the interior, such as changes in enzymes of metabolic pathways. These metabolic pathways might be vital for providing the cell with energy, making specific substances for the cell, or breaking down cellular waste or toxins for disposal. Receptors on the plasma membrane’s exterior surface interact with hormones or neurotransmitters, and allow their messages to be transmitted into the cell. Some recognition sites are used by viruses as attachment points. Although they are highly specific, pathogens like viruses may evolve to exploit receptors to gain entry to a cell by mimicking the specific substance that the receptor is meant to bind. This specificity helps to explain why human immunodeficiency virus (HIV) or any of the five types of hepatitis viruses invade only specific cells. |
Heterotrophic organisms use organic compounds, usually from other organisms, as a source of what basic element of life? | hydrogen | oxygen | monoxide | carbon | Heterotrophic organisms use organic compounds, usually from other organisms, as carbon sources. |
Electrons always result in what? | an dissociative that is larger than the parent atom | A HYPER-PIGMENTATION THAT IS LARGER THAN THE PARENT ATOM | an contraposition that is larger than the parent atom | an anion that is larger than the parent atom | The addition of electrons always results in an anion that is larger than the parent atom. When the electrons outnumber the protons, the overall attractive force that the protons have for the electrons is decreased. The electron cloud also spreads out because more electrons results in greater electron-electron repulsions. Notice that the group 16 ions are larger than the group 17 ions. The group 16 elements each add two electrons while the group 17 elements add one electron per atom for form the anions. |
The diffusion of water across a membrane because of a difference in concentration is called? | diffusion | absorption | hemostasis | osmosis | The diffusion of water across a membrane because of a difference in concentration is called osmosis . Let's explore three different situations and analyze the flow of water. |
Bioluminescence is an example of what type of activity that is carried out by a cell and is precisely coordinated and controlled? | reproduction | growth | respiration | metabolic | |
What reflex is commonly tested in newborn infants to establish the presence of neuromuscular function? | glandular | phalanges | renal | plantar | Approximate colors are shown, along with pKin values and the pH range over which the color changes. It is important to be aware that an indicator does not change color abruptly at a particular pH value; instead, it actually undergoes a pH titration just like any other acid or base. As the concentration of HIn decreases and the concentration of In− increases, the color of the solution slowly changes from the characteristic color of HIn to that of In−. As we will see in Section 16.6 "Buffers", the [In−]/[HIn] ratio changes from 0.1 at a pH one unit below pKin to 10 at a pH one unit above pKin. Thus most indicators change color over a pH range of about two pH units. We have stated that a good indicator should have a pKin value that is close to the expected pH at the equivalence point. For a strong acid–strong base titration, the choice of the indicator is not especially critical due to the very large change in pH that occurs around the equivalence point. In contrast, using the Saylor URL: http://www. saylor. org/books. |
All of the monatomic ions have oxidation numbers equal to their? | atomic weight | atomic number | shape | charges | There are 6 elements in this reaction. All of the monatomic ions have oxidation numbers equal to their charges. Additionally, we can assign an oxidation state of -2 to each oxygen atom and +1 to each hydrogen atom. Now, we just need to assign the oxidation states of manganese in MnO 4 - , nitrogen in the nitrite and nitrate ions, and sulfur in the sulfate ion. These can be determined by choosing a value for which all of the oxidation states in the ion add up to its overall charge. For example, in the nitrite ion:. |
Unlike plants, animal species rely almost exclusively on what type of reproduction? | regeneration | pollination | multiplication | sexual reproduction | Introduction Plants have evolved different reproductive strategies for the continuation of their species. Some plants reproduce sexually, and others asexually, in contrast to animal species, which rely almost exclusively on sexual reproduction. Plant sexual reproduction usually depends on pollinating agents, while asexual reproduction is independent of these agents. Flowers are often the showiest or most strongly scented part of plants. With their bright colors, fragrances, and interesting shapes and sizes, flowers attract insects, birds, and animals to serve their pollination needs. Other plants pollinate via wind or water; still others self-pollinate. |
Give an example of benthos that live near vents on the deep ocean floor. | arthropods | amphipods | crustaceans | tubeworms | Some benthos live near vents on the deep ocean floor. Tubeworms are an example ( Figure below ). Scalding hot water pours out of the vents. The hot water contains chemicals that some specialized bacteria can use to make food. Tubeworms have the bacteria living inside them. The bacteria get protection and the tubeworms get some of the food. |
What is the distinctive shape of the molecule that contains genetic information? | cylindrical | cube | conical | spiral | The spiral structure in the picture is a large organic molecule. Can you guess what it is? Here’s a hint: molecules like this one determine who you are. They contain genetic information that controls your characteristics. They determine your eye color, facial features, and other physical attributes. What molecule is it?. |
What is a bread mold and research organism that also grows in the wild on burned vegetation | whey | penicillin | nemophora | neurospora | |
How do most echinoderms reproduce? | grafting | asexually | flowering | sexually | Some echinoderms can reproduce asexually by fission, but most echinoderms reproduce sexually. They generally have separate sexes and external fertilization. Eggs hatch into free-swimming larvae. The larvae undergo metamorphosis to change into the adult form. During metamorphosis, their bilateral symmetry changes to radial symmetry. |
What do all cells have in common? | life span | same shape | same function | small size | Cells with different functions often vary in shape. They may also vary in size. However, all cells are very small. Even the largest organisms have microscopic cells. Cells are so small that their diameter is measured in micrometers. A micrometer is just one-millionth of a meter. Use the sliding scale at the following link to see how small cells and cell parts are compared with other objects. |
What do electric motors use to change electrical energy into kinetic? | fans | resonances | generators | electromagnets | Many common electric devices, such as doorbells, contain electromagnets. If they have moving parts, they are likely to have an electric motor. An electric motor is a device that uses an electromagnet to change electrical energy to kinetic energy. |
What are prokaryotic cells filled with? | protein | rna | chlorophyll | cytoplasm | cytoplasm. Like all other cells, prokaryotic cells are filled with cytoplasm. It includes watery cytosol and other structures. |
What is the name of plant-like protists? | bacteria | sponge | arthropod | algae | Plant-like protists are called algae (singular, alga). They are a large and diverse group. Some algae, diatoms, are single-celled. Others, such as seaweed, are multicellular (see Figure below ). |
A sticky, moist secretion that covers mucous membranes is called what? | saliva | sweat | pus | mucus | One way mucous membranes protect the body is by producing mucus. Mucus is a sticky, moist secretion that covers mucous membranes. The mucus traps pathogens and particles so they can’t enter the body. |
What system lets flatworms maintain a proper balance of water and salts? | digestive | homeostasis | nervous | excretory | Flatworms reflect several major evolutionary advances in invertebrates. They have three embryonic cell layers, including mesoderm. The mesoderm layer allows them to develop organ systems. For example, they have muscular and excretory systems. The muscular system allows them to move from place to place over solid surfaces. The excretory system lets them maintain a proper balance of water and salts. Flatworms also show cephalization and bilateral symmetry. |
What gas associated with global warming is released when limestone is heated during the production of cement? | oxygen | carbon monoxide | hydrogen | carbon dioxide | Carbon dioxide is released when limestone is heated during the production of cement. |
Because their embryos are surrounded by a thin membrane, reptiles are considered what? | lineages | carnivorous | vertebrates | amniotes | Reptiles are also amniotes, which means their embryos are surrounded by a thin membrane. |
What type of energy is clean and does not release greenhouse gases? | lithosphere energy | natural gas | coal | geothermal energy | Geothermal energy is clean and does not release greenhouse gases. |
Physical and chemical properties of geometric isomers are generally what? | similar | round | difficult | different | Physical and chemical properties of geometric isomers are generally different. While cis -2-butene is a polar molecule, trans -2-butene is nonpolar. Heat or irradiation with light can be used to bring about the conversion of one geometric isomer to another. The input of energy must be large enough to break the pi bond between the two carbon atoms, which is weaker than the sigma bond. At that point, the now single bond is free to rotate and the isomers can interconvert. |
What type of cell has a singular chromosome, no nucleus, and few other organelles? | monophyletic | trophic | graphic | prokaryotic | Cell division is simpler in prokaryotes than eukaryotes because prokaryotic cells themselves are simpler. Prokaryotic cells have a single circular chromosome, no nucleus, and few other organelles. Eukaryotic cells, in contrast, have multiple chromosomes contained within a nucleus and many other organelles. All of these cell parts must be duplicated and then separated when the cell divides. |
Protists, fungi, animals, and plants all consist of what kind of cells? | parenchyma | xylem | enzymes | eukaryotic | |
What does magma that cools underground form? | cracks | anomalies | plates | intrusions | Magma that cools underground forms intrusions ( Figure below ). Usually this magma is very viscous felsic magma. This magma does not rise easily and so cools slowly underground. Intrusions become land formations if they are exposed at the surface by uplift and erosion. |
What is used to report the results of scientific measurements? | los units | bi units | latin units | si units | The number in the measurement can be represented in different ways, including decimal form and scientific notation. (Scientific notation is also known as exponential notation; a review of this topic can be found in Appendix B. ) For example, the maximum takeoff weight of a Boeing 777-200ER airliner is 298,000 kilograms, which can also be written as 2.98 × 105 kg. The mass of the average mosquito is about 0.0000025 kilograms, which can be written as 2.5 × 10−6 kg. Units, such as liters, pounds, and centimeters, are standards of comparison for measurements. When we buy a 2-liter bottle of a soft drink, we expect that the volume of the drink was measured, so it is two times larger than the volume that everyone agrees to be 1 liter. The meat used to prepare a 0.25-pound hamburger is measured so it weighs onefourth as much as 1 pound. Without units, a number can be meaningless, confusing, or possibly life threatening. Suppose a doctor prescribes phenobarbital to control a patient’s seizures and states a dosage of “100” without specifying units. Not only will this be confusing to the medical professional giving the dose, but the consequences can be dire: 100 mg given three times per day can be effective as an anticonvulsant, but a single dose of 100 g is more than 10 times the lethal amount. We usually report the results of scientific measurements in SI units, an updated version of the metric system, using the units listed in Table 1.2. Other units can be derived from these base units. The standards for these units are fixed by international agreement, and they are called the International System of Units or SI Units (from the French, Le Système International d’Unités). SI units have been used by the United States National Institute of Standards and Technology (NIST) since 1964. Base Units of the SI System Property Measured. |
What is the first digestive organ that food enters? | esophagus | stomach | tongue | mouth | The mouth is the first digestive organ that food enters. The sight, smell, or taste of food stimulates the release of saliva and digestive enzymes by salivary glands inside the mouth. Saliva wets the food, which makes it easier to break up and swallow. The enzyme amylase in saliva begins the chemical digestion of starches to sugars. |
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