A&P TESTTT 1

15. The nucleus and mitochondria share which of the following features?

. a double cell membrane

25. C6 H12 O6 is the chemical formula for a ________.

. hexose monosaccharide

14. Humans have the most urgent need for a continuous supply of ________.

. oxygen

6. The characteristic that gives an element its distinctive properties is its number of ________.

. protons

16. Which of the following structures could be found within the nucleolus?

. ribosomes

36. Explain why CH4 is one of the most common molecules found in nature. Are the bonds between the atoms ionic or covalent?

A carbon atom has four electrons in its valence shell. According to the octet rule, it will readily participate in chemical reactions that result in its valence shell having eight electrons. Hydrogen, with one electron, will complete its valence shell with two. Electron sharing between an atom of carbon and four atoms of hydrogen meets the requirements of all atoms. The bonds are covalent because the electrons are shared: although hydrogen often participates in ionic bonds, carbon does not because it is highly unlikely to donate or accept four electrons.

15. Which of the following statements about nutrients is true?

All classes of nutrients are essential to human survival.

28. Name at least three reasons to study anatomy and physiology.

An understanding of anatomy and physiology is essential for any career in the health professions. It can also help you make choices that promote your health, respond appropriately to signs of illness, make sense of health-related news, and help you in your roles as a parent, spouse, partner, friend, colleague, and caregiver.

17. Which of the following sequences on a DNA molecule would be complementary to GCTTATAT?

CGAATATA

17. ________ reactions release energy.

Catabolic, exergonic, and decomposition

30. Name the six levels of organization of the human body

Chemical, cellular, tissue, organ, organ system, organism.

13. Which of the following statements about chemical bonds is true?

Covalent bonds are stronger than ionic bonds.

20. Which of the following is not a difference between DNA and RNA?

DNA contains alternating sugar-phosphate molecules whereas RNA does not contain sugars

35. Explain in your own words why DNA replication is said to be "semiconservative"?

DNA replication is said to be semiconservative because, after replication is complete, one of the two parent DNA strands makes up half of each new DNA molecule. The other half is a newly synthesized strand. Therefore, half ("semi") of each daughter DNA molecule is from the parent molecule and half is a new molecule.

42. During a party

Eli loses a bet and is forced to drink a bottle of lemon juice. Not long thereafter, he begins complaining of having difficulty breathing, and his friends take him to the local emergency room. There, he is given an intravenous solution of bicarbonate. Why?, Lemon juice, like any acid, releases hydrogen ions in solution. As excessive H+ enters the digestive tract and is absorbed into blood, Eli's blood pH falls below 7.35. Recall that bicarbonate is a buffer, a weak base that accepts hydrogen ions. By administering bicarbonate intravenously, the emergency department physician helps raise Eli's blood pH back toward neutral.

42. Discuss two reasons why the therapeutic use of embryonic stem cells can present a problem.

Embryonic stem cells derive from human embryos, which are destroyed to obtain the cells. The destruction of human embryos is an ethical problem. And, the DNA in an embryonic stem cell would differ from the DNA of the person being treated, which could result in immune problems or rejected of tissue.

View this animation (http://openstaxcollege.org/l/metabolic) to learn more about metabolic processes. What kind of catabolism occurs in the heart?

Fatty acid catabolism.

24. Which of the following phases is characterized by preparation for DNA synthesis?

G1

33. Identify three different ways that growth can occur in the human body.

Growth can occur by increasing the number of existing cells, increasing the size of existing cells, or increasing the amount of non-cellular material around cells.

38. Could two atoms of oxygen engage in ionic bonding? Why or why not?

Identical atoms have identical electronegativity and cannot form ionic bonds. Oxygen, for example, has six electrons in its valence shell. Neither donating nor accepting the valence shell electrons of the other will result in the oxygen atoms completing their valence shells. Two atoms of the same element always form covalent bonds.

39. AB + CD → AD + BE Is this a legitimate example of an exchange reaction? Why or why not?

It is not. An exchange reaction might be AB + CD → AC + BD or AB + CD → AD + BC. In all chemical reactions, including exchange reactions, the components of the reactants are identical to the components of the products. A component present among the reactants cannot disappear, nor can a component not present in the reactants suddenly appear in the products.

35. On his midsummer trek through the desert

Josh ran out of water. Why is this particularly dangerous?,The primary way that the body responds to high environmental heat is by sweating; however, sweating requires water, which comes from body fluids, including blood plasma. If Josh becomes dehydrated, he will be unable to sweat adequately to cool his body, and he will be at risk for heat stroke as his blood pressure drops too much from the loss of water from the blood plasma.

20. What is the position of the body when it is in the "normal anatomical position?"

None of the above

39. What would happen if anaphase proceeded even though the sister chromatids were not properly attached to their respective microtubules and lined up at the metaphase plate?

One or both of the new daughter cells would accidently receive duplicate chromosomes and/or would be missing certain chromosomes.

25. Which of the following imaging techniques would be best to use to study the uptake of nutrients by rapidly multiplying cancer cells?

PET

5. PET relies on radioactive substances administered several minutes before the scan. Watch this video (http://openstaxcollege.org/l/PET) to learn more about PET. How is PET used in chemotherapy?

PET scans can indicate how patients are responding to chemotherapy

34. Compare and contrast lysosomes with peroxisomes: name at least two similarities and one difference.

Peroxisomes and lysosomes are both cellular organelles bound by lipid bilayer membranes, and they both contain many enzymes. However, peroxisomes contain enzymes that detoxify substances by transferring hydrogen atoms and producing H2O2, whereas the enzymes in lysosomes function to break down and digest various unwanted materials.

31. Why is receptor-mediated endocytosis said to be more selective than phagocytosis or pinocytosis?

Receptor-mediated endocytosis is more selective because the substances that are brought into the cell are the specific ligands that could bind to the receptors being endocytosed. Phagocytosis or pinocytosis, on the other hand, have no such receptor-ligand specificity, and bring in whatever materials happen to be close to the membrane when it is enveloped.

31. The female ovaries and the male testes are a part of which body system? Can these organs be members of more than one organ system? Why or why not?

The female ovaries and the male testes are parts of the reproductive system. But they also secrete hormones, as does the endocrine system, therefore ovaries and testes function within both the endocrine and reproductive systems.

36. Identify the four components of a negative feedback loop and explain what would happen if secretion of a body chemical controlled by a negative feedback system became too great.

The four components of a negative feedback loop are: stimulus, sensor, control center, and effector. If too great a quantity of the chemical were excreted, sensors would activate a control center, which would in turn activate an effector. In this case, the effector (the secreting cells) would be adjusted downward.

2. Water concentration in the body is critical for proper functioning. A person's body retains very tight control on water levels without conscious control by the person. Watch this video (http://openstaxcollege.org/l/H2Ocon) to learn more about water concentration in the body. Which organ has primary control over the amount of water in the body?

The kidneys.

4. A patient undergoing an MRI is surrounded by a tube-shaped scanner. Watch this video (http://openstaxcollege.org/l/MRI) to learn more about MRIs. What is the function of magnets in an MRI?

The magnets induce tissue to emit radio signals that can show differences between different types of tissue.

3. Watch this video (http://openstaxcollege.org/l/disaccharide) to observe the formation of a disaccharide. What happens when water encounters a glycosidic bond?

The water hydrolyses, or breaks, the glycosidic bond, forming two monosaccharides.

13. Which of the following is a feature common to all three components of the cytoskeleton?

They are all polymers of protein subunits.

4. Watch this video (http://openstaxcollege.org/l/ribosome) to learn about ribosomes. The ribosome binds to the mRNA molecule to start translation of its code into a protein. What happens to the small and large ribosomal subunits at the end of translation?

They separate and move and are free to join translation of other segments of mRNA.

37. Briefly explain the similarities between transcription and DNA replication.

Transcription and DNA replication both involve the synthesis of nucleic acids. These processes share many common features—particularly, the similar processes of initiation, elongation, and termination. In both cases the DNA molecule must be untwisted and separated, and the coding (i.e., sense) strand will be used as a template. Also, polymerases serve to add nucleotides to the growing DNA or mRNA strand. Both processes are signaled to terminate when completed.

41. Explain how a transcription factor ultimately determines whether or not a protein will be present in a given cell?

Transcription factors bind to DNA and either promote or inhibit the transcription of a gene. If they promote the transcription of a particular gene, then that gene will be transcribed and the mRNA subsequently translated into protein. If gene transcription is inhibited, then there will be no way of synthesizing the gene's corresponding protein.

38. Contrast transcription and translation. Name at least three differences between the two processes.

Transcription is really a "copy" process and translation is really an "interpretation" process, because transcription involves copying the DNA message into a very similar RNA message whereas translation involves converting the RNA message into the very different amino acid message. The two processes also differ in their location: transcription occurs in the nucleus and translation in the cytoplasm. The mechanisms by which the two processes are performed are also completely different: transcription utilizes polymerase enzymes to build mRNA whereas translation utilizes different kinds of RNA to build protein.

24. Ty is three years old and as a result of a "stomach bug" has been vomiting for about 24 hours. His blood pH is 7.48. What does this mean?

Ty's blood is slightly alkaline.

41. Explain why ultrasound imaging is the technique of choice for studying fetal growth and development.

Ultrasonography does not expose a mother or fetus to radiation, to radiopharmaceuticals, or to magnetic fields. At this time, there are no known medical risks of ultrasonography.

24. In 1901

Wilhelm Röntgen was the first person to win the Nobel Prize for physics. For what discovery did he win?,. X-rays

3. A CT or CAT scan relies on a circling scanner that revolves around the patient's body. Watch this video (http://openstaxcollege.org/l/CATscan) to learn more about CT and CAT scans. What type of radiation does a CT scanner use?

X-rays.

29. For whom would an appreciation of the structural characteristics of the human heart come more easily: an alien who lands on Earth

abducts a human, and dissects his heart, or an anatomy and physiology student performing a dissection of the heart on her very first day of class? Why?, A student would more readily appreciate the structures revealed in the dissection. Even though the student has not yet studied the workings of the heart and blood vessels in her class, she has experienced her heart beating every moment of her life, has probably felt her pulse, and likely has at least a basic understanding of the role of the heart in pumping blood throughout her body. This understanding of the heart's function (physiology) would support her study of the heart's form (anatomy).

8. Ion pumps and phagocytosis are both examples of ________.

active transport

31. Uracil ________.

all of the above (contains nitrogen, is a pyrimidine, is found in RNA)

27. Which of the following is a functional group that is part of a building block of proteins?

amino

3. Watch this video (http://openstaxcollege.org/l/DNArep) to learn about DNA replication. DNA replication proceeds simultaneously at several sites on the same molecule. What separates the base pair at the start of DNA replication?

an enzyme

40. What are cyclins and cyclin-dependent kinases

and how do they interact?, A cyclin is one of the primary classes of cell cycle control molecules, while a cyclin-dependent kinase (is one of a group of molecules that work together with cyclins to determine progression past cell checkpoints. By interacting with many additional molecules, these triggers push the cell cycle forward unless prevented from doing so by "stop" signals, if for some reason the cell is not ready.

38. In which direction would an MRI scanner move to produce sequential images of the body in the frontal plane

and in which direction would an MRI scanner move to produce sequential images of the body in the sagittal plane?, If the body were supine or prone, the MRI scanner would move from top to bottom to produce frontal sections, which would divide the body into anterior and posterior portions, as in "cutting" a deck of cards. Again, if the body were supine or prone, to produce sagittal sections, the scanner would move from left to right or from right to left to divide the body lengthwise into left and right portions.

41. The pH of lemon juice is 2

and the pH of orange juice is 4. Which of these is more acidic, and by how much? What does this mean?, Lemon juice is one hundred times more acidic than orange juice. This means that lemon juice has a one hundred-fold greater concentration of hydrogen ions.

40. Which medical imaging technique is most dangerous to use repeatedly

and why?, CT scanning subjects patients to much higher levels of radiation than X-rays, and should not be performed repeatedly.

Visit this link (http://openstaxcollege.org/l/diffusion) to see diffusion and how it is propelled by the kinetic energy of molecules in solution. How does temperature affect diffusion rate

and why?, Higher temperatures speed up diffusion because molecules have more kinetic energy at higher temperatures.

30. What materials can easily diffuse through the lipid bilayer

and why?, Only materials that are relatively small and nonpolar can easily diffuse through the lipid bilayer. Large particles cannot fit in between the individual phospholipids that are packed together, and polar molecules are repelled by the hydrophobic/nonpolar lipids that line the inside of the bilayer.

2. Visit this website (http://openstaxcollege.org/l/electenergy) to learn about electrical energy and the attraction/repulsion of charges. What happens to the charged electroscope when a conductor is moved between its plastic sheets

and why?, The plastic sheets jump to the nail (the conductor), because the conductor takes on electrons from the electroscope, reducing the repellant force of the two sheets.

25. A mutation in the gene for a cyclin protein might result in which of the following?

any of the above (a cell with additional genetic material than normal, cancer, a cell with less genetic material than normal)

5. The smallest unit of an element that still retains the distinctive behavior of that element is an ________.

atom

19. Which of the following is part of the elongation step of DNA synthesis?

attaching complementary nucleotides to the template strand

16. C.J. is stuck in her car during a bitterly cold blizzard. Her body responds to the cold by ________.

breaking down stored energy

9. Which of the following is a molecule

but not a compound?,. H2

32. Explain why the smell of smoke when you are sitting at a campfire does not trigger alarm

but the smell of smoke in your residence hall does., When you are sitting at a campfire, your sense of smell adapts to the smell of smoke. Only if that smell were to suddenly and dramatically intensify would you be likely to notice and respond. In contrast, the smell of even a trace of smoke would be new and highly unusual in your residence hall, and would be perceived as danger.

33. The most abundant elements in the foods and beverages you consume are oxygen

carbon, hydrogen, and nitrogen. Why might having these elements in consumables be useful?, These four elements—oxygen, carbon, hydrogen, and nitrogen—together make up more than 95 percent of the mass of the human body, and the body cannot make elements, so it is helpful to have them in consumables.

8. The smallest independently functioning unit of an organism is a(n) ________.

cell

29. What multipotent stem cells from children sometimes banked by parents?

cells from the umbilical cord and from baby teeth

19. Which of the following is an example of a normal physiologic process that uses a positive feedback loop?

childbirth

16. AB → A + B is a general notation for a(n) ________ reaction.

decomposition

13. Cancer cells can be characterized as "generic" cells that perform no specialized body function. Thus cancer cells lack ________.

differentiation

32. What do osmosis

diffusion, filtration, and the movement of ions away from like charge all have in common? In what way do they differ?, These four phenomena are similar in the sense that they describe the movement of substances down a particular type of gradient. Osmosis and diffusion involve the movement of water and other substances down their concentration gradients, respectively. Filtration describes the movement of particles down a pressure gradient, and the movement of ions away from like charge describes their movement down their electrical gradient.

7. The diffusion of substances within a solution tends to move those substances ________ their ________ gradient.

down; concentration

Visit this website (http://openstaxcollege.org/l/ptable) to view the periodic table. In the periodic table of the elements

elements in a single column have the same number of electrons that can participate in a chemical reaction. These electrons are known as "valence electrons." For example, the elements in the first column all have a single valence electron—an electron that can be "donated" in a chemical reaction with another atom. What is the meaning of a mass number shown in parentheses?, The mass number is the total number of protons and neutrons in the nucleus of an atom.

35. Magnesium is an important element in the human body

especially in bones. Magnesium's atomic number is 12. Is it stable or reactive? Why? If it were to react with another atom, would it be more likely to accept or to donate one or more electrons?, Magnesium's 12 electrons are distributed as follows: two in the first shell, eight in the second shell, and two in its valence shell. According to the octet rule, magnesium is unstable (reactive) because its valence shell has just two electrons. It is therefore likely to participate in chemical reactions in which it donates two electrons.

7. A scientist wants to study how the body uses foods and fluids during a marathon run. This scientist is most likely a(n) ________.

exercise physiologist

26. What organic compound do brain cells primarily rely on for fuel?

glucose

29. A phospholipid ________.

has both polar and nonpolar regions

28. Which type of stem cell gives rise to red and white blood cells?

hematopoietic

27. What are two major disadvantages of MRI scans?

high cost and the need for shielding from the magnetic signals

18. Which of the following combinations of atoms is most likely to result in a chemical reaction?

hydrogen and hydrogen

22. How many "letters" of an RNA molecule

in sequence, does it take to provide the code for a single amino acid?,. 3

6. Because they are embedded within the membrane

ion channels are examples of ________., integral proteins

11. When an atom donates an electron to another atom

it becomes, an ion

4. Together

just four elements make up more than 95 percent of the body's mass. These include ________.,oxygen, carbon, hydrogen, and nitrogen

23. The heart is within the ________.

mediastinum

7. On the periodic table of the elements

mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have ________., more than 80 neutrons each

14. Which of the following organelles produces large quantities of ATP when both glucose and oxygen are available to the cell?

mitochondria

33. Explain why the structure of the ER

mitochondria, and Golgi apparatus assist their respective functions., The structure of the Golgi apparatus is suited to its function because it is a series of flattened membranous discs; substances are modified and packaged in sequential steps as they travel from one disc to the next. The structure of Golgi apparatus also involves a receiving face and a sending face, which organize cellular products as they enter and leave the Golgi apparatus. The ER and the mitochondria both have structural specializations that increase their surface area. In the mitochondria, the inner membrane is extensively folded, which increases surface area for ATP production. Likewise, the ER is elaborately wound throughout the cell, increasing its surface area for functions like lipid synthesis, Ca++ storage, and protein synthesis.

17. After you eat lunch

nerve cells in your stomach respond to the distension (the stimulus) resulting from the food. They relay this information to ________, a control center

28. A pentose sugar is a part of the monomer used to build which type of macromolecule?

nucleic acids

18. Place the following structures in order from least to most complex organization: chromatin

nucleosome, DNA, chromosome, DNA, nucleosome, chromatin, chromosome

30. In DNA

nucleotide bonding forms a compound with a characteristic shape known as a(n) ________., double helix

36. Why is it important that DNA replication take place before cell division? What would happen if cell division of a body cell took place without DNA replication

or when DNA replication was incomplete?, During cell division, one cell divides to produce two new cells. In order for all of the cells in your body to maintain a full genome, each cell must replicate its DNA before it divides so that a full genome can be allotted to each of its offspring cells. If DNA replication did not take place fully, or at all, the offspring cells would be missing some or all of the genome. This could be disastrous if a cell was missing genes necessary for its function and health.

9. A collection of similar tissues that performs a specific function is an ________.

organ

20. CH4 is methane. This compound is ________.

organic

9. Choose the answer that best completes the following analogy: Diffusion is to ________ as endocytosis is to ________.

osmosis; pinocytosis

15. The bonding of calcium

phosphorus, and other elements produces mineral crystals that are found in bone. This is an example of a(n) ________ reaction., synthesis

27. Arrange the following terms in order of increasing specialization: oligopotency

pleuripotency, unipotency, multipotency., pleuripotency, multipotency, oligopotency, unipotency

10. A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with ________.

polar covalent bonds

14. The energy stored in a foot of snow on a steep roof is ________.

potential energy

12. Which of the following is a function of the rough ER?

production of proteins

6. Which of the following specialties might focus on studying all of the structures of the ankle and foot?

regional anatomy

21. Transcription and translation take place in the ________ and ________

respectively., nucleus; cytoplasm

11. The rough ER has its name due to what associated structures?

ribosomes

19. Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that ________.

saliva contains enzymes

12. A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n) ________.

salt

23. A substance dissociates into K+ and Cl- in solution. The substance is a(n) ________.

salt

10. The body system responsible for structural support and movement is the ________.

skeletal system

21. Which of the following is most likely to be found evenly distributed in water in a homogeneous solution?

sodium ions and chloride ions

32. The ability of an enzyme's active sites to bind only substrates of compatible shape and charge is known as ________.

specificity

26. What is a primary function of tumor suppressor genes?

stop certain cells from dividing

12. Adenosine triphosphate (ATP) is an important molecule because it ________.

stores energy for use by body cells

11. Metabolism can be defined as the ________.

sum of all chemical reactions in an organism

22. The lumbar region is ________.

superior to the popliteal region

18. Stimulation of the heat-loss center causes ________.

sweat glands to increase their output

34. When you open a bottle of sparkling water

the carbon dioxide gas in the bottle form bubbles. If the bottle is left open, the water will eventually "go flat." Explain these phenomena in terms of atmospheric pressure., In a sealed bottle of sparkling water, carbon dioxide gas is kept dissolved in the water under a very high pressure. When you open the bottle, the pressure of the gas above the liquid changes from artificially high to normal atmospheric pressure. The dissolved carbon dioxide gas expands, and rises in bubbles to the surface. When a bottle of sparkling water is left open, it eventually goes flat because its gases continue to move out of solution until the pressure in the water is approximately equal to atmospheric pressure.

23. Which of the following is not made out of RNA?

the ribosome

5. Visit this link (http://openstaxcollege.org/l/mitosis) to learn about mitosis. Mitosis results in two identical diploid cells. What structures form during prophase?

the spindle

10. Choose the term that best completes the following analogy: Cytoplasm is to cytosol as a swimming pool containing chlorine and flotation toys is to ________.

the water

22. Jenny mixes up a batch of pancake batter

then stirs in some chocolate chips. As she is waiting for the first few pancakes to cook, she notices the chocolate chips sinking to the bottom of the clear glass mixing bowl. The chocolate-chip batter is an example of a ________., suspension

8. Nitrogen has an atomic number of seven. How many electron shells does it likely have?

two

26. Which of the following imaging studies can be used most safely during pregnancy?

ultrasound

37. What regulatory processes would your body use if you were trapped by a blizzard in an unheated

uninsulated cabin in the woods?,Any prolonged exposure to extreme cold would activate the brain's heat-gain center. This would reduce blood flow to your skin, and shunt blood returning from your limbs away from the digits and into a network of deep veins. Your brain's heat-gain center would also increase your muscle contraction, causing you to shiver. This increases the energy consumption of skeletal muscle and generates more heat. Your body would also produce thyroid hormone and epinephrine, chemicals that promote increased metabolism and heat production.

43. If the disaccharide maltose is formed from two glucose monosaccharides

which are hexose sugars, how many atoms of carbon, hydrogen, and oxygen does maltose contain and why?, Maltose contains 12 atoms of carbon, but only 22 atoms of hydrogen and 11 atoms of oxygen, because a molecule of water is removed during its formation via dehydration synthesis.

2. Watch this video (http://openstaxcollege.org/l/endomembrane1) to learn about the endomembrane system

which includes the rough and smooth ER and the Golgi body as well as lysosomes and vesicles. What is the primary role of the endomembrane system?, Processing, packaging, and moving materials manufactured by the cell.

39. If a bullet were to penetrate a lung

which three anterior thoracic body cavities would it enter, and which layer of the serous membrane would it encounter first? , The bullet would enter the ventral, thoracic, and pleural cavities, and it would encounter the parietal layer of serous membrane first.

34. Oxygen

whose atomic number is eight, has three stable isotopes: 16O, 17O, and 18O. Explain what this means in terms of the number of protons and neutrons., Oxygen has eight protons. In its most abundant stable form, it has eight neutrons, too, for a mass number of 16. In contrast, 17O has nine neutrons, and 18O has 10 neutrons.

44. Once dietary fats are digested and absorbed

why can they not be released directly into the bloodstream?, All lipids are hydrophobic and unable to dissolve in the watery environment of blood. They are packaged into lipoproteins, whose outer protein envelope enables them to transport fats in the bloodstream.

40. When you do a load of laundry

why do you not just drop a bar of soap into the washing machine? In other words, why is laundry detergent sold as a liquid or powder?, Recall that the greater the surface area of the reactants, the more quickly and easily they will interact. It takes energy to separate particles of a substance. Powder and liquid laundry detergents, with relatively more surface area per unit, can quickly dissolve into their reactive components when added to the water.

21. To make a banana split

you halve a banana into two long, thin, right and left sides along the ________., midsagittal plane

37. In a hurry one day

you merely rinse your lunch dishes with water. As you are drying your salad bowl, you notice that it still has an oily film. Why was the water alone not effective in cleaning the bowl?, Water is a polar molecule. It has a region of weakly positive charge and a region of weakly negative charge. These regions are attracted to ions as well as to other polar molecules. Oils are nonpolar, and are repelled by water.