Micro Study Questions 4.2

25) You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell A) Has 9 pairs + 2 flagella. B) Has a mitochondrion. C) Has a cell wall. D) Lives in an extreme environment. E) Has a nucleus.

C) Has a cell wall.

What is the fate of a bacterium engulfed by a white blood cell through phagocytosis?

The cell consumes the bacterium and begins digesting it and uses its parts for energy.

How does the nuclear membrane differ from the plasma membrane?

The cell membrane is a lipid bilayer that surrounds the entire cell. It is a lipid bilayer in the form of a continuous sheet. The nuclear membrane is not a continuous sheet, but rather is made up of a series of vesicles that come together to form the envelope around the nucleus.

Why do human fat cells possess very few mitochondria, while human muscle cells can possess as many as 2,000 mitochondria?

Fat cells burns energy quicker than muscle cells, which stores energy.

What will happen to a red blood cell placed in a hypotonic solution such as distilled water? How about a hypertonic solution? How about an isotonic solution?

Hypotonic- more water OUTSDE the cell, water diffuses Hypertonic- more water INSIDE the cell, water diffuses Isotonic- balanced water movement

Describe the structure of a phospholipid. How do its two main regions interact with water? How are phospholipids arranged in two layers to form a plasma membrane that interacts with water on both surfaces?

-External and Internal environment made of cholesterol, phospholipid, protein -When cellular membranes form, phospholipids assemble into two layers because of these hydrophilic and hydrophobic properties. The phosphate heads in each layer face the aqueous or watery environment on either side, and the tails hide away from the water between the layers of heads, because they are hydrophobic.

Describe the three primary types of connections between animal cells?

1. Tight Junction- 2 cells with water-tight seal 2. Desmosomes- "Velcro" keeps cells together 3. Gap Junctions- "passageways" allows material to pass

Give two examples of ways in which proteins are modified within the Golgi apparatus.

1.) protein sorting 2.) targeted secretion (secretion is not uniformon the plasma membrane) 3.) biosynthesis and covalent modifications ofglycolipids and sphingomyelin 4.) covalent modifications of proteins 5.) signaling

What are the three chief purposes of the cytoskeleton?

the cytoskeleton gives a cell its shape, offers support, and facilitates movement through three main components: microfilaments, intermediate filaments, and microtubules.

43) Which of the following are NOT energy reserves? A) Carboxysomes. B) Polysaccharide granules. C) Lipid inclusions. D) Sulfur granules. E) Metachromatic granules.

A) Carboxysomes. The function of the carboxysome is to concentrate CO2 with close proximity to RuBisCO, eliminating the competitive reaction with oxygen. Thus, carboxysomes are the site of carbon dioxide (CO2) fixation.

19) Which of the following is NOT a chemical component of a bacterial cell wall? A) Cellulose B) Peptidoglycan C) Teichoic acids D) Peptide chains E) N-acetylmuramic acid

A) Cellulose

24) Which of the following is NOT a possible function of magnetosomes? A) Get cells to the North Pole B) Protect cells from hydrogen peroxide accumulation C) Store iron D) Locate suitable environments

A) Get cells to the North Pole

6) Which of the following is NOT a characteristic of the plasma membrane? A) Maintains cell shape B) Is composed of a phospholipid bilayer C) Contains proteins D) Is the site of cell wall formation E) Is selectively permeable

A) Maintains cell shape The Plasma Membrane -Phospholipid bilayer -Peripheral proteins -Integral proteins -Transmembrane proteins -Sterols -Glycocalyx carbohydrates Cytoplasm- The substance inside the plasma membrane

41) What will happen if a bacterial cell is placed in 10% NaCl with penicillin? A) The cell will plasmolyze. B) The cell will undergo osmotic lysis. C) Water will enter the cell. D) Penicillin will diffuse into the cell. E) No change will result; the solution is isotonic.

A) The cell will plasmolyze. Plasmolysis is the process in which cells lose water in a hypertonic solution

28) In Figure 4.3, which diagram of a cell wall is a toxic cell wall? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

A) a

32) In Figure 4.3, which diagram of a cell wall contains teichoic acids? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

A) a

34) Where are phospholipids most likely found in a prokaryotic cell? A) Flagella B) Around organelles C) Plasma membrane D) Ribosomes E) B and C

C) Plasma membrane The Plasma Membrane- § Phospholipid bilayer § Peripheral proteins § Integral proteins § Transmembrane proteins § Sterols § Glycocalyx carbohydrates

42) Which one of the following pairs is mismatched? A) Metachromatic granules — phosphate storage B) Lipid inclusions — energy reserve C) Ribosomes — protein storage D) Sulfur granules — energy reserve E) Gas vacuoles — flotation

C) Ribosomes — protein storage

33) In Figure 4.3, which diagram of a cell wall contains porins? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

B) A Porins are beta barrel proteins that cross a cellular membrane and act as a pore, through which molecules can diffuse.

8) Which of the following statements is true? A) Endospores are for reproduction. B) Endospores allow a cell to survive environmental changes. C) Endospores are easily stained in a Gram stain. D) A cell produces one endospore and keeps growing. E) A cell can produce many endospores.

B) Endospores allow a cell to survive environmental changes. Endospores - Resting cells § Resistant to desiccation, heat, chemicals § Bacillus, Clostridium § Sporulation: Endospore formation § Germination: Return to vegetative state

7) Which of the following have a cell wall? A) Protoplasts B) Fungi C) L forms D) Mycoplasmas E) Animal cells

B) Fungi

10) Which of the following organelles most closely resembles a prokaryotic cell? A) Nucleus B) Mitochondrion C) Golgi complex D) Vacuole E) Cell wall

B) Mitochondrion Mitochondrion: Cellular respiration

40) What will happen if a bacterial cell is placed in distilled water with lysozyme? A) The cell will plasmolyze. B) The cell will undergo osmotic lysis. C) Water will leave the cell. D) Lysozyme will diffuse into the cell. E) No change will result; the solution is isotonic.

B) The cell will undergo osmotic lysis.

15) Which of the following statements about prokaryotic cells is generally false? A) They have a semirigid cell wall. B) They are motile by means of flagella. C) They possess 80S ribosomes. D) They reproduce by binary fission. E) They lack membrane-bound nuclei.

C) They possess 80S ribosomes.

4) The best definition of osmotic pressure is A) The movement of solute molecules from a higher to a lower concentration. B) The force with which a solvent moves across a semipermeable membrane from a higher to a lower concentration. C) The movement of a substance across a semipermeable membrane from a higher to a lower concentration. D) The active transport of a substance out of a cell to maintain equilibrium. E) The movement of solute molecules from a lower to a higher concentration across a semipermeable membrane.

B) The force with which a solvent moves across a semipermeable membrane from a higher to a lower concentration. Osmotic pressure: The pressure needed to stop the movement of water across the membrane

30) In Figure 4.3, which diagram of a cell wall is decolorized by acetone-alcohol? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

B) b

27) In Figure 4.3, which diagram of a cell wall is a gram-negative cell wall? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

B) b Gram-Negative § Endotoxin § Tetracycline sensitive § Thin peptidoglycan § Outer membrane § Periplasmic space

31) In Figure 4.3, which diagram of a cell wall is resistant to many antibiotics (e.g., penicillin)? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

B) b Gram-Positive- Thick peptidoglycan § Teichoic acids § Disrupted by lysozyme § Penicillin sensitive

38) Figure 4.4 shows movement across a plasma membrane. Which figure best represents simple diffusion? A) a B) b C) c D) d E) e

B) b Simple Diffusion: Movement of a solute from an area of high concentration to an area of low concentration

5) By which of the following mechanisms can a cell transport a substance from a lower to a higher concentration? A) Simple diffusion B) Facilitated diffusion C) Active transport D) Extracellular enzymes E) Aquaporins

C) Active transport

26) Fimbriae and pili differ in that pili A) Are composed of pilin. B) Are composed of flagellin. C) Are used to transfer DNA. D) Are used for motility. E) Are used for attachment.

C) Are used to transfer DNA. Fimbriae allow attachment Pili- Facilitate transfer of DNA from one cell to another § Gliding motility § Twitching motility

29) In Figure 4.3, which diagram of a cell wall has a wall that protects against osmotic lysis? A) a B) b C) Both a and b D) Neither a nor b E) Can't tell

C) Both a and b

36) Which of the following is NOT found in mitochondria and prokaryotes? A) Circular chromosome B) 70S ribosomes C) Cell wall D) Binary fission E) ATP-generating mechanism

C) Cell wall

22) In bacteria, photosynthetic pigments are found in A) Chloroplasts. B) Cytoplasm. C) Chromatophores. D) Mesosomes. E) Ribosomes.

C) Chromatophores.

17) Which of the following structures is NOT found in prokaryotic cells? A) Flagellum B) Axial filament C) Cilium D) Pilus E) Peritrichous flagella

C) Cilium

2) Which of the following statements about a gram-positive cell wall is false? A) It maintains the shape of the cell. B) It is sensitive to lysozyme. C) It protects the cell in a hypertonic environment. D) It contains teichoic acids. E) It is sensitive to penicillin.

C) It protects the cell in a hypertonic environment. -Isotonic - Cells maintain normal size and shape -Hypertonic - Cells lose water osmotically and shrink and shrivel -Hypotonic - Cells gain water osmotically and swell and may burst

21) Which of the following terms best describes the cell in Figure 4.2? A) Peritrichous flagella B) Amphitrichous flagella C) Lophotrichous flagella D) Monotrichous flagella E) Axial filament

C) Lophotrichous flagella Lophotrichous are those bacteria which have multiple flagella at one polar end or multiple flagella at one point

3) Which of the following statements best describes what happens when a bacterial cell is placed in a solution containing 5% NaCl? A) Sucrose will move into the cell from a higher to a lower concentration. B) The cell will undergo osmotic lysis. C) Water will move out of the cell. D) Water will move into the cell. E) No change will result; the solution is isotonic.

C) Water will move out of the cell.

37) Figure 4.4 shows movement across a plasma membrane. Which figure best represents a specific transporter protein? A) a B) b C) c D) d E) e

C) c -Facilitated Diffusion: Solute combines with a transporter protein in the membrane -Active transport: Requires a transporter protein and ATP -Group translocation: Requires a transporter protein and PEP

14) Which drawing in Figure 4.1 is a bacillus? A) a B) b C) c D) d E) e

C. (_____)

What is the main function of chloroplasts?

Chloroplasts are the site of photosynthesis, where light energy is converted into chemical energy of food molecules.

20) Which of the following is NOT part of the active transport process? A) Plasma membrane B) Transporter proteins C) ATP D) Cell wall E) None of the above

D) Cell wall -Passive Transport: Molecular movement occurs spontaneously, without the input of energy. • Simple Diffusion • Facilitated Diffusion (Carrier-Mediated) • Osmosis -Active Transport: Carrier-mediated with the movement with use of energy (ATP)

9) Which of the following pairs is mismatched? A) Endoplasmic reticulum — internal transport B) Golgi complex — secretion C) Mitochondria — ATP production D) Centrosome — food storage E) Lysosome — digestive enzymes

D) Centrosome — food storage Centrosome: Consists of protein fibers and centrioles

44) Which of the following pairs is NOT a functionally analogous pair? A) Nucleus — nuclear region B) Mitochondria — prokaryotic plasma membrane C) Chloroplasts — thylakoids D) Cilia — pili E) 9+2 flagella — bacterial flagella

D) Cilia — pili

45) The bacteria on the outside of termite protozoa A) Digest cellulose. B) Steer the protozoan to food. C) Are transient microbiota. D) Propel the protozoan. E) None of the above

D) Propel the protozoan.

23) The difference between simple diffusion and facilitated diffusion is that facilitated diffusion A) Can move materials from a higher to a lower concentration. B) Can move materials from a lower to a higher concentration. C) Requires ATP. D) Requires transporter proteins. E) Doesn't require ATP.

D) Requires transporter proteins.

16) Which of the following statements about gram-negative cell walls is false? A) They protect the cell in a hypotonic environment. B) They have an extra outer layer composed of lipoproteins, lipopolysaccharides, and phospholipids. C) They are toxic to humans. D) They are sensitive to penicillin. E) Their Gram reaction is due to the outer membrane.

D) They are sensitive to penicillin. Gram-Positive § Thick peptidoglycan § Teichoic acids § Disrupted by lysozyme § Penicillin sensitive Gram-Negative § Endotoxin § Tetracycline sensitive § Thin peptidoglycan § Outer membrane § Periplasmic space

13) Which drawing in Figure 4.1 is streptococci? A) a B) b C) c D) d E) e

D. oooooo

How is the location of the DNA in a prokaryotic cell different from that of a eukaryotic cell?

DNA: Eukaryotic DNA is stored in a nucleus, whereas prokaryotic DNA is in the cytoplasm in the form of a nucleoid

35) Where are phospholipids most likely found in a eukaryotic cell? A) Flagella B) Around organelles C) Plasma membrane D) Ribosomes E) B and C

E) B and C

18) Which of the following statements about the glycocalyx is false? A) It may be composed of polysaccharide. B) It may be composed of polypeptide. C) It may be responsible for virulence. D) It is used to adhere to surfaces. E) It protects from osmotic lysis.

E) It protects from osmotic lysis.

1) Which of the following is NOT a distinguishing characteristic of prokaryotic cells? A) Their DNA is not enclosed within a membrane. B) They lack membrane-enclosed organelles. C) They have cell walls containing peptidoglycan. D) Their DNA is not associated with histones. E) They lack a plasma membrane.

E) They lack a plasma membrane. The prokaryotic cell is simple, small, and contains no organelles

39) Figure 4.4 shows movement across a plasma membrane. Which figure best represents an aquaporin? A) a B) b C) c D) d E) e

E) e Aquaporins (water channels)

List the four primary types of membrane proteins and their function.

Enzyme- A type of protein that speeds up a chemical reaction in a living thing Channel Protein-This protein acts as a tunnel for larger molecules in facilitated diffusion Adhesion Protein- Membrane proteins that help link cells together Anchor Protein- Anchors to the plasma membrane.

11) Which drawing in Figure 4.1 is a tetrad? A) a B) b C) c D) d E) e

OO OO

What are the five key functions of plant vacuoles?

Plant vacuole functions include nutrient storage, waste management, predator deterrence, sexual reproduction, and physical support.

List the two divisions of the endoplasmic reticulum, and at least one function of each.

Rough- Modifies proteins that will be shipped elsewhere in the organism Smooth- Synthesizes lipids and detoxifies molecules

Why does it sometimes cost energy to move molecules across a membrane?

Sometimes charge molecules and large molecules need help carrying molecules uphill against its concentration gradient.

In what way does a membrane function improperly in an individual with cystic fibrosis? What are the key symptoms of this disorder?

The change in the transmembrane protein affecting mostly the lungs due to the loss of amino acid which changes the structured of a protein. Thick mucus allows bacteria to thrive. Resp infections, cough, SOB

How does your immune system tell the difference between your own cells and foreign cells such as bacteria?

The immune system protects the body from possibly harmful substances by recognizing and responding to antigens. Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain other antigens.

53. The transport of water across a membrane from a solution of lower solute concentration to a solution of higher solute concentration is best describe as: a) osmosis. b) facilitated diffusion. c) receptor-mediated transport. d) active transport. e) general diffusion.

a) osmosis. Osmotic pressure: The pressure needed to stop the movement of water across the membrane

49. Hydrophobic molecules can pass freely through the plasma membrane, but molecules with electrical charges (such as ions and polar molecules) are impeded by the hydrophobic core. For this reason, plasma membranes can be considered: a) partially permeable. b) impermeable. c) hydrophobic. d) hydrophilic. e) None of these terms properly describe plasma membranes.

a) partially permeable.

12) Which drawing in Figure 4.1 possesses an axial filament? A) a B) b C) c D) d E) e

a. spiral Rotation causes cell to move

47. Which of the following statements about prokaryotes is incorrect? a) Prokaryotes appeared on earth before eukaryotes. b) Prokaryotes have circular pieces of DNA within their nuclei. c) Prokaryotes contain cytoplasm. d) Prokaryotes contain ribosomes. e) Some prokaryotes can conduct photosynthesis.

b) Prokaryotes have circular pieces of DNA within their nuclei. The prokaryotic cell is simple, small, and contains no organelles

61. Cell walls: a) only occur in plant cells. b) are not completely solid, having many small pores. c) confer less structural support than the plasma membrane. d) dissolve when a plant dies. e) are made primarily from phospholipids.

b) are not completely solid, having many small pores.

63. In plant cells, chloroplasts: a) serve the same purpose that mitochondria serve in animal cells. b) are the site of conversion of light energy into chemical energy. c) play an important role in the breakdown of plant toxins. d) have their own linear strands of DNA. e) Both a) and b) are correct.

b) are the site of conversion of light energy into chemical energy. Chloroplast: Photosynthesis

56. The largest structure in a eukaryotic cell is the ______ and it is surrounded by ______ membrane(s). a) nucleus; one b) nucleus; two c) Golgi apparatus; one d) mitochondrion; two e) mitochondrion; one

b) nucleus; two

60. Given that a cell's structure reflects its function, what function would you predict for a cell with a large Golgi apparatus? a) movement b) secretion of digestive enzymes c) transport of chemical signals d) rapid replication of genetic material and coordination of cell division e) attachment to bone tissue.

b) secretion of digestive enzymes Processes and packages protein, lipids, and other molecules for export to other parts of the organism

58. Which of the following statements about mitochondria is correct? a) Mitochondria are found in both eukaryotes and prokaryotes. b) There tend to be more mitochondria in fat cells than in liver cells. c) Most plant cells contain mitochondria. d) Mitochondria may have originated evolutionarily as photosynthetic bacteria. e) All of the above are correct.

c) Most plant cells contain mitochondria. harvest energy to be used for cellular functions

52. The movement of molecules across a membrane from an area of high concentration to one of low concentration is best described as: a) active transport. b) inactivated transport. c) passive transport. d) channel-mediated diffusion. e) electron transport.

c) passive transport. Passive Transport: Molecular movement occurs spontaneously, without the input of energy. • -Simple Diffusion • -Facilitated Diffusion (Carrier-Mediated) • -Osmosis

54. In an experiment, you measure the concentration of a polar molecule inside and outside a cell. You find that the concentration is high and gradually increasing inside the cell. You also measure the ATP concentration inside the cell and find that it is dropping. What is your best hypothesis for the process you are observing? a) facilitated diffusion b) passive transport c) simple diffusion d) active transport e) endocytosi

d) active transport Active transport: Requires a transporter protein and ATP the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy

50. Drugs called beta-blockers do all of the following except: a) reduce high blood pressure. b) block signaling through adrenaline receptors. c) reduce outward symptoms of anxiety. d) bind to the cytoplasmic side of a receptor protein. e) reduce the effects of adrenaline on the heart.

d) bind to the cytoplasmic side of a receptor protein

51. Cellular "fingerprints": a) are exposed on the cytoplasmic side of the membrane. b) are made from cholesterol. c) are "erased" by the HIV virus. d) can help the immune system distinguish "self " from "non-self." e) All of the above are correct.

d) can help the immune system distinguish "self " from "non-self."

55. Which of the following allows the passage of small molecules between animal cells? a) nucleoli b) tight junctions c) desmosomes d) gap junctions e) black holes

d) gap junctions Gap junctions are a specialized intercellular connection between a multitude of animal cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.

57. The cytoskeleton: a) is a viscous fluid found in all cells. b) fills a cell's nucleus but not the other organelles. c) gives an animal cell shape and support, but cannot control movement. d) helps to coordinate intracellular movement of organelles and molecules. e) All of the above are correct

d) helps to coordinate intracellular movement of organelles and molecules. Cytoskeleton: Microfilaments, intermediate filaments, microtubules

46. Which of the following statements about the cell theory is correct? a) All living organisms are made up of one or more cells. b) All cells arise from other, pre-existing cells c) All eukaryotic cells contain symbiotic prokaryotes. d) All prokaryotic cells contain symbiotic eukaryotes. e) Both a) and b) are correct.

e) Both a) and b) are correct.

48. Which of the following facts supports the claim that mitochondria developed from bacteria that, long ago, were incorporated into eukaryotic cells by the process of phagocytosis? a) Mitochondria have flagella for motion. b) Mitochondria have proteins for the synthesis of ATP. c) Mitochondria are the "powerhouses" of the cell. d) Mitochondria are small and easily transported across cell membranes. e) Mitochondria have their own DNA.

e) Mitochondria have their own DNA.

62. Which one of the following organelles is not found in both plant and animal cells? a) nucleus b) rough endoplasmic reticulum c) mitochondrion d) smooth endoplasmic reticulum e) central vacuole

e) central vacuole The central vacuole is a large vacuole found inside of plant cells. A vacuole is a sphere filled with fluid and molecules inside a cell. The central vacuole stores water and maintains turgor pressure in a plant cell.

59. Which of the following organelles is not present in animal cells? a) lysosome b) Golgi apparatus c) rough endoplasmic reticulum d) mitochondrion e) chloroplast

e) chloroplast Chloroplast: Photosynthesis

Give two examples of cases in which cells of your body use endocytosis.

endocytos is the uptake of molecules through plasma membrane invagination and vacuole/vesicle formation. Pinocytosis (cell drinking) describes the internalization of extracellular fluid and small macromolecules by means of small vesicles. Phagocytosis (cell eating) describes the ingestion of large particles such as cell debris and whole microorganisms by means of large vesicles.

Why can some molecules diffuse directly across a phospholipid bilayer, while other molecules can only cross the membrane with the assistance of a transport protein?

some molecules can diffuse across the lipid bi layer but others cannot. Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly. A transport protein is a protein that serves the function of moving other materials within an organism. Carrier proteins are proteins involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane

List three functions of a plant's cell wall.

structure, support, and protection for the cell