PHYSIO Homework 1

What would occur in the skin if the desmosomes stopped functioning? A. The skin would not show any wrinkles B. The skin would not be able to resist mechanical stress and break down easily C. The skin would become tougher and less likely to tear D. The skin would no longer be able to protect against bacterial infection

B. The skin would not be able to resist mechanical stress and break down easily

Which of the following results from the lipolysis of a triglyceride? A. Polysaccharides B. Glycerol and fatty acids C. Nucleic acids D. Amino acids

B. Glycerol and fatty acids

A series of reactions in the cytosol that split glucose A. Glucogen B. Glycolysis C. Glycogenesis D. Glycogenolysis E. Gluconeogenesis

B. Glycolysis

A substance that is oxidized_______________. A. Gains protons B. Loses electrons C. Loses protons D. Gains electrons

B. Loses electrons

Peristaltic contractions that propel the contents of the colon toward the distal large intestine are: A. Segmentation B. Mass movements C. Haustral contractions D. Defecation

B. Mass movements

Damage to the enteric nervous system that innervates the digestive organs could affect: A. Mastication B. Motility C. Salivation D. Daglutition

B. Motility

Is it possible for a molecules of hydrogen to form a hydrogen bond? A. No, since a molecules of hydrogen forms a polar covalent bond B. No, since a molecules of hydrogen forms a nonpolar covalent bond C. Yes, since a molecules of hydrogen forms a nonpolar covalent bond D. Yes, since a molecule of hydrogen forms a polar covalent bond

B. No, since a molecules of hydrogen forms a nonpolar covalent bond A molecule of hydrogen forms a nonpolar covalent bond where the electrons are shared equally and neither hydrogen has a partial charge. Hydrogen bonds only form between two molecules with partial charges.

A type of feedback that increases or enhances the effects of the variable is: A. Responsive B. Positive C. Negative D. Neutral

B. Positive

Which model would most accurately represent the current view of the structure of the atom? A. Planetary model B. Probability model

B. Probability model We cannot determine the exact motion of electrons. We can only compute the region where electrons occur most of the time. To emphasize the uncertainty, a diagram showing random motion is more suitable than planetary paths.

The cellular structure that can detect stimuli and send information to the control center is called the______________. A. Control center B. Receptor C. Effector D. Detector

B. Receptor Receptors are the first component of a feedback loop. They detect stimuli and send the information to a control center.

Which of the following does NOT increase surface area in the small intestine? A. Circular folds B. Rugae C. Microvilli D. Villi

B. Rugae

The alpha-helix and beta-pleated sheet are characteristic of: A. Primary protein structure B. Secondary protein structure C. Tertiary protein structure D. Quaternary protein structure

B. Secondary protein structure

Why would a disorder of the digestive system disrupt homeostasis? A. The digestive system plays a critical role in regulating volume, composition, and pH of body fluids by removing wastes to maintain homeostasis B. The digestive system plays a critical role in many physiological processes that contribute to the maintenance of homeostasis, including suppling dietary nutrients, absorbing water, minerals, and vitamins for health body tissues, and eliminating wastes C. The digestive system plays a critical role in delivering nutrients to body tissues and removing wastes in order to maintain homeostasis D. The digestive system plays a critical role in maintaining homeostasis by communication and regulation of body tissues via impulses and hormones

B. The digestive system plays a critical role in many physiological processes that contribute to the maintenance of homeostasis, including suppling dietary nutrients, absorbing water, minerals, and vitamins for health body tissues, and eliminating wastes The digestive system plays a role in many physiological processes that contribute to the maintenance of homeostasis, including regulation of fluid and electrolyte balance, acid-base balance, and nutrient balance. A disorder of the digestive system can, therefore, interfere with any of these processes.

Which statement best describes enzyme function? A. Enzymes speed chemical reactions by lowering the activation energy B. Enzymes can perform catabolic reactions only C. Enzymes chemically alter both the reactants and products D. One enzyme can work on thousands of different substances

A. Enzymes speed chemical reactions by lowering the activation energy

Which hormone promotes hunger? A. Ghrelin B. Leptin C. Gastrin D. Secretin

A. Ghrelin

Which of the following substances is not able to cross a plasma membrane via simple diffusion? A. Glucose B. Carbon dioxide C. Lipids D. Oxygen

A. Glucose

The process that stores excess glucose in skeletal muscle and hepatocytes A. Glycogenesis B. Glycolysis C. Glycogenolysis D. Gluconeogensis E. Glucogen

A. Glycogenesis

The process of breaking down glycogen into glucose molecules A. Glycogneolysis B. Glycogenesis C. Glucogen D. Gluconeogenesis E. Glycolysis

A. Glycogneolysis

What type of bond is responsible for the surface tension of water? A. Hydrogen bond B. Ionic bond C. Nonpolar covalent bond D. Polar covalent bond

A. Hydrogen bond

Paper cuts often involve only the epidermis. You may get a paper cut and notice that it doesn't bleed, but you can still feel it. Why can you feel it but the cut isn't bleeding? A. Merkel cells are found in the stratum basale and the cut is not extensive enough to reach the dermis. B. The dendritic cells are damaged; these are located in the stratum spinosum, but blood vessels are located deeper within the stratum basale. C. Merkel cells are scattered throughout the deeper layers of the dermis and are very sensitive to touch. D. There may be damage to the blood vessels, but it is too deep for us to see bleeding.

A. Merkel cells are found in the stratum basale and the cut is not extensive enough to reach the dermis.

Which of the following is NOT a nutrient monomer used by the body to generate ATP? A. Nucleic acids B. Amino acids C. Fatty acids D. Glucose

A. Nucleic acids

Why would a pharmacist recommend a patient with liver damage to be given a lower dose of medication over a longer period than what the doctor originally prescribed? A. Patients with liver disease metabolize drugs slower and they remain in the system longer than individuals with normal liver function B. Patients with liver disease store more carbohydrates and proteins which in turn reduces their ability to breakdown medications that are prescribed C. Patients with liver disease are incapable of metabolizing drugs in the liver so they take longer to metabolize the medications using the digestive functions of the pancreas and small intestines D. Patients with liver disease need lower doses of medications so they do not cause more damage to their liver cells while trying to metabolize them

A. Patients with liver disease metabolize drugs slower and they remain in the system longer than individuals with normal liver function

If a cell has 18 chromosomes and undergoes mitosis, how many chromosomes would each daughter cell have? A. 18 B. 72 C. 36 D. 9

A. 18

The mass number of an atom is 15, and its atomic number is 7. The atom probably has... A. 8 neutrons in the nucleus B. About as much mass in electrons as in protons C. At least 15 electrons D. 7 units of negative charge in the nucleus E. 7 electrons in the nucleus

A. 8 neutrons in the nucleus The atomic number (7) gives the number of protons, and the mass number is the number of protons plus neutrons.

A chemical system that resists changes in pH and prevents large swings in the pH is called_____________. A. A buffer B. An anion C. An acid D. A base

A. A buffer Typically, a buffer consists of a weak acid and its corresponding anion, and it can donate or accept free hydrogens

In the absence of oxygen, glucose is consumed extremely rapidly by the cell. However, glucose consumption decreases significantly when the cell is exposed to oxygen. What is the reasoning behind this? A. Absence of oxygen increases the amount of glycolysis reactions that occur to sustain ATP levels versus aerobic respiration. B. In the absence of oxygen, glycolysis speeds up its reactions that causes depletion of glucose. C. The presence of oxygen slows down Krebs cycle while absence of oxygen speeds up Krebs cycle. D. In the absence of oxygen glucose undergoes oxidative phosphorylation. This causes depletion of glucose reserve.

A. Absence of oxygen increases the amount of glycolysis reactions that occur to sustain ATP levels versus aerobic respiration.

Poisons that function by inhibiting a cell's enzyme could potentially be lethal because: A. Chemical reactions would proceed to slow to maintain life B. Chemical reactions would occur only periodically C. All chemical reactions in the cell will cease D. Chemical reactions would proceed too fast to maintain life

A. Chemical reactions would proceed to slow to maintain life Enzymes are biological molecules that help to increase the rate at which a reaction takes place by lowering the activation energy. Without enzymes, reactions in our cells would proceed at an extremely slow pace, too slow a pace to maintain life.

Many chemotherapy treatments for cancer kill rapidly dividing cells. What happens to a patient's digestive system on this kind of treatment? A. Chemotherapy treatments will reduce the ability of the mucosa to maintain its epithelial lining B. Chemotherapy treatments will reduce the ability of the serosa to maintain its epithelial lining C. Chemotherapy treatments will reduce the ability of the submucosa to maintain its epithelial lining D. Chemotherapy treatments will reduct the ability of the lamina propria to maintain its epithelial lining

A. Chemotherapy treatments will reduce the ability of the mucosa to maintain its epithelial lining The epithelium from the stomach to the end of the large intestine is simple columnar epithelium with copious mucus-secreting cells such as goblet cells. The mucus coats the epithelium, protecting it and the underlying tissues from ingested food and chemicals secreted by digestive organs. The mucosa also houses regenerative epithelial cells that have a high rate of mitosis. These cells allow the mucosa to replace epithelial cells as they are damaged or sloughed off in the alimentary canal. Chemotherapy drugs that cause the death of the rapidly dividing cells will kill many of these cells, reducing the ability of the mucosa of the alimentary canal to maintain its epithelial lining.

Mary's stroke left her unable to swallow. What specialized type of propulsion was affected? A. Deglutition B. Mastication C. Segmentation D. Salivation

A. Deglutition

Which of the following is NOT one of the three major components of animal cells? A. ECF B. Nucleus C. Plasma membrane D. Cytoplasm

A. ECF The ECF, or extracellular fluid, is the fluid that fills the space outside cells, so it is not a component of cells.

Sodium ions are moving with their concentration gradient with the use of a protein channel across a plasma membrane. Determine the type of membrane transport used to transport these sodium ions. A. Facilitated diffusion B. Primary active transport C. Osmosis D. Simple diffusion

A. Facilitated diffusion

Which of the following membrane transport mechanisms requires ATP? A. Primary active transport B. Facilitated diffusion C. Simple diffusion D. Osmosis

A. Primary active transport During primary active transport, a protein "pumps" a solute against its concentration gradient using energy from ATP.

Which of the following is NOT a process occurring in the oral cavity? A. Segmentation B. Chemical digestion C. Ingestion D. Propulsion

A. Segmentation

The transfer of a phosphate group from creatine phosphate to ADP is classified as: A. Substrate-level phosphorylation B. First phosphorylation C. Second phosphorylation D. Oxidative phosphorylation

A. Substrate-level phosphorylation

The total amount of energy expended by the body to power all of its processes is called: A. The metabolic rate B. The basal metabolic rate C. Homeostasis D. Cellular respiration

A. The metabolic rate

Why does the amount of carbon dioxide exhaled increase when exercising? A. The muscles utilize the ATP at greater amounts, and they need to undergo aerobic respiration to synthesize more ATP. B. Oxidative phosphorylation produces more carbon dioxide as oxygen is being used up in the reactions. C. Increase in glycolysis produces more carbon dioxide. D. Carbon dioxide is used in beta oxidation to produce ATP

A. The muscles utilize the ATP at greater amounts, and they need to undergo aerobic respiration to synthesize more ATP. More muscle activity equates to increase metabolism of glucose to produce ATP. The conversion of pyruvate into acetyl coA and citric acid cycle produces carbon dioxide as byproduct.

Two atoms always represent the same element if they have... A. The same number of protons B. The same number of shells C. The sam mass number D. The same number of electrons E. The same number of particles in the nucleus

A. The same number of protons The number of protons defines a chemical element. The number of neutrons and electrons can differ among atoms of the same element.

The role of tRNA in translation is___________. A. To bring amino acids to the ribosome B. To encode the sequence of amino acids C. To hold the mRNA transcript in place D. To form the peptide bone between amino acids

A. To bring amino acids to the ribosome tRNA is called "transfer" RNA because its job is to pick up a specific amino acid from the cytosol and transfer it to the growing polypeptide chain at the ribosome.

What liver secretion is responsible for the emulsification of lipids in the duodenum? A. bile B. Pancreatic juice C. secretin D. cholecystokinin (CCK)

A. bile

The removal of the gallbladder will affect: A. bile storage B. bile production C. motility of the stomach D. carbohydrate digestion

A. bile storage

Which pH represents a solution that has the highest concentration of hydroxide ions? A. pH 14 B. pH 7 C. pH 1 D. pH 10

A. pH 14

If NADH and FADH2 fail to be oxidized as part of the electron transport chain (ETC), what is affected? A. the electromotive force required to drive the electron transport chain (ETC) B. the regeneration of oxaloacetate C. the phosphorylation and oxidation of glyceraldehyde-3-phosphate D. the formation of acetyl-CoA

A. the electromotive force required to drive the electron transport chain (ETC)

In which process of cellular respiration is water produced? A.Electron transport chain B. Glycolysis C. Citric acid cycle D. Citrate synthesis

A.Electron transport chain

An atom has 8 protons, 8 neutrons, and 8 electrons. Another isotope of the same element might have... A. 9 protons B. 10 neutrons C. Mass number 16, atomic number 7 D. 7 electrons E. All of the above

B. 10 neutrons Isotopes have the same number of protons different number of neutrons.

Which of the following reactions is driven by glucose catabolism? A. ATP catabolism B. ATP synthesis C. ATP oxidation-reduction D. ATP hydrolysis

B. ATP synthesis

ATP hydrolysis would yield all of the following, EXCEPT___________. A. ADP B. Adenosine C. Phosphate group D. Energy

B. Adenosine Adenosine is a component of ATP, but ATP hydrolysis only removes a phosphate, so the resulting molecule is an adenosine with two phosphates still attached to it.

Radioactive decay is likely to occur when... A. An atom has too many electrons B. An atom has too many neutrons C. Protons break into neutrons and electrons D. An electron hits the nucleus E. Atoms collide with one another

B. An atom has too many neutrons The atomic nucleus becomes unstable if the ratio of protons to neutrons is too far from unity.

Why is cholesterol a critical component of the plasma membrane? A. Cholesterol serves a role in cell recognition B. Cholesterol stabilizes the structure of the plasma membrane when the temperature changes C. Cholesterol catalyzes metabolic reactions from its position within the plasma membrane D. Cholesterol transport certain molecules into the cell

B. Cholesterol stabilizes the structure of the plasma membrane when the temperature changes

Which of the following characteristics is NOT one of the unique characteristics of living organisms? A. Reproduction B. Composed of atoms c. Metabolism D. Responsiveness

B. Composed of atoms

While woodworking, your friend Lily cuts her forearm with a saw. You examine the wound and see large quantities of adipose tissue at its base. Her wound extends down to the ____. A. hyperdermis B. Deeper than the cutaneous membrane C. Dermis D. Epidermis

B. Deeper than the cutaneous membrane

What type of reaction releases energy? A. Endergonic reaction B. Exergonic reaction C. Catabolic reaction D. Equilibrium reaction

B. Exergonic reaction

Oleander (Nerium oleander) is a common but poisonous ornamental shrub. All parts of the plant contain chemicals that inhbit the Na+/K+ pump. How would this affect sodium-glucose symporters (secondary active transport) of a given cell? A. K+ would increase in higher concentration inside the cell B. Glucose levels within the cell would decrease C. Sodium would enter the cell at a higher rate D. Glucose would increasingly diffuse into the cell

B. Glucose levels within the cell would decrease The secondary active transport allows glucose to enter the cell. Although the poison would affect the pump, this would indirectly impact the transport of glucose into the cell because sodium is needed for glucose to enter.

Elastic connective tissue is found in large blood vessels of the body. What would occur in these vessels if the elastic fibers were replaced with collagen fibers? A. The vessels would increase in size and rupture, causing an aneurysm B. The vessels would lose their ability to stretch and become tough C. The vessels would not be able to resist pressure D. The vessels would not be able to resist tension

B. The vessels would lose their ability to stretch and become tough

How are pathways of protein, lipid, and carbohydrate catabolism similar? A. All three pathways undergo transamination B. They all can ultimately undergo citric acid cycle C. All three pathways can undergo β-oxidation D. They all undergo glycolysis

B. They all can ultimately undergo citric acid cycle All three pathways can produce acetyl coA to enter Krebs cycle and reduce electron carriers.

Ricin inhibits the functioning of ribosomes. What part of protein synthesis would be affected by ricin? What effect would this have on a cell's ability to synthesize proteins? A. Post-transcriptional modification would be inhibited B. Translation process would be inhibited C. Protein modification would be inhibited D. Transcription would be inhibited

B. Translation process would be inhibited Ribosome are involved in translation and therefore will be effected.

Which of the following is NOT a function of the skin? A. Protection B. Vitamin A synthesis C. Thermoregulation D. Sensation

B. Vitamin A synthesis

Which of the following vitamins is absorbed in the ileum after binding to intrinsic factor? A. Vitamin C B. Vitamin B12 C. Vitamin D D. Vitamin B6

B. Vitamin B12

Which statement is true of the energy levels of electrons in shells? A. Electrons must lose energy to move from the first to the second shell B. the valence shell has higher energy than other occupied shells C. All the electrons in an atom have similar amounts of energy D. All of the above E. None of the above

B. the valence shell has higher energy than other occupied shells The outer occupied shell is the valence shell, and outer shells hold electrons at higher energy than inner shells.

How many homologous chromosome pairs are present in most human cells? A. 4 B. 46 C. 23 D. 18

C. 23

An element of lithium has an atomic number of 3 and a mass number of 7. Lithium must have: A. 3 protons, 4 electrons and 3 neutrons B. 4 protons, 3 electrons and 3 neutrons C. 3 protons, 3 electrons and 4 neutrons D. 4 protons, 4 electrons and 4 neutrons

C. 3 protons, 3 electrons and 4 neutrons

A drug inhibits the work of ATP synthase. Determine the effect on chemiosmosis. A. Carbon dioxide would no long be made as a result of ATP production B. ATP production would increase rapidly C. ATP production would stop D. Oxygen would no longer be required for ATP production

C. ATP production would stop

What type of organic molecule must undergo transamination prior to being used for ATP synthesis? A. Glucose B. Fatty acids C. Amino acids D. Glycerol

C. Amino acids

The stage of mitosis during which sister chromatids separate and daughter chromosomes are pulled to opposite poles of the cell is called_____________. A. Metaphase B. Prophase C. Anaphase D. Telophase

C. Anaphase Sister chromatids separate and daughter chromosomes are pulled to opposite poles of the cell during the third stage of mitosis, called anaphase.

Type 1 diabetes mellitus results from inability to produce the hormone insulin. How would this condition change the normal events of absorptive state? A. Most body cells will increase uptake of glucose B. Amino acid anabolism will increase C. Body will catabolize lipids D. Ketone production would decrease

C. Body will catabolize lipids Because blood sugar levels are high and not getting absorbed into body cells, they have to rely on fatty acid and amino acid catabolism Return to Assignment

The storage form of glucose A. Gluconeogenesis B. Glycogenolysis C. Glucogen D. Glycogenesis E. Glycolysis

C. Glucogen

What type of compound is NOT likely to dissolve in water? A. Ionic compound B. Polar covalent compound C. Nonpolar covalent compound D. Both polar and nonpolar covalent compounds

C. Nonpolar covalent compound The attractive forces that operate between the particles in a nonpolar compound are weak dispersion forces. However, the nonpolar molecules are more attracted to themselves than they are to the polar water molecules.

Since her stomach was removed, Mrs. Lopez has the most difficulty initiating digestion of: A. Monosaccharides B. Oligosaccharides C. Proteins D. Lipids

C. Proteins

In glycolysis, glucose is split into two_______________. A. Citrates B. Acetyl-CoAs C. Pyruvate's D. ATPs

C. Pyruvate's

What digestive functions would be affected by the removal of the pancreas from a patient with pancreatic cancer? A. Removal of the pancreas will severely impact the detoxification of substances produced by the body and those that we eat and drink that can be harmful to the body. B. Removal of the pancreas would not allow the duodenum to secrete the hormones secretin and CCK into the blood to digest lipids and proteins. C. Removal of the pancreas would severely impact chemical digestion because the pancreatic juices contain multiple digestive enzymes needed to digest all types of nutrients. D. Removal of the pancreas will eliminate the release of bile from the pancreas and hinder the digestion and absorption of lipids and excretion of wastes that the kidney cannot excrete.

C. Removal of the pancreas would severely impact chemical digestion because the pancreatic juices contain multiple digestive enzymes needed to digest all types of nutrients. The collective secretions of the pancreatic acinar and duct cells are known as pancreatic juice. It consists of water and multiple digestive enzymes and other proteins. In addition, the duct cells secrete bicarbonate ions, a base, which makes pancreatic juice alkaline. This helps to neutralize the acidic chyme that enters the duodenum from the stomach and protects the duodenum from damage by the acid. The digestive enzymes, secreted by acinar cells, are crucial in chemical digestion and catalyze the reactions that digest carbohydrates, proteins, lipids, and nucleic acids.

Dr. Jones says an atom has 3 electrons in the first shell and four electrons in the second shell. Someone should tell Dr. Jones that... A. The second shell can't have 4 electrons B. The first shell must fill before the second shell can have electrons C. The first shell shouldn't have 3 electrons D. No shell can hold more than 2 electrons E. The second shell should have 8 electrons

C. The first shell shouldn't have 3 electrons The first shell can only have 0, 1, or 2 electrons.

Predict what will happen to a person's red blood cells if he or she were given the following fluids together intravenously: 300mL of normal saline (isotonic) solution mixed with 300mL of 10% dextrose solution (hypertonic solution). A. The red blood cells would not change in size B. The red blood cells would burst C. The red blood cells would crenate D. The red blood cells would increase in size

C. The red blood cells would crenate Because this is a mixture of equal parts isotonic and hypertonic solutions, the overall solution will be on average, hypertonic. Water will follow whichever way solutes are greater, so the red blood cells would lose water to their extracellular environment.

The sum of all biochemical reactions that take place in the human body at any given time is called_____________. A. phosphorylation B. anabolism C. metabolism D. catabolism

C. metabolism Metabolic reactions are divided into two main types: anabolic and catabolic.

If the intercalated discs of cardiac muscle lost their functionality... A. the heart muscle would contract at random sometimes and in unison at other times. B. the heart muscle would contract in unison. C. the heart muscle would not be able to contract in unison. D. the heart muscle would increase blood volume in the vessels.

C. the heart muscle would not be able to contract in unison.

The homeostatic mechanism, in which a stimulus changes the regulated variable in one direction but the response changes the variable in the opposite direction, is called a _______________. A. Dynamic equilibrium B. Cell-cell communication C. A positive feedback loop D. A negative feedback loop

D. A negative feedback loop In a negative feedback loop the effector activity opposes the initial stimulus and shuts off when the conditions return to the normal range.

Yuri is working with a chemical in lab. This chemical is composed of repetitive units that include a phosphate group, and nitrogenous base, and a sugar known as ribose. He is working with: A. A carbohydrate B. A protein C. A lipid D. A nucleic acid

D. A nucleic acid

Which is not an endocrine hormone secreted by the pancreas? A. Somatostatin B. Glucagon C. Insulin D. Aldosterone

D. Aldosterone Aldosterone is a hormone secreted by the adrenal cortex, not the pancreas.

Which statement is true of the atom shown in the diagram? A. The atom is in the excited state B. An electron will move from the outer to the inner shell C. The atom has more than one valence electron D. All of the above E. None of the above

D. All of the above The atom has a vacancy in its inner shell; an electron has moved to the outer (valence) shell. The result is an unstable excited state. An electron will move back to the inner shell, restoring the ground state as the atom gives off energy.

The conversion of pepsinogen into the active form, pepsin, requires: A. Intrinsic factor B. Vitamin B12 C. Alkaline mucus D. An acidic pH

D. An acidic pH

Essential nutrients: A. Are made by the body B. Include most carbohydrates C. Include cholesterol D. Are only obtained through diet

D. Are only obtained through diet

At atom has 6 electrons, 6 protons, and 6 neutrons. You can that this atom belongs to the element______because______________. A. O; its mass number is 12 B. N; it has 6 protons C. N; it has 6 electrons D. C; it has 6 protons E. C; it has 6 electrons

D. C; it has 6 protons Atoms represent the element carbon (C) if they have 6 protons.

Which of the following is an appropriate skin response to cold? A. Sebaceous gland secretions increase B. Vitamin D production increases C. Dermal blood vessels vasodilate D. Dermal blood vessels vasoconstrict

D. Dermal blood vessels vasoconstrict

A scar located in the tarsal region of the left leg would be considered_______________ to the patellar region. A. Superior B. Anterior C. Superficial D. Distal

D. Distal

Which statement is true of atoms? A. Most of an atom's volume is filled with matter B. Protons repel electrons C. Protons attract other protons D. Electrons determine the atom's size E. All of the above

D. Electrons determine the atom's size With electrons on the surface, atoms repel one another when they come too close. Thus, electrons determine the space that an atom occupies.

Which biological catalyst lower the activation energy of a reaction? A. Carbohydrate B. Lipid C. Salt D. Enzyme

D. Enzyme

What would happen to a cell if a mutation resulted in the formation of insufficient oxaloacetate in the citric acid cycle? A. There would be an increase in number of electron carriers produced B. There would be a decrease in NAD+ production C. The levels of malate would accumulate D. Fewer electron carriers would be produced

D. Fewer electron carriers would be produced

The products of glycogenolysis are the same as the products of: A. Glycogenesis B. Glycolysis C. Lipolysis D. Gluconeogenesis

D. Gluconeogenesis

Vitiligo is a condition characterized by death or dysfunction of scattered groups of melanocytes in the skin. How might vitiligo cause the skin to appear? A. It causes a lighter skin tone B. It may cause the skin to appear yellow-orange C. It causes a pinkish hue D. It may cause dark patches along with lighter patches

D. It may cause dark patches along with lighter patches

Mr. Alcozer comes into a clinic for a follow-up appointment after having been diagnosed with high cholesterol. The nurse notes that his total cholesterol has decreased from 250 mg/dl to 230 mg/dl, his LDL cholesterol has remained the same at 200 mg/dl, and his HDL cholesterol has decreased from 50 mg/dl to 20 mg/dl. Do these numbers represent an overall improvement in his condition? A. Mr. Alcozer improved in his overall condition because his HDL levels have dropped and because total cholesterol decreased. B. Mr. Alcozer improved in his overall condition because his HDL levels have dropped C. Mr. Alcozer improved in his overall condition because his total cholesterol decreased. D. Mr. Alcozer's overall condition got worse because his HDL levels dropped while LDL levels stayed the same.

D. Mr. Alcozer's overall condition got worse because his HDL levels dropped while LDL levels stayed the same.

Why do diets with extremely low in carbohydrates often cause people to experience mental "fogginess" and decreased mental stamina? A. Low carbohydrate diet increases glycogenesis B. Decrease in ketone bodies can cause blood pH to decrease and affect mental state. C. β-oxidation synthesizes amino acids that may decrease mental functioning. D. Neurons rely on glucose for ATP

D. Neurons rely on glucose for ATP Glucose catabolism is the optimal way for neurons to obtain energy. If levels of carbohydrates are low through diet, glucose levels will drop.

If body temperature increased above its normal range but was regulated by a positive feedback loop, what would likely occur? A. Decreased core body temperature B. Increased temperature in upper limbs only C. The decreased temperature in the torso only D. None of the answers are correct

D. None of the answers are correct The temperatures in the body would keep increasing.

Proton-pump inhibitors are drugs that block the secretions of gastric acids. Which cells are affected by these drugs? A. Diffuse neuroendocrine system (DNES) cells B. Chief cells C. Mucous neck cells D. Parietal cells

D. Parietal cells

Heat is exchanged between the body and the environment by all of the following mechanisms EXCEPT: A. Evaporation B. Convection C. Radiation D. Precipitation

D. Precipitation

Chemists assign atoms to chemical elements by counting their__________________. A. Isotopes B. Electrons C. Neutrons D. Protons

D. Protons Elements are defined by the number of protons. Protons give an enduring basis for atomic behaviors because they are permanently anchoring in the nucleus, where their attraction determines how many electrons the atom can hold. By contract, electrons come and go, and the numbers vary. Isotopes of the same element vary in the number of neutrons in the nucleus of the atom.

Blood is a mixture of fluid and insoluble particles that are large enough to be visible, such as blood cells and platelets. Therefore, blood is a____________. A. Solution B. Solvent C. Colloid D. Suspension

D. Suspension Blood is an example of a suspension. Blood cells are "suspended" in the plasma, the fluid portion of blood.

Cytokinesis occurs concurrently with what stage of mitosis? A. Prophase B. Metaphase C. Interphase D. Telophase

D. Telophase Cytokinesis, which dives the cytosol and organelles equally between the two daughter cells, occurs at the same time as telophase.

What would happen if a cell completed several round of mitosis but did not undergo cytokinesis? A. The cell would stay in G0 phase until it completes cytokinesis B. It would not reach G1 phase C. The cell would undergo DNA replication D. The cell would keep getting larger in size

D. The cell would keep getting larger in size Cytokinesis is the fundamental process needed to split the cell into two cells. If this does not occur, the size of the cell would increase in size.

Intestines have many folds on their surface, and this increase in surface area makes absorption of nutrients faster and more efficient. This is an example of_______________. A. A negative feedback loop B. Cell-cell communication C. A structural gradient D. The principle of complementarity of structure and function

D. The principle of complementarity of structure and function The structure of the intestines is such that they are better suited for their function - nutrient absorption.

The unit of DNA that specifies a certain amino acid is called a_____________, the same unit of mRNA is called a(n)_________________ which, during protein synthesis, is matched by the____________of tRNA. A. Nucleotide; triplet; gene B. Gene; triplet; amino acid C. Triplet; anticodon; codon D. Triplet; codon; anticodon

D. Triplet; codon; anticodon

The synthesis of glucose from noncarbohydrate molecules such as glycerol or certain amino acids A. Glycolysis B. Glycogenesis C. Glucogen D. Glycogenolysis E. Gluconeogenesis

E. Gluconeogenesis