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Biology: Unit 2 > Biology Unit 2 > Flashcards

Biology Unit 2 Flashcards

1
Q

What is a metabolic pathway?

A

a metabolic pathway is an integrated series of enzyme-controlled reactions.

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2
Q

what is the term metabolic used to describe?

A

it’s used to describe all of the reactions taking place within a cell

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3
Q

what are the 2 types of metabolic reaction?

A

anabolic reactions ( build-up) and catabolic reactions (break down)

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4
Q

what are anabolic pathways?

A

anabolic pathways are a set of biosynthetic reactions inside a cell that build complex molecules from simple building blocks. these reactions require energy

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5
Q

what is an example of an anabolic pathway?

A

protein synthesis is an example of an anabolic pathway as amino acids are built into protein.

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6
Q

what are catabolic pathways?

A

catabolic pathways are a set of reactions inside a cell that breaks complex molecules into simple building blocks. These reactions release energy

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7
Q

what is an example of a catabolic pathways

A

aerobic respiration is an example of a catabolic pathway as glucose and oxygen are broken down into co2 and water

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8
Q

How are the 2 metabolic pathways closely linked?

A

the energy generated by aerobic respiration (catabolic) is used for protein synthesis (anabolic)

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9
Q

what are the different ways in which metabolic pathway reactions go? (3)

A
  • be reversible
  • be irreversible
  • use alternative routes
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10
Q

what is an example of a reversible reaction?

A

fermentation in animals, oxygen is supplied to the cell, lactate can be converted back to pyruvate.

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11
Q

what is an example of an irreversible reaction?

A

fermentation in plant and yeast, ethanol and co2 cannot be converted back into pyruvate.

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12
Q

what is the importance of membranes? (4)

A

the cell membrane controls the flow of materials into and out of the cell. they also form the surfaces and boundaries of areas where metabolic reactions can occur. Mitochondria and chloroplast are membrane-bound organelles. They form compartments that keep metabolites close together or separated.

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13
Q

what is the characteristic structure of the mitochondria?(4)

A

the mitochondria have a double membrane(inner and outer).
the inner membrane is folded to localise metabolic activity.
-certain sites are responsible for certain chemical reactions
-metabolites are kept close to the enzymes that are required for the reactions to proceed.

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14
Q

what is the characteristic structure of the chloroplast?

A

in chloroplasts, the enzymes needed for making ATP are bound together on flattened sacs containing chlorophyll.
The Calvin cycle occurs in the fluid outside the sacs where the enzymes for the cycle are found.

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15
Q

what are the advantages of having compartmentalised membranes?

A

small compartments in the membrane allow a high surface to volume ratio which allows high concentrations of the substrate inside. This leads to a high reaction rate.

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16
Q

what are the molecules membrane is made up of?

A

proteins and phospholipids

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17
Q

what are the forms of protein embedded in the cell membrane?

A

pores, pumps and enzymes

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18
Q

function of pores?

A

large molecules depend on transport proteins which contain pores to allow them to move across the membrane. the channel allow diffusion of specific substances across the membrane

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19
Q

function of pumps?

A

act as carrier molecules that transfer specific ions across the membrane. Moving across the concentration gradient is active transport and requires ATP.

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20
Q

function of enzymes?

A

speed up the rate of biochemical reactions in the cell. i.e enzymes control the rate of metabolic pathways.

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21
Q

what is activation energy?

A

the energy required to initially break the bonds in the reactants to form an unstable compound.

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22
Q

what does adding enzyme to a reaction do to the activation energy?

A

it lowers the activation energy needed for the reaction to proceed.-meaning biochemical reactions are able to speed up rapidly and at relatively low temp. (body temp.)

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23
Q

why is induced fit useful for?

A
  • ensuring the active site comes into close contact with the substrate molecules increasing the chance of a reaction taking place
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24
Q

what is the affinity of a molecule?

A

it’s the tendency for it to bind to an enzyme

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25
Q

whats the intensity of affinity of a substrate to its active site?

A

substrates have a high affinity for the active site

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26
Q

whats the intensity of affinity of a product after a reaction for the active site?

A

after a reaction. the products have a lower affinity for the active site so they separate.

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27
Q

what is an inhibitor?

A

an inhibitor is a substance that decreases the rate of enzyme controlled reaction.

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28
Q

what are the 3 types of inhibitors?

A

competitive inhibitors, non-competitive inhibitors and feedback inhibitors

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29
Q

what are competitive inhibitors?

A

they are molecules that have a similar shape to the substrate molecule and compete for the available active site on the enzyme.

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30
Q

how does competitive inhibitors lower reaction rate?

A

if the competitive inhibitors manage to bind to the active site, the active site is now blocked, substrate molecules cannot bind, reducing the reaction rate.

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31
Q

what way can we overcome competitive inhibitors?

A

increasing substrate concentration can reverse the effect of competitive inhibition

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32
Q

how do non-competitive inhibitors affect/ reduce reaction rate?

A

a non-competitive inhibitor molecule does not combine directly with the active site of the enzyme, it binds to another area. This changes the shape of the enzyme, indirectly affecting the shape of the active site and preventing the enzyme-substrate complex from being made.

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33
Q

how do feedback inhibitors reduce the reaction rate?

A

as the concentration of an end product builds up, some of it binds to the enzyme. This slows down the reactions int the pathway.

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34
Q

what is cellular respiration?

A

it’s a series of metabolic pathways that release energy from food.

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35
Q

what is the high energy compound that cellular respiration regenerates?

A

ATP (adenosine triphosphate)

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36
Q

what is phosphorylation?

A

an enzyme controlled process where a phosphate group is added to a molecule. ATP is broken down into adp+pi. the released phosphate can phosphorylate other molecules.

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37
Q

what are the 3 stages of cellular respiration

A

glycolysis, citric acid cycle, electron transport chain.

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38
Q

what is the location of the 3 stages of cellular respiration?

A

-glycolysis(cytoplasm)
-citric acid cycle (matrix (central part)of the mitochondria)
electron transport chain (inner mitochondrial membrane)

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39
Q

what is glycolysis?

A

its the breakdown of glucose into pyruvate through a series of enzyme-controlled reactions O2 is not required.

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40
Q

describe the process of glycolysis from glucose to pyruvate- the 2 phases.

A
  • glucose is first converted into intermediate products. this phase is the energy investment phase and requires energy in the form of 2 ATP
  • in the energy pay off stage, 4 molecules of ATP are formed. this results in a net gain of 2 molecules of ATP
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41
Q

what is the enzyme dehydrogenase used for in glycolysis?

A

they remove hydrogen ions and electrons from molecules. they are passed to the coenzyme NAD.this forms NADH

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42
Q

what is the citric acid cycle?

A

only occurs if o2 is present and is a series of dehydrogenase enzyme-controlled reactions resulting in the generation of ATP and releases CO2 and hydrogen.

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43
Q

what is pyruvate converted to in the citric acid cycle?

A

it’s converted to acetyl which combines with co-enzyme A to form acetyl co-enzyme A

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44
Q

what happens to the hydrogen ions and electrons from NADH that is released by citrate?

A

first of all the dehydrogenase enzyme takes more of the hydrogen ions and electrons, with then are passed onto NAD to form NADH. the hydrogen ions and electrons from the NADH is then passed onto the electron transport chain- 3rd and final stage of cellular respiration.

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45
Q

what is the electron transport chain (ETC)?

A

only occurs if o2 is present and used the hydrogen ions and electrons from NADH to generate ATP and form water. More specifically a series of carrier proteins attached to the inner mitochondrial membrane.

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46
Q

describe the process of ETC

A
  • hydrogen ions and electrons from NADH are passed onto ETC
  • the electrons are passed along the ETC, releasing energy
  • the energy is used to pump hydrogen ions across the inner mitochondrial membrane
  • the hydrogen ions flow through the ATP synthase protein back through the inner membrane
  • the flow of hydrogen ions through ATP synthase generates ATP.
  • hydrogen ions combine with the electrons and o2 ( which acts as the final hydrogen acceptor) to form water.
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47
Q

what happens if o2 is absent?

A

a process called fermentation takes place? fermentation does not generate ATP after glycolysis.

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48
Q

why does fermentation result in less ATP being produced compared to aerobic respiration?

A

it’s less efficient than aerobic respiration. fermentation does not generate ATP after glycolysis.

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49
Q

why does fermentation not become a problem in animal cells in terms of efficient reaction?

A

pyruvate is converted to lactate in a reversible reaction. so if o2 were to be available then lactate could be converted back to pyruvate and then the process of aerobic respiration could continue on as normal

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50
Q

why does fermentation become a problem in plant and yeast cells in terms of efficient reaction?

A

pyruvate is converted to ethanol and co2 in an irreversible reaction. even if o2 were to become available the ethanol and co2 would not be able to be converted back to pyruvate to proceed onto the process of aerobic respiration.

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51
Q

what is metabolic rate?

A

the quanitiy of energy consumed by an organism per unit of time

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52
Q

state the 3 varieties metabolic rate can be measured as?

A
  • the volume of oxygen consumed per unit of time
  • the volume of carbon dioxide produced per unit of time
  • the heat produced per unit of time
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53
Q

what 4 things can be used to measure metabolic rate?

A
  • respirometer
  • calorimeter
  • co2 probe
  • o2 probe
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54
Q

how do respirometers work?

A

co2 produced by respiration is absorbed by sodium hydrogen pellets. as o2 is used up, the liquid level will rise. this is measured to see the volume of o2 used per unit of time.

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55
Q

why do birds and mammals have different circulatory systems to reptiles, amphibians and fish?

A

birds and mammals have a higher metabolic rate than reptiles, amphibians and fish. to support these different metabolic rates, these organisms have different circulatory systems as they require more efficient delivery of oxygen to their cells.

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56
Q

what are the 2 main components of the circulatory system?

A
  • the heart
  • blood vessels
  • blood
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57
Q

What do we mean by organisms with high metabolic rate require efficient delivery of oxygen to cells?

A

this means that they need transport systems that can efficiently deliver large supplies of oxygen to respiring cells

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58
Q

what are the features of the circulatory system in mammals and birds?

A
  • birds and mammals have a complete double circulatory system featuring:
  • 2 atria
  • 2 ventricles
  • chambers separated by a septum
  • blood moves through the heart twice in each circuit
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59
Q

why does the complete double circulatory system enable for a more efficient oxygen delivery to cells?

A

in complete double systems, there is no mixing of deoxygenated and oxygenated blood. blood can be pumped at a higher pressure meaning efficient delivery.

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60
Q

why is the complete double circulatory system the most advanced in maintaining metabolic rates? higher

A

it enables endothermic (warmer blood) vertebrae to get larger volumes of oxygen to respiring tissues. these tissues then release heat to keep the body warm. these features allow the organism to maintain a higher metabolic rate

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61
Q

what are the features of the circulatory system in amphibians and reptiles?

A
  • amphibians and most reptiles have an incomplete double circulatory system featuring:
  • 2 atria
  • 1 ventricle
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62
Q

why is the circulatory system in amphibians and reptiles described as incomplete?

A
  • the right atrium receives deoxygenated blood returning from the body tissue’s capillary bed.
  • the left atrium receives oxygenated blood from the capillary bed in the lungs
  • the blood from both atria is passed into the single ventricle and mixes before being pumped back out to the body
  • due to this it is described as incomplete as there is only one ventricle and some mixing of oxygenated and deoxygenated blood occurs
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63
Q

what are the features of the circulatory system in fish?

A
  • fish have a single circulatory system featuring
  • 1 atrium
  • 1 ventricle
64
Q

why is the circulatory system deliver blood to the body capillaries at low pressure?

A
  • the blood only passes through the heart once in each complete circuit
  • blood travels at a high pressure to the gills oxygen is obtained from water
  • this causes a drop in pressure meaning that blood is delivered to the body capillaries at low pressure
65
Q

what are some of the factors that affect the ability of an organism to maintain it’s metabolic rate?

A

the ability of an organism to maintain it’s metabolic rate is affected by external abiotic factors such as pH, salinity and temperature

66
Q

how do animals and mammals adapt to the external abiotic factor changes in order to maintain metabolic rate?

A
  • avoidance
  • conforming
  • regulating
67
Q

what are conformers?

A

conformers are organisms whose internal environment is dependant on their external environment. they cannot alter normal metabolic rate by psychological mechanisms

68
Q

what happens to a conformers internal environment factors as the level of a factor in the external environment increases.

A

as the level of a factor in the external environment increases, the factor in the conformers internal environment increases.

69
Q

how do conformers maintain optimum metabolic rate?

A

conformers make behavioural responses to tolerate variation in their external environment

70
Q

what are the advantages and disadvantages of being a conformer?

A

advantages: low metabolic costs save energy
disadvantages: the organism is restricted to a narrow ecological niche as it is less adaptable to environment change

71
Q

what are regulators?

A

regulators are organisms which use energy from their metabolism to maintain their internal environment at a steady state regardless of changes to their external environment

72
Q

what happens to a regulators internal environment factors as the level of a factor in the external environment increases.

A

as the level of a factor in the external environment increases, the factor in the conformers internal environment stays constant.

73
Q

what are the advantages and disadvantages of being regulators?

A

advantages: the organism can live in a wide range of ecological niches
disadvantages: high metabolic costs

74
Q

what is homeostasis?

A

homeostasis is where an organism maintains a constant internal environment irrespective of the external environment.

75
Q

what are the characteristics of the process of homeostasis?

A
  • requires energy from metabolism
  • is controlled by negative feedback
  • is essential in thermoregulation
76
Q

what is negative feedback system made up of?

A
  • receptors
  • messages
  • effectors
  • used by regulators to achieve homeostasis
77
Q

how does negative feedback system achieve homeostasis

A
  • when a factor increases above a certain threshold, mechanisms are stimulated to decrease the factor
  • when a factor decreases too much , mechanisms are stimulated to increase levels back to it’s set points
78
Q

what are the requirements of negative feedback systems?

A
  • setpoints
  • receptors
  • message
  • effectors
79
Q

what is a setpoint?

A

normal level of factor in the body

80
Q

what’s the function of receptors in negative feedback?

A

detect the level of a factor

81
Q

what’s the function of messages in negative feedback?

A

sent if levels are too low/high. nervous impulses or hormonal in mammals

82
Q

what’s the function of effectors in negative feedback?

A

parts of the body which carry out a response

83
Q

what is the hypothalamus?

A

the hypothalamus is the temperature monitoring part of your brain

84
Q

what is thermoregulation?

A

thermoregulation is the process of maintaining your core internal temperature.

85
Q

what does thermoregulation ensure optimal temp. in the body for?

A
  • optimal enzyme activity to maintain metabolism

- high diffusion rates to maintain metabolism

86
Q

what are 3 parts of the body that are involved in the process of thermoregulation?

A
  • hypothalamus: in the brain
  • nerves: throughout the body
  • effectors: throughout the body
87
Q

describe the process of thermoregulation?

A

1, receptors in the hypothalamus detect changes in body temp.

  1. messages from the hypothalamus are sent to effectors by electrical impulses through the nerves.
  2. effectors carry out responses to return body temp. to normal
88
Q

what are the 3 ways in which the body is going to respond to an increase in temp. through thermoregulation?

A
  • sweating
  • vasodilation
  • decrease in metabolic rate
  • when the body temp. increases corrective responses occur to lower body temp. back to it’s set points
89
Q

how does sweating work to lower body temp. back to it’s set points when there is an increase in temp.?

A

body heat is used to evaporate water in sweat. this cools the skin

90
Q

how does vasodilation work to lower body temp. back to it’s set points when there is an increase in temp.?

A

blood capillaries in the skin dilate, increasing blood flow to the skin. this increases the heat lost by radiation

91
Q

how does a decrease in metabolic rate work to lower body temp. back to it’s set points when there is an increase in temp.?

A

metabolic reactions generate heat. decreasing metabolic rate reduces heat production

92
Q

what are the 4 corrective body responses to decrease in temp. through thermoregulation?

A
  • shivering
  • vasoconstriction of blood cells
  • increase in metabolic rate
  • action of hair erector muscles
93
Q

how does a shivering work to raise body temp. back to it’s set points when there is a decrease in temp.?

A

rapid involuntary constriction of skeletal muscles generates heat

94
Q

how does a vasoconstriction work to raise body temp. back to it’s set points when there is a decrease in temp.?

A

blood capillaries in the skin constrict, decreasing blood flow to the skin. this decreases heat loss by radiation

95
Q

how does a hair erector muscles work to raise body temp. back to it’s set points when there is a decrease in temp.?

A

hair erector muscles in the skin contract. hair strand up, trapping an insulating layer of air between the hair and skin

96
Q

how does an increase in metabolic rate work to raise body temp. back to it’s set points when there is a decrease in temp.?

A

metabolic reactions generate heat. increasing metabolic rate increases heat production

97
Q

what are the 2 ways in which animals survive in conditions which vary beyond the tolerable limits for normal metabolic activity?

A

adapt: dormancy
avoid: migration

98
Q

what does dormancy cause a decrease in?

A
  • metabolic rate
  • heart rate
  • breathing rate
  • body temp.
99
Q

what are the 2 types dormancy is classified into?

A
  • predictive

- consequental

100
Q

what does predictive dormancy mean?

A

dormancy begins before the onset of adverse conditions.

the organism becomes dormant in advance of worsening conditions.

101
Q

where is predictive dormancy common?

A

common in areas where conditions are predictable and consistent. For example where there are distinct seasons

102
Q

what does consequental dormancy mean?

A

dormancy begins after the onset of adverse conditions.

the organism begins dormant in response to adverse conditions

103
Q

where is consequental dormancy common?

A

where conditions are varied and unpredictable

104
Q

what are the advantages and disadvantages of consequental dormancy?

A

advantage: the organism can remain active for longer and take advantage of available resources.
disadvantage: a sudden severe change in abiotic factor may kill of many organisms before they have become dormant.

105
Q

what are the 3 forms of dormancy?

A
  • hibernation
  • aestivation
  • daily torpor
106
Q

what is hibernation?

A

survival in winter/low temp for a period of weeks or months.

often predictive so the animal consumes extra food which is laid down as fat store to counter the lack of food.

107
Q

how does hibernation lead to minimal energy expenditure?

A

during hibernation metabolic rate drops which allows body temp. to drop to the surrounding temp. a slower heart rate and breathing rate leads to minimal energy expenditure.

108
Q

what does the hibernator do if the temp. drops too far?

A

increases it’s metabolic rate to prevent fatal drop in temp.

109
Q

what is aestivation?

A

survival in periods of high drought/ high temp.

110
Q

what is daily torpor?

A

period of reduced activity in animals with high metabolic rate. an animals rate of metabolism and activity become greatly reduced for part of every 24-hour cycle. this causes a slower heart and breathing rate and a decrease in body temp.

111
Q

why do animals rely on daily torpor to survive?

A

it reduces energy consumption during periods when searching for food would be unseuccessful

112
Q

what is migration?

A

it’s the movement of members of a species over a relatively long distance.

113
Q

how does migration avoid metabolic adversity?

A

by expending energy to relocate to a more suitable environment.

114
Q

what are the advantages and disadvantages of migration?

A

advantage: avoids metabolic adversity caused by low temp. and shortage of food.
disadvantage: huge energy expenditure to get to a more suitable environment.

115
Q

what are the two ways in which animals know to migrate?

A
  • innate behaviour: this behaviour is inherited and instinctive
  • learned behaviour: gained by previous migration experiences.
116
Q

what are the 2 common ways to track animals?

A
  • leg rings

- transmitters

117
Q

why are leg rings useful?

A

they can provide info if the bird is recaptured and the information is reported.

118
Q

what are transmitters for tracking?

A

lightweight transmitters are glued to the animal’s body or implanted under their skin. this emits signals that are picked by receivers on satellites orbiting the earth.

119
Q

what are the 3 main industries which use microorganisms in their processes?

A
  • medicine: production of vaccines and antibiotics
  • food and enzymes: production of cheese and alcohol
  • bioremediation: breakdown of sewage and toxic waste
120
Q

why are organisms ideal for use in research and industry? (5)

A
  • they are easy to culture
  • they reproduce and grow quickly
  • their food substrate is often cheap
  • they produce useful products
  • they are highly adaptable
121
Q

what is the growth medium?

A

the substance that microorganisms are grown on

122
Q

what are the environmental factors which must be controlled in order for successful microorganism growth? (4)

A
  • sterile
  • temp.
  • pH
  • O2 Levels
123
Q

why is sterility an environmental factor which must be controlled in order for successful microorganism growth?

A

aseptic techniques, steams and filters are used. this reduces competition with desired microorganisms for nutrients and reduces risk of spoilage

124
Q

why is control of temp. an environmental factor which must be controlled in order for successful microorganism growth?

A

water jackets and thermostat are used monitor and control temp. this keeps enzymes at their optimum temp.

125
Q

why is control of o2 levels an environmental factor which must be controlled in order for successful microorganism growth?

A

air inlets and paddles are used for aeration. this allows aerobic respiration to occur.

126
Q

why is control of pH levels an environmental factor which must be controlled in order for successful microorganism growth?

A

buffer or the addition of acids/ alkali keeps enzymes at their optimum pH. Most bacteria grow at pH 7, fungi usually prefer pH 5-6

127
Q

what are the 4 phases of growth of microorganisms?

A
  • lag phase
  • log (exponential) phase
  • stationary phase
  • death (decline) phase
128
Q

what is the lag phase?

A

enzymes are induced in order to metabolise substrates

129
Q

what is the log (exponential) phase?

A

the most rapid growth of microorganism due to plentiful nutrients.

130
Q

what is the stationary phase?

A

occurs due to nutrients in the culture media becoming depleted and production of toxic metabolites. Secondary metabolites are also produced (antibodies) In the wild, this confers an ecological advantage by allowing microorganisms to out complete other microorganisms

131
Q

what is the death phase?

A

occurs due to the toxic accumulation of metabolites or the lack of nutrients in the culture

132
Q

what are semi-logarithmic scales used for?

A

they are used to produce an interpret growth curves in micro-organisms

133
Q

what is the total cell count?

A

the total no. of cells present including live and dead cells.

134
Q

what is the viable cell count?

A

the total no. of living cells present. shows the death phase where cell numbers are decreasing

135
Q

what are some of the reasons why the genome of wild strains of microorganism may be improved? (4)

A
  • improve genetic stability
  • increase ability to grow on low-cost nutrient
  • increase the yield of target compound
  • easy harvesting of target compound after fermentation is complete
136
Q

what are the 2 main processes wild strains of microorganism can be improved by?

A
  • mutagenesis

- recombinant DNA technology

137
Q

what is mutagenesis?

A
  • exposing microorganisms to mutagenic agents to produce new, improved strains. these include UV light, other forms of radiation and mutagenic chemicals which result in mutation. the mutations may produce an improved strain of microorganisms
138
Q

what is recombinant DNA technology?

A

transferring genes from one organism into a microorganism. this enables the microorganism to produce plant or animal proteins that are useful to humans

139
Q

what is recombinant DNA?

A

the newly transformed host cell contains a combination of its own DNA and that from the other source joined together, called recombinant DNA

140
Q

what 2 enzymes do the manipulation of DNA require?

A
  • restriction endonuclease

- ligase

141
Q

what’s the role of restriction endonuclease in DNA manipulation?

A

cuts the desired gene out of the donor DNA and opens the plasmid for insertion.

142
Q

describe the process of the role of restriction endonuclease in DNA manipulation (6)

A
  • this enzyme recognises a specific target sequence of DNA bases called the restriction site
  • this enzyme also cuts the complementary sequence on the opposite strand
  • this restriction site also allows for specific genes of interest to be cut out of the DNA
  • where the DNA is cut by the restriction endonuclease it creates sticky ends at the end of DNA strands
  • the DNA in the plasmid is then cut with the same restriction endonuclease
  • this creates complementary sticky ends as the sticky ends of the gene and the plasmid match and can slot together
143
Q

what’s the role of ligase in DNA manipulation?

A

seals the desired gene into the plasmid

144
Q

describe the process of the role of ligase in DNA manipulation(3)

A
  • ligase then seals the target sequences of DNA into the plasmid.
  • this forms a recombinant plasmid containing recombinant DNA
  • this technology requires the use of recombinant plasmids and artificial chromosomes as vectors
145
Q

what are vectors?

A

a vector is a DNA molecule used to carry foreign genetic information into another cell

146
Q

what is the functional difference between plasmids and artificial chromosome?

A

plasmids: only capable of carrying relatively small quantities of DNA
Artificial chromosome: are capable of carrying longer DNA sequences

147
Q

when are artificial chromosomes preferable to plasmids as vectors?

A

when larger fragments of foreign DNA are required to be inserted

148
Q

what do the 2 types of vectors (artificial chromosome and plasmids) contain? (4)

A
  • restriction site
  • regulatory sequences
  • origin of replication
  • selected markers
149
Q

what are restriction sites?

A

the target sequence of DNA where specific restriction endonuclease is cut

150
Q

what are regulatory sequences?

A

control gene expression of the vectors own gene and the inserted gene

151
Q

what is the origin of replication?

A

initiates the self-replication of the vector

152
Q

what are selected markers?

A

antibiotic resistance genes protect the microorganism from a selective agent that can kill it or prevent it’s growth. this ensures only the microorganisms with vectors will grow

153
Q

what are the 2 possibilities if a plasmid has a marker gene for resistance to the antibiotic ampicillin and the microorganisms are cultured in a growth media containing ampicillin?

A
  • microorganism with the vector will survive. they have resistance
  • microorganisms without the vector will die. they do not have resistance
154
Q

what is an inactive protein?

A

Protein needs to be folded into the correct 3D structure in order to work properly (be in their active form) proteins made in recombinant bacteria are sometimes incorrectly folded, this leads to inactive protein

155
Q

what are the uses of recombinant yeast cells?

A

they are used to produce correctly folded, active forms of the protein. Yeasts are eukaryotic cells with more complex machinery that can produce more complicated protein

Biology: Unit 2 (1 decks)

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