exam 2 questions

Question 1

which of the following statements is NOT part of the cell theory?

Answer 1

eukaryotic cells have evolved from prokaryotic cells

Question 2

all cells have all of the following except

a) plasma membrane
b) genetic material
c) cytoplasm
d) cell wall

Answer 2

cell wall

Question 3

eukaryotic cells are more complex than prokaryotic cells. which of the following are found only in a eukaryotic cell?a) cell wall

b) plasma membrane
c) ER
d) ribosomes

Answer 3

ER

Question 4

which of the following are differences between bacteria and archaea?

Answer 4

the molecular architecture of their cell walls

Question 5

the cytoskeleton includes

Answer 5

intermediate filaments made of twisted fibers of vimentin and keratin

Question 6

the smooth ER is

Answer 6

the site of lipid and membrane synthesis

Question 7

plasmodesmata in plants and gap junctions in animals are functionally similar in that

Answer 7

they form channels between cells that allow diffusion of small molecules

Question 8

the most important factor that limits the size of a cells is the

Answer 8

surface area-to-volume ratio of the cell

Question 9

all eukaryotic cells possess each of the following except

a) mitochondria
b) cell wall
c) cytoskeleton
d) nucleus

Answer 9

cell wall

Question 10

adherens junctions, which contain cadherin, are found in all animals. Given this, which of the following predictions is most likely?

Answer 10

cadherins would be found in the ancestor to all animals

Question 11

different motor proteins like kinesin and myosin are similar in that they can

Answer 11

use e from ATP to produce movement

Question 12

the protein sorting pathway involves the following organelles/compartments in order

Answer 12

RER, transport vesicle, Golgi, final destination

Question 13

chloroplasts and mitochondria have many common features bc both

Answer 13

arose by endosymbiosis

Question 14

eukaryotic cells are composed of 3 types of cytoskeletal filaments. How are these 3 filaments similar?

Answer 14

they contribute to the shape of the cell

Question 15

the fluid mosaic model of the membrane describes the membrane as

Answer 15

made up of proteins and lipids that can freely move

Question 16

what chemical property characterizes the interior of the phospholipid bilayer

Answer 16

it is hydrophobic

Question 17

the transmembrane domain of an integral membrane protein

Answer 17

is composed of hydrophobic amino acids, often forms an a-helical structure, can cross the membrane multiple times

Question 18

the specific function of a membrane within a cell is determined by the

Answer 18

type and number of membrane proteins

Question 19

the movement of water across a membrane is dependent on

Answer 19

the solute concentration

Question 20

if a cell is in an isotonic environment, then

Answer 20

osmosis still occurs, but there is no net gain or loss of cell volume

Question 21

which of the following is NOT a mechanism for bringing material into a cell

Answer 21

exocytosis

Question 22

a bacteria cell that can alter the composition of saturated and unsaturated fatty acids in its membrane lipids is adapted to a cold environment. If this cell is shifted to a warmer environment, it will react by

Answer 22

increasing the degree of saturated fatty acids in its membrane

Question 23

what variable(s) influence(s) whether a non polar molecule can move across a membrane by passive diffusion?

Answer 23

the difference in conc of the molecule across the membrane

Question 24

which of the following does NOT contribute to the selective permeability of a biological membrane?

Answer 24

hydrogen bond formation between water and phosphate groups

Question 25

how are active transport and coupled transport related?

Answer 25

coupled transport uses the conc gradient established by active transport

Question 26

a cell can use the process of facilitated diffusion to

Answer 26

move ions or large polar molecules from a region of high conc to a region of low conc

Question 27

which of the following would be an example of a biomarker?

Answer 27

a hydrocarbon found in an ancient rock layer

Question 28

a cell that can use e from the sun, and CO2 as a carbon source is a

Answer 28

photoautotroph

Question 29

gram positive (+) and gram (-) bacteria are characterized by differences in

Answer 29

the cell wall: gram + have a thick layer of peptidoglycan and gram - have an outer membrane

Question 30

which of the following characteristics is unique to the archaea?

Answer 30

ether-linked phosolipids

Question 31

the horizontal transfer of DNA using a plasmid is an example of

Answer 31

conjugation

Question 32

the disease tuberculosis is

Answer 32

caused by a bacterial pathogen

Question 33

prokaryotes participate in the global cycling of

Answer 33

carbon and nitrogen

Question 34

which of the following is typically NOT associated with a prokaryote?

Answer 34

multiple, linear chromosomes

Question 35

the mechanisms of DNA exchange in prokaryotes share the feature of

Answer 35

horizontal transfer of info

Question 36

the cell wall in both gram-positive and gram-negative cells is

Answer 36

a target for antibiotics that affect peptidoglycan synthesis

Question 37

the three domains of life

Answer 37

consist of three different basic cell types

Question 38

ulcers and tooth decay do not appear related, but in fact both

Answer 38

can be due to bacterial infection

Question 39

bacteria lack independent internal membrane systems, but are able to perform psyn and resp, both of which use membranes. they are able to perform these functions bc

Answer 39

invaginations of the plasma membrane can provide an internal membrane surface

Question 40

plants cannot fix nitrogen, yet some plants do NOT need nitrogen from the soil. This is because...

Answer 40

of a symbiotic association with a bacterium that can fix nitrogen

Question 41

T or F: Prokaryotic conjugation which results in the transfer and insertion of the F plasmid into a recipient cell's chromosome leads to the formation an F+ cell.

Answer 41

false

Question 42

T or F: Unsaturated fatty acids make cell membranes more fluid than saturated fatty acids.

Answer 42

true

Question 43

Plasmids are distinguished from bacterial chromosomes in that

Answer 43

plasmids have few genes, bacterial chromosomes have many genes

Question 44

Which of these bulk transport mechanisms is used in animals to secrete hormones, neurotransmitters ordigestive enzymes?

Answer 44

Exocytosis

Question 45

While water continually orients phospholipids into a lipid bilayer, it does not fix thelipids permanently into position. Thus, the bilayer is considered to be ________

Answer 45

fluid

Question 46

The lipid layer that forms the foundation of cell membranes is primarily composed ofmolecules called ________.

Answer 46

phospholipids

Question 47

a cytologist is examining a tissue under an electron microscope. He notices that theendoplasmic reticulum of each cell is extremely rough in appearance and he knows thatthe rough appearance is because of the ribosomes embedded there. He asks why there areso many ribosomes. You respond,

Answer 47

"This tissue exports proteins to other areas of the body."

Question 48

The semi-fluid matrix that surrounds organelles in a cell is called the:

Answer 48

cytoplasm

Question 49

``` Which of these is not a mechanism of vertical gene transfer in prokaryotes? A) transformation B) Conjugation C) none D) transduction ```

Answer 49

none

Question 50

Prokaryotes undergo a process that produces cells that are identical. This process is called

Answer 50

binary fission

Question 51

Which of these prokaryotic organsisms is called the "Silent STD"?

Answer 51

Chlamydia trachomatis

Question 52

if the label on a slide reads Gram-positive bacillus, what would a students expect to see?

Answer 52

Purple rod shaped cells

Question 53

Osmosis is the diffusion of water across a membrane in response to the concentration ofone or more of the ________.

Answer 53

solutes

Question 54

In a single sodium-potassium pump cycle, ATP is used with the result that

Answer 54

3 sodium ions leave and 2 potassium ions enter.

Question 55

The type of movement that is specific and requires carrier molecules and energy is

Answer 55

active transport

Question 56

Some prokaryotes attach to other substrates by hairlike outgrowths, which are shorter than flagella. These are called

Answer 56

pili.

Question 57

Which of the following enables a cell to pick up and concentrate a specific type of molecule?

Answer 57

receptor-mediated endocytosis

Question 58

If left untreated, syphilis infections go through four stages. The first stage is a sore calleda chancre. The signs of the second stage are

Answer 58

rash, sore throat, and sores in the mouth

Question 59

Organelles that breakdown hydrogen peroxide into water and oxygen are:

Answer 59

peroxisomes.

Question 60

The part of a membrane protein that extends through the phospholipid bilayer is primarily composed of amino acids that are

Answer 60

non-polar.

Question 61

Small cells function more effectively, because as cells become larger their surface area to volume ratio:

Answer 61

decreases

Question 62

On the outer surface of the plasma membrane there are marker molecules that identify the cell type. Often these molecules are

Answer 62

carbohydrate chains

Question 63

Current classification of prokaryotes is based on

Answer 63

sequencing of proteins, DNA, and RNA.

Question 64

The movement of substances to regions of lower concentration is called

Answer 64

diffusion