Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

biology. unit 3 > molecular biology > Flashcards

molecular biology Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

macromolecules

A

proteins
carbohydrates
lipids
nucleic acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

metabolism

A

is the web of all the enzyme-catalysed reactions in a cell or organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

anabolism

A

the synthesis of molecules from small to larger molecules, condensation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

catabolism

A

the breaking down of molecules, hydrolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

organic compounds

A

carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

carbon properties

A 
can form 4 bonds 
can bond to functional bonds
can form covalent bonds
can for double and triple bonds 
can form chains or rings
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

carbohydrates form from

A

CHO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

proteins form from

A

CHON

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

lipids form from

A

CHO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

nucleic acids

A

CHONP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

monomer of carbohydrates

A

monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

monomer of proteins

A

amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

monomer of lipids

A

fatty acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

monomer of nucleic acid

A

nucleotide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

vitalism

A

a doctrine that dictated that organic molecules could only be synthesised by living systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

falsification of vitalism

A

synthesis of urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

water

A

H2O

two hydrogen atoms covalently bonded to oxygen atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

properties of water

A

cohesion
adhesion
solvent properties
thermal properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

polarity of water

A

water is polar due to the slight difference in electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

heat properties of water

A

Water has the capacity to absorb significant amounts of heat before changing state

This is due to the extensive hydrogen bonding between water molecules – the H-bonds need to be broken before a change in state can occur and this requires the absorption of energy (heat)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

difference in water and methane

A 
water:
polar 
intermolecular hydrogen bonds
higher boiling and melting point
higher specific heat capacity
higher heat vaporization
higher heat of vaporization 
higher heat of fusion

methane:
non polar
weak dispersion forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

sweat

A

use of water as a coolant as
The change of water from liquid to vapour (evaporation) requires an input of energy
This energy comes from the surface of the skin when it is hot, therefore when the sweat evaporates the skin is cooled
Because water has a high specific heat capacity, it absorbs a lot of thermal energy before it evaporates
Thus water functions as a highly effective coolant, making it the principal component of sweat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

cohesion

A

ability of the same molecule to stick together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

adhesion

A

ability different molecules to stick together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

surface tension

A

cohesion
The hydrogen bonding between water molecules allows the liquid to resist low levels of external force (surface tension)
The high surface tension of water makes it sufficiently dense for certain smaller organisms to move along its surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

capillary action

A

adhesion properties allows water to defy the movement of gravity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

solvent properties

give an example

A

water can dissolve any molecule with ions and electronegative atoms (polarity)
for example: NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

polysaccharides

A

multiple monosaccharides joined together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

disaccharides

A

2 monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what are carbohydrates

A

sugars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

monosaccharides

A

glucose
galactose
fructose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

disaccharide

A

sucrose
maltose
lactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

polysaccharides

A

glycogen
cellulose
starch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

cellulose

A

found in cell walls of plants made of B-glucose (1-4 arrangement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

starch

A

energy storage polysaccharide found in plants
It is composed of α-glucose subunits (bound in a 1-4 arrangement) and exists in one of two forms – amylose or amylopectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

amylose

A

is a linear (helical) molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

amylopectin

A

is branched (contains additional 1-6 linkages)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

glycogen

A

energy storage polysaccharide formed in the liver in animals

It is composed of α-glucose subunits linked together by both 1-4 linkages and 1-6 linkages (branching)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

types of fatty acids

A

saturated
monounsaturated
polyunsaturated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

unsaturated

A

contains 1 or more double bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

types of unsaturated fats

A

cis: bent, hydrogen on the same side
trans: straight, hydrogen on different sides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are triglycerides

A

polymer of lipids, formed by condensation of three fatty acids and 1 glycerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

function of triglycerides

A

store long term energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

bad fats

A

saturated and trans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

regulating blood cholesterol level

A

Low density lipoproteins (LDL) carry cholesterol from the liver to the rest of the body
High density lipoproteins (HDL) scavenge excess cholesterol and carry it back to the liver for disposal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

types of fats affect cholesterol

A

saturated and trans increase LDL, therefore high cholesterol
cis increase HDL, lowering cholesterol levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

risks of cholesterol

A

hardening and narrowing of arteries
The accumulation of fat within the arterial walls lead to the development of plaques which restrict blood flow

If coronary arteries become blocked, coronary heart disease (CHD) will result – this includes heart attacks and strokes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

lipid health claims

A

Diets rich in saturated fats and trans fats increase the risk of CHD
Diets rich in monounsaturated and polyunsaturated (cis) fats decrease the risk of CHD

49
Q

difference in carbohydrates and lipids

A 
both store energy, however carbohydrates is short term energy storage meanwhile lipids are used for long term energy storage.
carbohydrates:
store half the ATP
stronger effect on osmotic pressure
water soluble
readily digested
lipids: 
stores twice as much ATP
less effect on osmotic pressure
hydrophilic 
less easily digested
50
Q

body mass index

A

mass in kg/ (height in m)^2

51
Q

types of lipids

A 
steroids
triglycerides 
phospholipids 
waxes
glycolipids
52
Q

amino acids components

A

An amine group (NH2)
A carboxylic acid group (COOH)
A hydrogen atom (H)
A variable side chain (R)

53
Q

polypeptides

A

multiple amino acids joined together

54
Q

denaturation

A

a structural change in a protein that results in the loss (usually permanent) of its biological properties, unfolded protein

55
Q

what causes the denaturation of protein

A

pH- Changing the pH will alter the charge of the protein, which in turn will alter protein solubility and overall shape
temperature-High levels of thermal energy may disrupt the hydrogen bonds that hold the protein together

56
Q

gene sequencing is converted into a polypeptide by:

A

transcription-making an mRNA transcript based on a DNA template (occurs within the nucleus)
translation-using the instructions of the mRNA transcript to link amino acids together (occurs at the ribosome)

57
Q

what is a proteome

A

all of the proteins produced by a tissue, cell, or an organism.

58
Q

what are the functions of protein?

A 
catalysis
muscle contraction
membrane transport
cell to cell communication
cell adhesion
transport of nutrients and gas
hormones
receptors
packing of DNA
Immunity
blood clotting
tonsil strengthening
cytoskeletons
59
Q

what is an enzyme?

A

a globular protein which acts as a biological catalyst by speeding up the rate of a chemical reaction

60
Q

what is the active site?

A

the region on the surface of the enzyme which binds to the substrate molecule

61
Q

The rate of enzyme catalysis can be increased by improving the frequency of collisions via:

A

Increasing the molecular motion of the particles (thermal energy can be introduced to increase kinetic energy)
Increasing the concentration of particles (either substrate or enzyme concentrations)

62
Q

enzyme activity

A
  1. substrate binds to active site of the enzyme
  2. while the substrates are bound to the active site they change into chemical reactions.
  3. the products separate from the active site, leaving it vacant for other substrates to bind again
63
Q

factors that affect enzymatic activities:

A

temperature
pH
substrate concentration

64
Q

how does temperature affect enzymatic activity

A
  • Low temperatures result in insufficient thermal energy for the activation of an enzyme-catalysed reaction to proceed
    Increasing the temperature will increase the speed and motion of both enzyme and substrate, resulting in higher enzyme activity
    Higher temperatures THAN OPTIMAL TEMPERATURE will cause enzyme stability to decrease, as the thermal energy disrupts the enzyme’s hydrogen bonds
    This causes the enzyme (particularly the active site) to lose its shape, resulting in the loss of activity (denaturation)
65
Q

how does pH affect enzymatic activity

A

Changing the pH will alter the charge of the enzyme, which in turn will alter protein solubility and overall shape
Changing the shape or charge of the active site will diminish its ability to bind the substrate, abrogating enzyme function

66
Q

how does substrate concentration affect enzymatic activity

A

Increasing substrate concentration will increase the activity of a corresponding enzyme
More substrates mean there is an increased chance of enzyme and substrate colliding and reacting within a given period
After a certain point, the rate of activity will cease to rise regardless of any further increases in substrate levels
This is because the environment is saturated with substrate and all enzymes are bound and reacting (Vmax)

67
Q

measuring enzyme activity

A

gas production
digestion of a solid
digestion of a liquid
color change

68
Q

immobilised enzymes are utilised in a wide variety of industrial practices

A 
Biofuels
Medicine 
Biotechnology
Food production
Textiles
Paper
69
Q

lactose

A

a disaccharide that is produced in lactating mammals as an energy source for newborns

70
Q

lactose intolerance

A

they do not contain lactase. Without lactase, lactose will pass intact into the large intestine, where it is broken down by probiotic bacteria, As part of the bacterial fermentation process, large amounts of gas are produced
This leads to the various ailments associated with lactose intolerance – including abdominal bloating, cramps and flatulence

71
Q

nucleic acids

A

the genetic material of the cell and are composed of recurring monomeric units called nucleotides

72
Q

Each nucleotide is comprised of three principal components:

A 
5-carbon pentose sugar (pentagon)
Phosphate group (circle)
Nitrogenous base (rectangle)
73
Q

two types of nucleic acids present in our cells

A

DNA AND RNA

74
Q

difference between DNA and RNA

A 
DNA:
deoxyribose
ATGC
double stranded forming a double helix
RNA:
ribose
AUGC
one stranded
carries a message
75
Q

what are the three types of RNA

A

mRNA, rRNA, tRNA

76
Q

DNA structure

A

A-T
G-C
strands describes as antiparallel
double helix, twists at intervals every 34 angstrom
orientation: Nitrogenous bases are closely packed together on the inside and phosphates form an outer backbone

77
Q

DNA replication is a:

A

semiconservative process:
One strand will be from the original template molecule
One strand will be newly synthesised

78
Q

two key enzyme of DNA replication

A

helicase- unzips or unwinds the double strands

DNA polymerase- synthesizes a new strand

79
Q

HL:

complex system of enzymes for the replication of DNA

A

helicase
primase-DNA primase generates a short RNA primer (~10–15 nucleotides) on each of the template strands
polymerase 1- Free nucleotides align opposite their complementary base partners (A = T ; G = C)
DNA pol III attaches to the 3’-end of the primer and covalently joins the free nucleotides together in a 5’ → 3’ direction
As DNA strands are antiparallel, DNA pol III moves in opposite directions on the two strands
On the leading strand, DNA pol III is moving towards the replication fork and can synthesise continuously
On the lagging strand, DNA pol III is moving away from the replication fork and synthesises in pieces (Okazaki fragments)
and 3- As the lagging strand is synthesised in a series of short fragments, it has multiple RNA primers along its length
DNA pol I removes the RNA primers from the lagging strand and replaces them with DNA nucleotides
ligase-DNA ligase joins the Okazaki fragments together to form a continuous strand
gyrase-DNA gyrase reduces the torsional strain created by the unwinding of DNA by helicase
Single Stranded Binding (SSB) Proteins-SSB proteins bind to the DNA strands after they have been separated and prevent the strands from re-annealing
These proteins also help to prevent the single stranded DNA from being digested by nucleases

80
Q

leading versus lagging strand

A

On the leading strand, DNA polymerase is moving towards the replication fork and so can copy continuously
On the lagging strand, DNA polymerase is moving away from the replication fork, meaning copying is discontinuous

81
Q

Okazaki fragments

A

the short fragments copied on the lagging strand

82
Q

non-coding DNA

A

genes that are inactivated

83
Q

types of non-coding dna

A

satellite DNA, telomeres, introns, ncRNA genes and gene regulatory sequences

84
Q

nucleosome

A

the DNA is packaged with histone proteins to create a compacted structure

85
Q

function of nucleosomes

A

Nucleosomes help to supercoil the DNA, resulting in a greatly compacted structure that allows for more efficient storage
Supercoiling helps to protect the DNA from damage and also allows chromosomes to be mobile during mitosis and meiosis

86
Q

what does a nucleosome consist of

A

A nucleosome consists of a molecule of DNA wrapped around a core of eight histone proteins (an octamer)

87
Q

telomerase

A

Telomeres can be lengthened by the enzyme telomerase, allowing for continued cell division past the Hayflick limit
Permanent activation of telomerase can cause cells to become immortal and leads to cancer (uncontrolled cell division)

88
Q

transcription

A

the process by which an RNA sequence is produced from a DNA template

89
Q

HL three main parts of transcription

A

promoter=The promoter functions as a binding site for RNA polymerase (the enzyme responsible for transcription)
coding sequence -After RNA polymerase has bound to the promoter, it causes the DNA strands to unwind and separate
The region of DNA that is transcribed by RNA polymerase is called the coding sequence

terminator - RNA polymerase will continue to transcribe the DNA until it reaches a terminator sequence

90
Q

transcription process

A

RNA polymerase separates the DNA strands and synthesises a complementary RNA copy from one of the DNA strands
When the DNA strands are separated, ribonucleoside triphosphates align opposite their exposed complementary base partner
RNA polymerase removes the additional phosphate groups and uses the energy from this cleavage to covalently join the nucleotide to the growing sequence
Once the RNA sequence has been synthesised, RNA polymerase detaches from the DNA molecule and the double helix reforms, transcription happens from 5’–> 3’

91
Q

three post-transcriptional events

A

capping
Polyadenylation
Splicing

92
Q

capping

A

Capping involves the addition of a methyl group to the 5’-end of the transcribed RNA
The methylated cap provides protection against degradation by exonucleases

93
Q

Polyadenylation

A

Polyadenylation describes the addition of a long chain of adenine nucleotides (a poly-A tail) to the 3’-end of the transcript
The poly-A tail improves the stability of the RNA transcript and facilitates its export from the nucleus

94
Q

Splicing

A

removal of introns

95
Q

alternative splicing

A

removal of exons

96
Q

SL: genetic codes

A

the set of rules by which information encoded within mRNA sequences is converted into amino acid sequences (polypeptides) by living cells

97
Q

codons

A

The mRNA sequence is read by the ribosome in triplets of bases

98
Q

HL: Regulatory proteins bind to DNA sequences outside of the promoter and interact with the transcription factors

A

activator proteins- increases rate of transcription

silencer protein- decreases rate of transcription

99
Q

control elements

A

The DNA sequences that regulatory proteins bind to

100
Q

types of chromatin

A

heterochromatin

euchromatin

101
Q

heterochromatin

A

When DNA is supercoiled and not accessible for transcription

102
Q

euchromatin

A

When the DNA is loosely packed and therefore accessible to the transcription machinery

103
Q

epigenetic

A

the study of changes in phenotype as a result of variations in gene expression levels

104
Q

translation

A

the process of protein synthesis in which the genetic information encoded in mRNA is translated into a sequence of amino acids on a polypeptide chain

105
Q

ribosomes

A

Ribosomes are made of protein (for stability) and ribosomal RNA (for catalytic activity)

106
Q

what do ribosomes consist of

A

The small subunit contains an mRNA binding site

The large subunit contains three tRNA binding sites – an aminoacyl (A) site, a peptidyl (P) site and an exit (E

107
Q

steps of translation

A

initiation
elongation
termination

108
Q

translocation

A

when the peptide chain moves to p site and theater one is decayed to the E site

109
Q

polysome

A

a group of two or more ribosomes translating an mRNA sequence simultaneously

110
Q

cell respiration

A

the controlled release of energy from organic compounds to produce ATP

111
Q

types of cell respiration

A

Anaerobic respiration involves the partial breakdown of glucose in the cytosol for a small yield of ATP
Aerobic respiration utilises oxygen to completely break down glucose in the mitochondria for a larger ATP yield

112
Q

what is ATP (adenosine triphosphate)

A

a high energy molecule that functions as an immediate source of power for cell processes

113
Q

glycolysis

A

Glycolysis breaks down glucose (6-C) into two molecules of pyruvate (3C), and also produces:

    • Hydrogen carriers (NADH) from an oxidised precursor (NAD+)
    • A small yield of ATP (net gain of 2 molecules)
114
Q

the pyruvate is converted into

A

in animals–> lactic acid

plants–>ethanol and carbon dioxide

115
Q

what energy storage will undergo anaerobic respiration

A

carbohydrates

116
Q

where does Aerobic cell respiration take place and what does it require

A

requires the presence of oxygen and takes place within the mitochondrion

117
Q

what does aerobic respiration consist of

A

consists of the link reaction, citric acid cycle (or Krebs cycle) and the electron transport chain

118
Q

respirometer

A

a device that determines an organism’s respiration rate by measuring the rate of exchange of O2 and CO2

119
Q

factors that affect the rate of respiration

A

temperature, hydration, light (plants), age and activity levels

biology. unit 3 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions