exam 2 (practice questions)

Question 1

why should you use a light microscope if you want to film the movement of chromosomes during cell division?

Answer 1

because the specimen is alive

• although light microscopes have far less resolution than electron microscopes, light microscopy is the only technique that permits one to observe living cells

Question 2

what is cell fractionation?

Answer 2

laboratory technique that is used to separate the various components of cells

(like taking apart a cell to examine the little pieces of it)

Question 3

two cells have the same volume but different surface areas. the cell with the larger surface area is likely to ______________

Answer 3

be involved in the rapid uptake of compounds from their cell’s environment

Question 4

in cells, the greater the surface area, the greater the ______________

Answer 4

potential for transport

Question 5

name 3 things that are likely to limit the maximum size of a cell

Answer 5

1. cell’s surface-to-volume ratio
2. time it takes a molecule to diffuse across a cell
3. shape of the cell

(mainly the surface-to volume ratio) and everything else just kinda means the same thing)

Question 6

do prokaryotic cells contain the following organelles:?

1. mitochondria
2. ribosomes
3. plasma membrane
4. cytosol
5. DNA
6. nucleus

Answer 6

1. no, only eukaryotic cells have membrane bound organelles
2. yes, ribosomes are required for protein synthesis and present in both types of cells
3. yes, all cells have plasma membranes
4. yes, volume enclosed by plasma membrane in prokaryotic cells is the cytosol
5. yes, all living cells contain DNA
6. no, prokaryotes are named for their lack of a nucleus

Question 7

A substance moving from outside the cell into the cytoplasm must pass through __________

Answer 7

the plasma membrane

Question 8

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells?

Answer 8

eukaryotic cells are compartmentalized (due to the presence of membrane-bound organelles) , which allows for specialization

Question 9

which 3 features do prokaryotes and eukaryotes have in common?

Answer 9

ribosomes, plasma membrane, and cytoplasm

Question 10

protists cells are ___________ that can ___________

Answer 10

eukaryotes; photosynthesize

Question 11

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane?

Answer 11

proteins and ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores

Question 12

when do chromosomes appear in an obvious form in the cell?

Answer 12

although they appear more compact as the cell prepares to divide, they are always present in the cell, even when cells are not actively synthesizing proteins

Question 13

where is DNA housed?

Answer 13

in the nucleus

Question 14

which 3 groups of organelles are mainly involved in synthesizing molecules needed by the cell?

Answer 14

ribosomes, rough ER, smooth ER

Question 15

function of the rough endoplasmic reticulum

Answer 15

manufacture of proteins for the end-membrane system

Question 16

function of the smooth endoplasmic reticulum

Answer 16

synthesis of essential lipids such as phospholipids and cholesterol

Question 17

function of the Golgi apparatus

Answer 17

further modify and sort the lipids and proteins produced by the ERs and prepare them for their destinations in either lysosomes, plasma membrane, or excretion

Question 18

You would expect a cell with an extensive Golgi apparatus to __________

Answer 18

secrete large amounts of protein

Question 19

function of vesicles

Answer 19

carry and transport material that the cell needs

Question 20

transmembrane proteins vs. soluble proteins

Answer 20

transmembrane proteins: proteins embedded within cell membrane, allows them to interact with both inside and outside of the cell
- play roles in cell communication, transport of molecules across membrane, and structural support for membrane

soluble proteins: found in watery parts of cell, like cytoplasm or nucleus and are not embedded within membranes
- have various functions like catalyzing chemical reactions, providing structural support, and acting as messengers or signals within the cell

transmembrane proteins are “anchored”, soluble proteins are “floating”

Question 21

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized __________

Answer 21

in the rough ER

all of the membrane proteins of the endomembrane systems are made in the rough ER

Question 22

why is the mitochondrial outer membrane have a lipid composition that is different from the lipid composition of other cells?

Answer 22

mitochondria are not part of the endomembrane system and must synthesize their own lipids

Question 23

chloroplasts and mitochondria are similar in the way that they ______________

Answer 23

synthesize their own proteins

chloroplasts and mitochondria can synthesize some of their own proteins because they contain DNA and ribosomes

Question 24

which type of cell would be most likely to have the largest number of mitochondria?

Answer 24

cells with the highest energy demand (such as muscle cells in the legs of a marathon runner)

Question 25

where are the ribosomes of a mitochondria found?

Answer 25

in the matrix

Question 26

the folds of the inner mitochondrial membrane are called _________

Answer 26

cristae

Question 27

true or false: mitochondria have more than one membrane

Answer 27

true

Question 28

microtubules and microfilaments commonly work with which organelle to perform many of their functions?

Answer 28

Golgi apparatus *microtubules guide vesicles from the ER to the Golgi and from the Golgi to the plasma membrane*

Question 29

function of centrioles

Answer 29

*only found in animal cells* - play a key role in cell division - help organize and guide the movement of chromosomes during cell division - essential for growth and repair of tissues in the body

Question 30

microtubules

Answer 30

provide structural support to cell and serve as tracks for moving materials *think of them as the highways of the cell* - long, hollow tubes made of protein subunits called tubulin

Question 31

microfilaments

Answer 31

responsible for movement and shape changes *like the cell's muscles* - thin, thread-like structures responsible for movement, including cell contraction in animals

Question 32

intermediate filaments

Answer 32

provide mechanical support and stability to cells, helping them maintain their shape and resist physical stress *think of as "structural cables" of the cell* - type of protein fiber - resist stretching

Question 33

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following?

Answer 33

motor proteins

Question 34

motor proteins

Answer 34

- "movers" of the cell - specialized proteins that use energy to transport various materials - play critical role in movement of cilia and flagella

Question 35

Basal bodies are most closely associated with which cell components?

Answer 35

cilia *microtubule assembly of cilium or flagella is anchored in the cell of a basal body*

Question 36

Dye injected into a plant cell might be able to enter an adjacent cell through __________

Answer 36

plasmodesmata

Question 37

plasmodesmata

Answer 37

known for role in facilitating communication and transport between PLANT cells - connect neighboring plant cells, allowing them to exchange various molecules

Question 38

tight junctions & gap junctions

Answer 38

**tight junctions**: create barriers/tight seal and control passage of substance between cells - ex. no fluid leaks b/w cells b/c of them **gap junctions**: channels that allow direct communication b/w cells by allowing exchange of ions, small molecules, and signaling (essential for coordination & communication)

Question 39

Which statement correctly describes a common characteristic of a plant cell wall and an animal cell extracellular matrix?

Answer 39

both are permeable to water and small solutes

Question 40

substrate-level phosphorylation

Answer 40

process in which a phosphate group is transferred from a high-energy substrate directly to ADP, forming ATP - occurs in both glycolysis and citric acid cycle (not in oxidative phosphorylation, aka ETC, b/c that is indirect creation of ATP)

Question 41

relationship b/w reduction/oxidation and potential energy

Answer 41

- reduced: loses potential energy (moves to a lower energy state) - oxidized: gains potential energy (moves to a higher energy state)

Question 42

H+ atom losing or gaining is synonymous with (in terms of reduction and oxidation)

Answer 42

electron

Question 43

NAD+ is reduced to NADH during which cycles?

Answer 43

glycolysis, pyruvate oxidation, and the citric acid cycle

Question 44

why are carbs and fats frequently considered high-energy foods?

Answer 44

they contain many electrons associated with hydrogen atoms

Question 45

substrate-level phosphorylation accounts for approximately what % of ATP formed by the reactions of *glycolysis*?

Answer 45

100%

Question 46

what is the NET production of glycolysis?

Answer 46

2 NADH, 2 pyruvate, and 2 ATP

Question 47

during which metabolic process is MOST of the CO2 from the catabolism of glucose released?

Answer 47

oxidation of pyruvate to acetyl-coA

Question 48

which electron carriers function in the citric acid cycle?

Answer 48

NADH and FADH2

Question 49

what is formed by the removal of a carbon from a molecule of pyruvate?

Answer 49

acetyl CoA

Question 50

true or false: ETC consists of a series of redox reactions

Answer 50

true

Question 51

which sequence describes the path by which electrons travel downhill energetically in *aerobic* respiration?

Answer 51

glucose → NADH → electron transport chain → oxygen

Question 52

the synthesis of ATP by oxidative phosphorylation, using the energy released by the movement of protons across the membrane down their electrochemical gradient, is an example of which process?

Answer 52

coupling of an endergonic reaction to an exergonic reaction

Question 53

a person who follows a strict diet and loses an excessive amount of weight lost the fat as?

Answer 53

CO2 and H2O

Question 54

the *immediate* energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the

Answer 54

H+ concentration gradient across the membrane holding ATP synthase

Question 55

in mitochondria, exergonic redox reactions

Answer 55

are coupled via phosphorylated intermediates to endergonic processes

Question 56

when electrons flow along the ETC of mitochondria, what happens to the pH of the matrix?

Answer 56

it increases

Question 57

most CO2 from catabolism is released during

Answer 57

the citric acid cycle

Question 58

in autotrophic bacteria, where is chlorophyll located?

Answer 58

in folded regions of the plasma membrane

Question 59

the oxygen released by photosynthesis is produced by which of the following processes?

Answer 59

splitting water molecules

Question 60

what happens to the free energy released as electrons are passed from photosystem II to photosystem I through a series of electron carriers?

Answer 60

it is used to establish and maintain a proton gradient

Question 61

which molecule is the final electron acceptor for electrons from photosystem I?

Answer 61

CO2

Question 62

what process is directly associated with photosystem I?

Answer 62

receiving electrons from the thylakoid membrane ETC

Question 63

what is unique about the cyclic electron flow compared to the linear electron flow?

Answer 63

cyclic electron flow uses photosystem I ONLY - produced ATP, but not NADPH or oxygen

Question 64

where are ATP synthase complexes located in plant cells?

Answer 64

thylakoid membrane and inner mitochondrial membrane