bio exam 2

studied byStudied by 1 person
0.0(0)
get a hint
hint

most of a cells enzymes are

1 / 167

Tags and Description

Biology

168 Terms

1

most of a cells enzymes are

proteins

New cards
2

in the plasma membrane, the phospholipid heads

are both hydrophilic and face outward toward the aqueous solution on both sides of the membrane

New cards
3

aquaporin's

allow water to cross the plasma membrane via facilitated diffusion

New cards
4

kinetic energy differs from chemical energy in that

kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules

New cards
5

you are told that the cells on a microscope slide are plant, animal, or bacterial. you look at them through a microscope and see cell walls and membrane bound organelles. you conclude correctly that the cells

are plant cells

New cards
6

anything that prevents atp formation will most likely

result in cell death

New cards
7

which metabolic pathway is common to aerobic and anaerobic metabolism

glycolysis

New cards
8

in fermentation ___________ is _____________

nadh; oxidized

New cards
9

when a cell uses chemical energy to perform work, it uses the energy released from a(n) ____________ reaction to drive a(n) ___________ reaction

exergonic; endergonic

New cards
10

what is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?

rough er, golgi, vesicles that fuse with plasma membrane

New cards
11

the tertiary structure of a protein is the

unique three-dimensional shape of the fully folded polypeptide

New cards
12

which organelle or structure is absent in plant cells

centrosomes

New cards
13

according to the fluid mosaic model of membrane structure, proteins of the membrane are mostly

embedded in a lipid bilayer

New cards
14

which cell would be best for studying lysosomes

phagocytic white blood cell

New cards
15

which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly

CO2

New cards
16

which of the following is a major cause of the size limits for certain types of cells

the need for a surface area of sufficient area to support the cells metabolic needs

New cards
17

how many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long

10

New cards
18

when chemical, transport, or mechanical work is done by an organism, what happens to the heat generated

it is lost to the environment

New cards
19

the bonding of two amino acid molecules to form a larger molecule requires which of the following

removal of a water molecule

New cards
20

which level of protein structure do the helix and the beta pleated sheet represent

secondary

New cards
21

which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid at lower temperature

the double bonds form kinks in the fatty acid tails, preventing adjacent lipids from packing tightly

New cards
22

which of the following is true of both starch and cellulose

they are both polymers of glucose

New cards
23

which of these experimental treatments would increase the rate of sucrose transport into the cell

decreasing extracellular pH

New cards
24

the r group or side chain of the amino acid serine is -CH2-OH. the r group or side chain of amino acid leucine is -CH2-CH-(CH3)2. where would you expect to find these amino acids in a globular protein in aqueous solution

leucine would be in the interior, and serine would be on the exterior of the globular protein

New cards
25

in receptor mediated endocytosis, receptor molecules initially project to the outside of the cell. where do they end up after endocytosis

on the inside surface of the vesicle

New cards
26

which or the following statements correctly describes the normal tonicity conditions for typical plant and animal cells

the animal cells is in an isotonic solution, and the plant cell is in a hypotonic solution

New cards
27

how might an amino acid change at a site distant from the active site of the enzyme alter the enzymes substrate specifically

by changing the shape of the protein

New cards
28

which of the following correctly lists the order in which cellular components will be found in the pellet when homogenized cells are treated with increasingly rapid spins in a centrifuge

nucleus, mitochondria, ribosomes

New cards
29

enzymes that break down dan catalyze the hydrolysis of the covalent bonds that join nucleotides together. what would happen to dns molecules treated with these enzymes

the phosphodiester linkages of the polynucleotide backbone would be broken

New cards
30

which of the following statements about the 5' end of a polynucleotide strand of dna is correct

the 5' end has a phosphate group attached to the number 5 carbon of carbon deoxyribose

New cards
31

if cells are grown in a medium containing radioactive 32P labeled phosphate, which of these molecules will be labeled

both phospholipids and nucleic acids

New cards
32

the element present in all organic molecules is

carbon

New cards
33

which of the following is not a monomer/polymer pairing

triglyceride/phospholipid bilayer

New cards
34

which of the following is an example of potential rather than kinetic energy

a molecule of glucose

New cards
35

an animal cell lacking oligosaccharides on the external surface of its plasma membrane would likely be impaired in which function

cell-cell recognition

New cards
36

what is the chemical reaction mechanism by which cells make polymers from monomers

dehydration reactions

New cards
37

the golgi apparatus has a polarity or sidedness to its structure and function. which of the following statements correctly describes this polarity

proteins and lipids in the membrane of the golgi may be sorted and modified as they move from one side of the golgi to the other

New cards
38

a biologist wants specifically to examine the surface of different types of cells in kidney tubules of small mammals. the cells in question can be distinguished by external shape, size, and 3-D characteristics. which of the following would be the optimum method for her study

scanning electron microscopy

New cards
39

protein kinases are enzymes that catalyze phosphorylation of target proteins at specific sites, whereas protein phosphates catalyze removal of phosphate(s) from phosphorylated proteins. phosphorylation and dephospho rylation can function as an on-off switch for a proteins activity, most likely through

the change in a proteins charge leading to a conformational change

New cards
40

which of the following is true for all exergonic reactions

the reactions proceeds with a net release of free energy

New cards
41

a dietary calorie equals 1 kilocalorie. which of the following statements correctly defines 1 kilocalorie

1000 calories, or the amount of heat required to raise the temperature of 1 kg by 1C

New cards
42

dehydration reactions are used in forming which of the following compounds

triacylglycerides, polysaccharides, and proteins

New cards
43

all of the following are part of a prokaryotic cell except

a cell wall

New cards
44

what is another name for a condensation reaction

dehydration

New cards
45

what is the name of the process during which a bond between two monomers is broken

hydrolysis

New cards
46

nucleic acid polymers are made up of ____________ monomers

nucleotide

New cards
47

carbohydrate polymers are made up of _______________ monomers

simple sugar

New cards
48

protein polymers are made up of _____________ monomers

amino acid

New cards
49

which element is closely associated with the field of organic chemistry

carbon

New cards
50

what does the term amino acid signify about the structure of the molecule

it consists of an amino group and a carboxyl group

New cards
51

polymers that contain sugars ...

may store hereditary information, may store energy, and may protect cells

New cards
52

what one characteristic is shared by sucrose and maltose

they are disaccharides

New cards
53

glycogen is _____________

a polysaccharide found in animals

New cards
54

glucose + glucose --> _________ by _________

maltose + water ; dehydration synthesis

New cards
55

which of these is a source of lactose

milk

New cards
56

which of these is a polysaccharides

cellulose

New cards
57

________ is the most abundant organic compounds on earth

cellulose

New cards
58

lipids are diverse compounds that are grouped together because they are _________

hydrophobic

New cards
59

a fat molecule is composed of two typer of smaller molecules: ___________ and fatty acids

glycerol

New cards
60

a fatty acid consists of a ________________ and a long hydrocarbon chain

carboxyl group

New cards
61

________________ have one or more double bonds in their hydrocarbon chains and are usually found in vegetable oils

unsaturated fatty acids

New cards
62

the hydrocarbon chains of _______________ are not kinked, and thus pack closely together, making animal fats solid at room temperature

saturated fatty acids

New cards
63

____________ are a major component of cell membranes. they form a bilayer with their hydrophobic tails mingling together and their hydrophilic heads facing the watery environment on both sides of the membrane

phospholipids

New cards
64

________ are lipids with a structure consisting of four fused rings. many sex hormones are made from this type of lipid

steroids

New cards
65

which of these is not a lipid

RNA

New cards
66

which of these is rich in unsaturated fats

olive oil

New cards
67

a function of cholesterol that does not harm health is its role _______

as a component of animal cell membranes

New cards
68

the lipids that form the main structural component of cell membranes are _______

phospholipids

New cards
69

some athletes use anabolic steroids to build their body mass. why is this considered a problematic practice, especially in adolescents

anabolic steroids can prevent bone growth

New cards
70

defensive proteins are manufactured by the _______ system

immune

New cards
71

your body contains thousands of different types of proteins, each with a specific function. a proteins function is largely determined by its ___________

shape

New cards
72

the primary structure of a protein is like the arrangement of beads on a string. in this analogy, the beads are _________

amino acids

New cards
73

a proteins alpha helices and beta sheets form their shapes at the _______ level of protein structure

secondary

New cards
74

what happens to the shape and function of a protein if one of the amino acids is replaced with a different type of amino acid

it depends on the role of the amino acid that is altered. one amino acid might be replaced with no measurable effect on the proteins function; replacing another might cause a total loss of function

New cards
75

large proteins, like dna polymerase and hemoglobin, are often composed of several polypeptides that are linked together. the _______ level of protein structure describes how the polypeptides are joined to create a larger complex

fourth

New cards
76

which of these functional groups is found in all amino acids

-NH2

New cards
77

proteins are polymers of ________

amino acids

New cards
78

what type of bond joins the monomers in a proteins primary structure

peptide

New cards
79

the secondary structure of a protein results from __________

hydrogen bonds

New cards
80

tertiary structure is not directly dependent on __________

peptide bonds

New cards
81

which of the following would be affected when a protein is denatured

tertiary structure

New cards
82

if a dna double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain

75

New cards
83

the two strands of a dna double helix are held together by ________ that form between pairs of nitrogenous bases

hydrogen bonds

New cards
84

a nucleotide is composed of a(n) _________

phosphate group, a nitrogen-containing base, and a five-carbon sugar

New cards
85

nucleic acids are polymers of _________

nucleotides

New cards
86

the monomers of nucleic acids consist of phosphate group, a five carbon sugar, and a _________________

nitrogenous base

New cards
87

________ provides directions for its own replication. it also directs cell activities by providing instructions for building proteins

dna

New cards
88

a gene provides the directions to build a molecule of ________; the genetic instructions it carries are then translated into the amino acid sequence

rna

New cards
89

a polynucleotide has a repeating ___________ backbone

sugar-phosphate

New cards
90

the structure of dna is a __________, held together by the complementary base-pairing of cytosine with guanine, and adenine with thymine

double helix

New cards
91

ran usually consists of a single _______ strand

polynucleotide

New cards
92

which of the following statements regarding lactose tolerance is true

lactose tolerance has evolved independently in multiple different human population

New cards
93

________ are surface appendages that allow a bacterium to stick to a surface

fimbriae

New cards
94

what is the function of bacterium capsule

protection

New cards
95

where is a bacterial cells dna found

nucleoid region

New cards
96

in a bacterium, where are proteins synthesized

ribosomes

New cards
97

what name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell

cell wall

New cards
98

the ________ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell

plasma membrane

New cards
99

which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell

mitochondrion

New cards
100

the plant cell wall

is a protective structure made of cellulose fibrils

New cards

Explore top notes

note Note
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 30 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 22 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 20369 people
Updated ... ago
4.8 Stars(232)
note Note
studied byStudied by 28 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 31832 people
Updated ... ago
4.6 Stars(63)

Explore top flashcards

flashcards Flashcard58 terms
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard54 terms
studied byStudied by 36 people
Updated ... ago
5.0 Stars(2)
flashcards Flashcard52 terms
studied byStudied by 63 people
Updated ... ago
5.0 Stars(2)
flashcards Flashcard101 terms
studied byStudied by 3 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard114 terms
studied byStudied by 23 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard29 terms
studied byStudied by 4 people
Updated ... ago
5.0 Stars(2)
flashcards Flashcard84 terms
studied byStudied by 32 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard111 terms
studied byStudied by 11 people
Updated ... ago
5.0 Stars(1)