Brainscape's Knowledge GenomeTM

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


See full index

H Biology > unit 2 > Flashcards

unit 2 Flashcards

1
Q

Define cell metabolism

A

total set of reactions in a cell

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

What are metabolic pathways (+ other info)

A

series of enzyme catalysed reactions within a cell

  • integrated meaning diff pathways are inter linked
  • may have reversible and irreversible steps
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define anabolic reactions

A

synthesis reactions that build up small molecules into large molecules and require energy

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

Define catabolic reactions

A

degradation reactions that break down large molecules into smaller molecules and release energy

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

How do membranes allow molecules through

A

Protein pore allow or restrict the passage of molecules through the membrane

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

What are protein pumps

A

move molecules across the membrane and require energy to do this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do enzymes in membranes do

A

catalys specific biochemical reactions

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

How can metabloc reactions be controlled

A

by the presence or absence of enzymes

or the regulation of key enzyme activity

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

Define induced fit

A

how the active site of enzyme may change shape to better fit the substrate as the substrate binds

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

Describe enzymes affect on activation energy

A

enzymes lower the activation energy

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

Substrate molecules have a …. affinity for the ……. which means ….

A

high affinity for the active site meaning they bind readily

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

Products have a …. affinity for the …. meaning ….

A

low affinity for the active site meaning they can leave the active site

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

As substrate concentration increases …. but ….

A

the rate of reaction increases but will eventually become constant as it reaches its optimum rate

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

How to change reversible reactions

A

the presence of substrate or removal of product can drive a sequence of reactions in a particular direction

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

What do competitive inhibitors do

A

bind to an active site preventing the substrate from binding

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

How can competitive inhibition be reversed

A

increasing the substrate concentration

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

What do non competitive inhibitors do

A

bind away from the active site which has an effect of changing the shape of the active site preventing the substrate from binding

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

When does feedback inhibition occur

A

this occurs when the end product of a metabolic pathway reaches a critical concentration

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

Define feedback inhibition

A

where the end product inhibits an earlier enzyme in a metabolic pathway which prevents further synthesis of the end product

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

Define respiration

A

the breakdown of respiratory substrates to release energy in the form of ATP

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

Define glycolysis

A

the breakdown of glucose to pyruvate in the cytoplasm

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

What are the two phases of glycolysis

A

the energy investment phase and the and the energy pay off phase

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

What happens in the energy investment phase

A

ATP is required to phosphorylate glucose and intermediates

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

What does phosphorylation in the energy investment phase result in

A

the generation of more ATP in the energy pay off phase

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

What is the net gain of ATP in glycolysis

A

2

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

What is the end product in glycolysis

A

pyruvate

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

What happens in aerobic glycolysis

A

pyruvate is broken down into an acetyl group

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

What does acetyl combing with and form (respiration)

A

combines with coenzyme A to form acetyl coenzyme A

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

Where does the citric acid cycle take place

A

in the matrix of the mitochondria

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

What happens to the acetyl group after it combines with coenzyme A

A

combines with oxaloacetate to form citrate

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

What happens to citrate

A

it is gradually converted back into oxaloacetate in a series of enzyme controlled steps

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

What is produced/released in the citric acid cycle

A

produces ATP and releases carbon dioxide

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

What do dehydrogenase enzymes do

A

they remove hydrogen ions and electrons from intermediates and pass them to the coenzyme NAD to form NADH

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

What happens to hydrogen ions and electrons from NADH

A

passed to the electron transport chain

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

Where is the electron transport chain located

A

the inner mitochondrial membrane

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

What happens when electrons are passed along the electron transport chain

A

they release energy

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

What is the electron transport chain

A

a series of carrier proteins on the inner mitochondrial membrane

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

What does the energy released in the electron transport chain do

A

allows hydrogen ions to be pumped across the inner mitochondrial membrane into the space between the inner and outer mitochondrial membrane

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

How is ATP produced in the electron transport chain

A

the flow of hydrogen ions through the inner membrane portein ATP synthase

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

Describe the role of oxygen in respiration

A

oxygen is the final hydrogen/electron acceptor as it combines with the hydrogen ions and electrons to form water

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

What is fermentation

A

occurs in the cytoplasm at the lack of oxygen

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

Fermentation results in much ….. than aerobic respiration

A

much less ATP production

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

What happens to pyruvate in animal cells

A

it is converted into lactate

this is a reversible reaction

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

What happens to pyruvate in plants and fungi

A

it is converted into ethanol and carbon dioxide

this is an irreversible reaction

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

ATP is used to …… which require energy

A

to transfer energy to processes which require energy

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

What cellular processes require energy

A

Protein synthesis, contraction of muscles, active transport, DNA replication and carbon fixation

47
Q

Metabolic rates can be compared by …..

A

measuring oxygen consumption, carbon dioxide production or heat production

48
Q

Oxygen consumption can be measured using ….

A

an oxygen probe

49
Q

Carbon dioxide can be measured using ….

A

a carbon dioxide probe

50
Q

Heat production can be measured using ….

A

a calorimeter

51
Q

Organisms with high metabolic rates ….

A

require efficient delivery of oxygen to cells

52
Q

Rate birds+mammals, reptiles+amphibians and fish by their metabolic rates (high to low)

A

birds and mammals -> reptiles and amphibians -> fish

53
Q

What circulatory system do birds and mammals have + explain it

A

complete double circulatory system with two atria and two ventricles

54
Q

What circulatory systems do amphibians and most reptiles have + explain it

A

incomplete double circulatory system with two atria and one ventricle

55
Q

What circulatory system do fish have + explain it

A

single circulatory system with one atria and one ventricle

56
Q

Why are complete double circulatory systems the most efficient

A

they enable higher metabolic rates by preventing the mixing oxygenated and deoxygenated blood
+
they also keep blood at high pressures allowing efficient oxygen delivery to cells

57
Q

The metabolic rate of an organism is affected by ….. eg ….

A

abiotic factors eg temperature salinity and pH

58
Q

The internal environment of conformers is dependent on …..

A

the external environment

59
Q

How do conformers tolerate variations in the external environment

A

behavioural responses eg lizards basking in the sun

60
Q

Define conformers abilities

A

low metabolic costs (do not require energy) and can only occupy a narrow range of ecological niches

61
Q

The internal environment of regulators is ….

A

maintained regardless of the external environment

62
Q

Regulators use metabolism to ….

A

control their internal environment eg water balance, temperature, blood sugar

63
Q

Define homeostasis

A

the use of physiological mechanisms to maintain internal body conditions at optimum levels

64
Q

Define regulators abilities

A

they expend energy (eg to migrate and avoid adverse conditions) and occupy a wider range of ecological niches

65
Q

Define thermoregulation

A

the maintenance of a constant internal temperature

66
Q

What is the temperature monitoring centre in the body

A

the hypothalamus

67
Q

How does the hypothalamus recieve and send messages

A

recieves messages through nerve impulses from thermo-receptors in the skin and sends messages through nerve impulses to effectors

68
Q

Define negative feedback control

A

uses corrective responses to revers changes in internal tempereature to return temperature to normal //or// a change in a factor triggers a mechanism which results in that factor returning to normal level (set point)

69
Q

What are the 3 human responses to increase in body temperature/overheating

A

+ sweating - body heat is used to evaporate water in sweat thereby cooling the skin
+ vasodilation - increased blood flow to the skin increases heat loss by radiation
+ reduction in metabolic rate - to reduce heat production

70
Q

What are the 4 human responses to decrease in body temperature/overcooling

A

+ shivering - rapid involuntary muscle contraction generates heat
+ vasoconstriction - decreased blood flow to the skin decreases heat loss by radiation
+ contraction of hair erector muscles - traps a layer of insulating air
+ increase in metabolic rate - to produce more heat

71
Q

Why is maintenance of body temperature required + what does it ensure

A

for optimal enzyme activity

ensures high diffusion rates required to maintain metabolism

72
Q

Regulators are unable to maintain their internal environment when ….

A

when the external environment varies beyond tolerable limits for normal metabolic activity

73
Q

Define dormancy

A

part of a lifecycle allowing survival during conditions when the energy costs of metabolic activity would be too high

74
Q

During dormancy the metabolic rate …..

A

is reduced to save energy

75
Q

Define predictive dormancy

A

occurs before the onset of adverse conditions

76
Q

Define consequential dormancy

A

occurs after the onset of adverse conditions

77
Q

How do some animals survive low winter temperatures

A

hibernation

78
Q

How do some organisms survive high temperatures/drought

A

aestivation

79
Q

Define daily torpor

A

when some animals with high metabolic rates can temporarily reduce their metabolic rate eg hummingbirds

80
Q

Why do animals migrate/what is migration

A

migration involves relocating to an area with more suitable environmental conditions
uses energy to avoid adverse conditions

81
Q

What is innate behaviour

A

behaviour that is inherited (migration can be this)

82
Q

What is learned behaviour

A

behaviour that parents teach/is developed as a result of experience (migration can be this)

83
Q

How can migration be tracked

A

radio/satellite tracking, marking, radar and sonar

84
Q

Micro-organisms include ….

A

archea, bacteria and some eukaryotes

85
Q

Micro-organisms use …. and produce ….

A

microorganisms use a wide variety of substrates for metabolism and produce a range of products from their metabolic pathways

86
Q

Describe micro-organisms growth media

A

contains raw materials for biosynthesis and an energy source

87
Q

Some microorganisms produce their own …. and some require ….

A

produce their own complex molecules for biosynthesis (e.g amino acids vitamins and fatty acids) and some require complex molecules in the growth medium

88
Q

Where is the energy source for a microorganism derived from

A

from a chemical substrate or from light in photosynthetic micro organisms

89
Q

How is a fermenter used in the culture of micro organisms

A
  • provides optimum conditions through control of temp, oxygen level and pH
  • provides sterile conditions to reduce competition for nutrients with unwanted microorganisms and reduces the risk of spoilage of the product
90
Q

Examples of products produced in fermenters

A

antibiotics, enzymes, vaccines

91
Q

What are the four phases of frowth and changes in culture conditions graph

A

lag
log
stationary
death

92
Q

Explain the lag phase of the graph

A

enzymes are induced to metabolise substrates + cells adjust to conditions

93
Q

Explain the log phase of the graph

A

rapid growth of micro-organisms due to plentiful nutrients / cells grow and multiply at maximum rate

94
Q

Explain the stationary phase of the graph

A

due to nutrient depletion and toxic metabolites begin to accumulate / number of cells dying is equal to number of cells produced

95
Q

Explain the death phase of the graph

A

due to toxic metabolites accumulation and lack of nutrients / number of cells dying exceeds number being produced
+ only viable cell count shows in this phase

96
Q

Define secondary metabolites

A

produced in the stationary phase and may confer an ecological advantage in the wild by allowing the micro-organism to outcompete other species e.g antibiotics

97
Q

Define viable cell count

A

only the living cells

98
Q

Define total cell count

A

both living and dead cells

99
Q

What does mutagenesis of recombinant DNA technology do?

A

improve wild strains of micro organisms

100
Q

Define mutagenesis

A

the creation of mutations and can be achieved using mutagenic agents e.g. uv light, x-rays and gamma rays, mustard gas

101
Q

Exposure of microorganisms to mutagenic agents results in …

A

mutations which may produce an improved strain of micro organism e.g. give an increased yield of product

102
Q

What is recombinant dna technology

A

describes taking a gene from an organism and transferring it into a micro organism to enable the micro organism to produce plant or animal proteins

103
Q

What is a vector (DNA)

A

a DNA molecule used to carry foreign genetic material into another cell e.g. plasmids and artificial chromosomes

104
Q

When are artificial chromosomes preferable over plasmids as vectors

A

when larger fragments of DNA are required to be inserted

105
Q

What are restriction endonuclease enzymes used for

A

recognising specific nucleotide base sequences and cutting specific genes out at those sequences leaving sticky ends
+
recognising specific nucleotide base sequences and cutting open plasmids at those sequences

106
Q

How are complementary sticky ends produced

A

when the same restriction endonuclease is used to cut open the plasmid and cut out the gene from the chromosome

107
Q

How are complementary DNA sequences sealed into place

A

DNA ligase enzymes

108
Q

What do recombinant plasmids and artificial chromosomes contain

A

restriction sites, regulatory sequences, an origin of replication and selectable markers

109
Q

Restriction sites contain ….

A

target sequences of DNA where specific endonucleases cut

110
Q

What do regulatory sequences do

A

controls gene expression

111
Q

What does the origin of replication do

A

allows self replication of the plasmid/artificial chromosome

112
Q

What do selectable marker genes do

A

ensure that only microorganisms that have taken up the vector grow in the presence of the selective agent eg antibiotic resistance genes

113
Q

Genes may be introduced to a genetically engineered micro-organisms genome to ….

A

to prevent its survival in the external environment as a safety mechanism

114
Q

Recombinant yeast cells may be used instead of bacteria because ….

A

bacteria may be unable to produce an active form of protein due to an inability to correctly fold polypeptides

H Biology (3 decks)

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