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Higher Biology > Unit 2 > Flashcards

Unit 2 Flashcards

1
Q

What is a catabolic reaction?

A
  • Break down of complex molecules into smaller molecules

- Energy is released

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2
Q

What is an anabolic reaction?

A
  • Build up of complex molecules

- Energy is used

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3
Q

What does an enzyme do within a metabolic pathway?

A

Catalyses each step

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4
Q

What is the name of an alternative route in respiration?

A

sorbitol

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5
Q

What are membranes made up from?

A
  • Phospholipids

- Protein molecules

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6
Q

How are membranes described?

A

Fluid mosaic model

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7
Q

Definition of Diffusion?

A

Movement of molecules from a high concentration to a region of low concentration down a concentration gradient.

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8
Q

What are the 3 proteins in membranes?

A

Pumps
Pores
Enzymes

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9
Q

What do protein pores do?

A

Transport water molecules and certain ions from one side to the other; requires no energy
Span the membrane

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10
Q

What do protein pumps do?

A

Transport Sodium and Potassium ions across the membrane using energy.

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11
Q

What does Temperature, concentration of glucose and oxygen affect?

A

Rate of active transport, the rate of respiration and the release of ATP.

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12
Q

What is the role of ATP synthase?

A

Catalyses the synthesis of ATP

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13
Q

What is an important feature in cell organelles?

(ratio) and what does this allow?

A

Large surface area: volume

Allows high concentrations and reaction rates

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14
Q

What are lysosomes and what do they do?

A

They are a powerful digestive enzyme

Localise the metabolic activity of the cell.

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15
Q

What is the main substrate in respiration? and what does it do?

A

Glucose

Broken down to release energy as ATP

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16
Q

What breaks down Lactose?

A

B-galactosidase

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17
Q

What is the equation for the breakdown of Lactose?

A

Lacose = Glucose + galactose

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18
Q

What is a regulator gene?

A

Codes for a repressor molecule

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19
Q

What is a repressor gene?

A

“Switches off” the operator gene

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20
Q

What is an Operator gene?

A

Controls the structural gene by “switching it on/off”

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21
Q

What is a structural gene?

A

Codes for the enzyme B-galactosidase

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22
Q

What are the stages if Lactose is absent in the production of B-galactosidase?

A

1- Regulator gene switched on
2- Repressor molecule produced
3- Repressor molecule binds with the operator gene
4- Operator gene is switched off
5- Structural gene is switched off
6- No enzyme produced - no B-galactosidase

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23
Q

What are the stages if Lactose is present in the production of B-galactosidase?

A 
1- Regulator gene switched on
2- Repressor molecules produced 
3- Repressor molecule binds with Lactose (inducer)
4- Operator gene switched on
5- Structural gene switched on
6- Enzyme produced - B-galactosidase
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24
Q

What happens when all the lactose has been used up? and what does that prevent?

A

The repressor molecule can bind to the operator gene; switching it off - enzyme is no longer produced.
This prevents any unnecessary use of resources such as amino acids and ATP

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25
Q

What is the control of metabolic pathways due to?

A

The presence or absence of particular enzymes and the regulation of the rate of reaction of key enzymes within the pathway

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26
Q

What controls the regulation of metabolic pathways?

A

Both intra- and extra-cellular signal molecules.

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27
Q

Why are enzymes important?

A

Speed up a chemical reaction,
lower the activation energy
Remain unchanged at the end of the reaction
Biological catalysts

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28
Q

What happens at higher temperatures within a metabolic pathway?

A

The reactant molecules absorb more energy and their chemical bonds become more and more unstable.

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29
Q

What is the activation energy?

A

The energy needed to break the chemical bonds in the reactant molecules and so start the reaction.

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30
Q

What are enzymes made of?

A

Proteins

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31
Q

What determines the shape of the protein?

A

Sequence of amino acids

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32
Q

What is the shape of most enzymes?

A

Globular

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33
Q

What determines the shape of the active site?

A

Sequence of amino acids

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34
Q

What is induced fit?

A

How closely the active site fits around the substrate.

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35
Q

What are the factors needed for enzyme action?

A
  • suitable temperature
  • pH
  • supply of substrate molecules
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36
Q

Orientation of reactants

A

The substrate molecules can only fit into the active site if they are correctly orientated.

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37
Q

What is the rate of reaction against substrate concentration?

A

At low concentration, the reaction rate is low. As the substrate concentration increases, more and more of the active sites are filled.

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38
Q

What is an inhibitor?

A

A substrate that slows down or inhibits the rate of an enzyme catalysed reaction.

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39
Q

What are the 3 types of inhibitors?

A

Competitive inhibitors
Non-competitive inhibitors
Feedback inhibition or (end product inhibition)

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40
Q

What is a competitive inhibitor?

A
  • Competes with the substrate molecule for the active site.
  • Similar shape to substrate
  • rate of reaction to be slower; as the concentration of substrate increases, so does the rate of reaction
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41
Q

What is a non-competitive inhibitor?

A

Binds to another part of the enzyme, altering the shape of the active site

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42
Q

What is feedback inhibition (end product inhibition)

A

If the end product of a final reaction in a metabolic pathway builds up, it may bind to the active site or another part of the 1st enzyme. The active site is altered and the pathway stops.

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43
Q

What does feedback inhibition prevent?

A

Prevents too much end product being produced.

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44
Q

What are the 3 stages of cellular respiration?

A
  • Glycolysis
  • Citric acid cycle
  • Electron transfer
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45
Q

What is the ATP released in respiration used for?

A

Active transport, DNA Replication, protein synthesis, cell division and contraction of muscle fibres

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46
Q

What is the word equation for respiration?

A

Glucose + oxygen = carbon dioxide + water + ATP

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47
Q

What can Pyruvate be broken down into during Fermentation?

A

Lactate (3C) or ethanol (2C) + CO2 (1C)

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48
Q

What happens when Glucose is broken down?

A

Hydrogen ions and electrons are removed

energy is released

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49
Q

What removes hydrogen ions and high-energy electrons?

A

Dehydrogenase enzymes

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50
Q

What is Phosphorylation?

A

An enzyme-catalysed chemical reaction that attaches a phosphate group to another

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51
Q

Where does Glycolysis occur?

A

In the cytoplasm

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52
Q

What are the two stages of Glycolysis?

A
  • Energy investment stage

- Energy pay-off stage

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53
Q

What happens during the 1st stage of Glycolysis?

A

Glucose turns into an intermediate

2ATP -> 2ADP + Pi

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54
Q

What happens during the 2nd stage of Glycolysis?

A

The intermediate turns into 2x Pyruvate
4ADP + Pi -> 4ATP
2NAD -> 2NADH

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55
Q

What happens if oxygen is present during Glycolysis?

A

Pyruvate enters the second stage; the citric acid cycle then electron transfer stage

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56
Q

Where does the citric acid cycle take place?

A

Matrix of the mitochondria

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57
Q

Benefit of a folded inner membrane?

A

increases the surface area so more of the electron transport chain molecules can fit in

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58
Q

What is the main site of ATP synthesis

A

Mitochondria

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59
Q

What helps maintain high reaction rates?

A

Accumulation of reactants

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60
Q

What is needed for the citric acid cycle to occur?

A

Oxygen

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61
Q

What is Pyruvate broken down into?

A

Carbon dioxide and an acetyl group

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62
Q

What does the acetyl group combine with? and what does it form?

A

Combines with Coenzyme A to produce: Acetyl Coenzyme A

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63
Q

What does Acetyl Coenzyme A join with when entering the cycle? and what does the form?

A 
Oxaloacetate (4C)
Forms Citrate (6C)
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64
Q

Name another Hydrogen carrier present in the citric acid cycle?

A

FAD -> FADH2

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65
Q

What happens when electrons are passed down the electron transfer chain?

A

Energy is released

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66
Q

What is the energy used for during the Electron Transfer chain?

A

Used to pump hydrogen ions from the mitochondrial matrix to the inner membrane space

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67
Q

How to hydrogen ions return to the matrix?

A

Through a channel in the enzyme ATP synthase

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68
Q

What is needed for the electron transfer chain?

A

Oxygen

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69
Q

What does the Electron transfer chain produce?

A

The most ATP molecules

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70
Q

What releases the high energy electrons?

A

NADH and FADH2

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71
Q

What is oxygen described as during the Electron transfer chain?

A

The final electron acceptor

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72
Q

What is the word equation for the Electron transfer chain?

A

Low energy electrons + hydrongen ion + oxygen = Water

e- + 2H+ + 1/2 O2 = H2O

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73
Q

How many molecules of ATP does the electron transfer chain generate?

A

34 molecules

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74
Q

What is the total amount of ATP molecules from respiration?

A

38 ATP

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75
Q

What can be broken down to make Glucose, used in respiration?

A

Starch

Glycogen

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76
Q

What other sugars can be converted into Glucose or other intermediates?

A

Sucrose, Lactose and Maltose

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77
Q

What can be used as alternative respiratory substrates in respiration?

A

Fats and proteins

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78
Q

What can fat molecules be broken down into? and what are they converted into?

A

Glycerol - an intermediate

Fatty acids - Acetyl Coenzyme A

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79
Q

What are proteins digested into? and what are they converted into?

A

Amino acids - Pyruvate, Acetyl Coenzyme A and intermediates in the citric acid cycle

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80
Q

What piece of apparatus measures oxygen consumption?

A

Respirometer measures oxygen uptake over a period of time

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81
Q

What is used to measure metabolic rate (apparatus)

A

Calorimeter

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82
Q

How can metabolic rate be measured?

A

Monitoring an animals heat loss

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83
Q

In unicellular organisms, how to exchanges occur? (oxygen delivery)

A

Directly with the external environment

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84
Q

In which type of organisms are closed circulatory systems found?

A

All vertebrates and few invertebrates

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85
Q

What is an advantage about closed circulatory systems?

A

Blood is carried at high pressure which enables efficient delivery of O2 and nutrients to the cells of larger and more active animals

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86
Q

Features of arteries :

A
  • carry blood away from the heart
  • High pressured blood
  • thick muscular walls; withstand the pressure
  • narrow central lumen
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87
Q

Features of Veins :

A
  • Carry blood back to the heart
  • lower pressure
  • Valves prevent backflow of blood
  • thinner muscular walls
  • Larger central lumen
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88
Q

Features of capillaries :

A
  • Walls are only one cell thick

- Across the thin walls; the exchange of dissolved gases and other chemicals occur

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89
Q

Single circulatory system:

A

A fish
Two chambers
Blood only passes through the heart once

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90
Q

Disadvantages of a single circulatory system

A

reduces pressure so limits the rate that the blood can flow

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91
Q

Features of double circulatory systems:

A
  • Birds and mammals
  • 2 atria and 2 ventricle
  • no mixing of blood
  • oxygen rich blood and oxygen poor blood
  • blood passes through the heart twice
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92
Q

Features of incomplete circulatory systems:

A

Frogs and other amphibians

  • 3 chambers [ 2 atria and 1 ventricle ]
  • mixing of blood
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93
Q

What is the metabolic rate of a fish?

A

Low

94
Q

What is the metabolic rate of a Reptile and an Amphibian?

A

Low

95
Q

What is the metabolic rate of a bird?

A

High

96
Q

What is the metabolic rate of a mammal?

A

Very high

97
Q

What are the 2 types of lungs ?

A 
Alveolar lungs (mammals)
Septate lungs (one giant alveolus)
98
Q

When is gas exchange fast?

A

When the area for diffusion is large and the path for diffusion is short

99
Q

Lung arrangement in Amphibians:

A
  • Diffusion of gases across its external body surface
  • Skin has a dense network of capillaries
  • Diffusion takes place directly through the skin as blood vessels are close to the permeable skin
100
Q

Internal anatomy of snakes?

A

They reply on muscles used in locomotion to ventilate their lungs

101
Q

What does a Trachea do?

A

Splits into the two primary bronchi airways that direct air into either the left or right lung.

102
Q

What kind of lungs do snakes have?

A

Septate

103
Q

How many airsacs do Birds have and what do they act as?

A

8 or 9

They act as “bellows” to keep air flowing through the lungs

104
Q

In birds, what is the site of gas exchange called?

A

Tiny channels called parabronchi

105
Q

What is unusual about the passage of air in birds? and what does that improve?

A

requires 2 cycles of inhalation and exhalation

- Improves efficiency of ventilation and provides the bird with high levels of O2.

106
Q

What are the 2 airsacs called in birds?

A

Posterior

Anterior

107
Q

How do animals transport most of their oxygen?

A

Bound to proteins called respiratory pigments

108
Q

What happens if the tissues don’t receive enough oxygen? (high altitudes)

A

The kidneys synthesise and secrete the hormone erythropoietin (EPO) that stimulates the generation of more erythrocytes (red blood cells)

109
Q

What is TheVO2 max?

A

The volume of oxygen used by the person, per kilogram of body mass, per minute.

110
Q

“the higher the value for VO2 max…”

A

the greater the aerobic fitness for that individual

111
Q

What are organisms affected by?

A

Abiotic factors such as pH, water salinity or temperatures

112
Q

What happens if an organism is not living in its optimal abiotic conditions?

A

The population density is lower

113
Q

What are abiotic factors a major factor in determining?

A

The distribution of a species

114
Q

What is a Conformer?

A

Allows its internal conditions to change in accordance with changes in the variable

115
Q

What is a Regulator?

A

Uses internal mechanisms to control internal changes in the face of external fluctuations.

116
Q

What are Regulators able to alter?

A

Their normal metabolic rate by employing physiological means

117
Q

What is Tolerance?

A

If the change of the conditions is small, the conformer is still able to function

118
Q

How is a Conformers ability to control internal environment by physiological means?

A

Limited

119
Q

How is a Regulators ability to control internal environment by physiological means?

A

Efficient

120
Q

What do conformers have in terms of ecological niches that can be exploited?

A

Narrow range

121
Q

What do Regulators have in terms of ecological niches that can be exploited?

A

Wider range

122
Q

What strategy to conformers have?

A

Behavioural

123
Q

What strategy do regulators have?

A

Physiological

124
Q

What is Negative Feedback control?

A

A principle which brings about Regulation.

Corrective mechanisms are switched on and effector organs respond.

125
Q

What does Negative Feedback control require?

A

Energy

126
Q

What can body temperatures outside the normal range do?

A

Can reduce the efficiency of enzymatic reactions and alter the fluidity of cellular membranes with potentially fatal results

127
Q

What happens when there is a DECREASE in body temperature?

A
  • Shivering
  • increased metabolic rate
  • sweating decreases
  • vasoconstriction
  • hair erector muscles contract
128
Q

What detects that their is an increase/decrease in body temperatures?

A

Thermoreceptors in the hypothalamus (skin)

129
Q

What happens when there is an INCREASE in body temperature?

A
  • decreased metabolic rate
  • sweating increases
  • vasodilation
  • hair erector muscles relax
130
Q

What is the role of the hypothalamus?

A

Sending appropriate nerve impulses to the effector organs

131
Q

What is the role of the skin?

A

leading role in temperature regulation

132
Q

What is Vasodilation?

A

When arterioles leading to the skin become dilated, which increases the volume of blood at the skin surface and as a result; heat lost by radiation increases

133
Q

What is Vasoconstriction?

A

When arterioles leading to the skin become constricted. This limits the volume of blood at the surface of the skin and therefore less heat lost through radiation

134
Q

What features do Ectotherms have?

A
  • Gain most of their heat from external sources
  • unable to regulate its body temperature
  • have behavioural means
  • lower metabolic rates
135
Q

What features do Endotherms have?

A
  • warmed mostly by heat generated by metabolism
  • steady body temperature
  • high metabolic rates
136
Q

What are all metabolic processes within an organism controlled by?

A

Enzymes

137
Q

Within enzyme activity, what happens to reactant molecules when temperatures rises?

A

Have more and more kinetic energy , which increases the chances of successful collisions and this increases the rate of reaction

138
Q

What happens to enzymes when temperature goes above 37 degrees?

A

Enzyme structure begins to denature as bonds break and the active site changes.

139
Q

What are diffusion rates?

A

The rate of diffusion of a substance is directly proportional to the temperature.

140
Q

What happens to molecules of a substance at high temperatures?

A

Have greater kinetic energy and therefore diffuse at a faster rate

141
Q

Reduction in metabolic rate

A

The mechanism involves some reduction of the metabolic rate to minimise the energy expenditure

142
Q

What is dormancy?

A

When an organisms metabolism is reduced to promote survival during adverse conditions

143
Q

What are the 2 types of Dormancy?

A

Predictive or consequential

144
Q

What is predictive dormancy?

A

a regular pattern, before the onset of the adverse conditions

145
Q

What is consequential Dormancy?

A

less predictable habitats, enter a period of dormancy in response to the arrival of the adverse condition

146
Q

What is Torpor?

A

A period of reduced activity in organisms with high metabolic rates. They save energy while avoiding difficult and dangerous conditions

147
Q

What happens to the organism during Torpor?

A

A short time energy saving response
breathing and heart rate decreases
body temperature falls
oxygen consumption is lowered

148
Q

What is Hibernation?

A

An extended period of torpor; an adaptation to cold winter conditions and food scarcity

149
Q

What happens to the organism during Hibernation?

A
  • body temperature drops and its internal “thermostat” is turned down
  • breathing rate falls
  • heart rate is lowered
  • oxygen consumption decreases as metabolic rate drops
150
Q

What is Aestivation?

A

Response to the onset of very hot and dry conditions

151
Q

What happens to the organism during Aestivation?

A
  • Metabolic rate drops
  • heart rate drops/stops
  • breathing rate stops
152
Q

What is Migration?

A

A regular, long distance change in location which is to avoid metabolic adversity

153
Q

Advantages of migration include:

A
  • Access to more favourable feeding opportunities
  • avoidance of extreme of temperatures
  • better breeding grounds with fewer predators
154
Q

What are the factors which trigger migration?

A

Decreased number of daylight hours, temperature, changes in food availability and genetic factors

155
Q

What provides signals that guide migration?

A

Environmental stimuli

156
Q

What is Photoperiod?

A

The length of time that is in daylight; primary trigger to migration

157
Q

What does increasing photoperiod do?

A

Stimulates the production of hormones and other physiological changes that prepare a bird for migration

158
Q

Name techniques used for observing and tracking migratory behaviour.

A
  • Tagging and ringing (metal bands)
  • satellite tracking (waves)
  • Radar (pulses of electromagnetic waves)
159
Q

What is innate behaviour?

A

When it will be observed by all individuals in a population; fixed, flexible and inherited

160
Q

What is learned behaviour?

A

Acquired or modified as a result of the specific experiences of an individual.
Vary between members of the same species

161
Q

What are extremophiles?

A

Organisms that can live in environments so extreme that to most other organisms, the conditions would be fatal.

162
Q

What “extremes” can extremophiles thrive in?

A

extremes of temperatures, high sulphur and salt levels and complete absence of oxygen

163
Q

What is an example of an extremophile?

A

Thermophilic bacteria living in hot springs or seabed vents may generate ATP by removing high energy electrons from inorganic molecules.

164
Q

What are the 3 domains of life?

A

Archaea
Bacteria
Eukaryotes `

165
Q

What is another name for microorganisms?

A

Microbes

166
Q

Microorganisms are said to be:

A

Highly adaptable and able to make use of a wide variety of substances for their metabolism

167
Q

Where are microorganisms found?

A

A wide range of ecological niches

168
Q

What must every organism obtain?

A

all of the substances required for energy generation and cellular biosynthesis from its environment

169
Q

What is bacteria grown in?

A

Culture medium

170
Q

What are the chemicals and elements that are used for bacterial growth?

A

Nutrients or nutritional requirements

171
Q

What do microorganisms require?

A

An energy source which may be chemical or light.

172
Q

What other requirements might some microorganisms need?

A

A supply of raw materials to produce cellular building blocks such as amino acids and nucleotides.

173
Q

What specific complex molecules might some microorganisms need?

A

Fatty acids or certain vitamins to be present in their growth medium

174
Q

In the growth of a microorganism, what are the correct ranges of physical conditions required?

A

Oxygen concentration, temperature and pH

175
Q

What are microorganisms normally grown in?

A

Liquid medium (broth) or on a solid medium (agar jelly)

176
Q

What is the growth medium contain within?

A

Petri dishes, flasks or bottles

177
Q

Industrially, what are microorganisms cultured in?

A

Industrial fermenters (bioreactor)

178
Q

What are the features of an Industrial fermenter?

A
  • Water jacket
  • Filter
  • Thermostatic control
  • Air inlet
  • Paddle
179
Q

What is the function of the Water jacket?

A

Maintains temperature by continual stream of cold water

180
Q

What is the function of the Filter

A

Maintains sterility by filtering out air-borne microorganisms

181
Q

What is the function of the Thermostatic control?

A

Controls temperature of cold water in jacket

182
Q

What is the function of the air-inlet?

A

Controls oxygen levels; providing steam of air

183
Q

What is the function of the paddle?

A

mixes culture and growth medium

184
Q

What optimum environmental conditions must be maintained to produce the maximum yield of a product?

A
  • sterility
  • suitable temperature
  • oxygen levels
  • pH
185
Q

What is sterility?

A

The growth of unwanted microorganisms is prevented using aseptic techniques

186
Q

Examples of sterility:

A

all equipment and culture media; by heating under pressure in an autoclave or in large industrial fermenter vessels, steam cleaned

187
Q

What are the 4 stages in growth of unicellular organisms?

A
  • lag phase
  • exponential (log) phases
  • stationary phase
  • death phases
188
Q

What happens during the lag phase?

A

There is little or no increase in cell number; enzymes are induced

189
Q

What happens during the exponential phase?

A

Cells grow and multiply at the maximum rate

190
Q

The exponential growth takes place due to what?

A

high availability of substrate and conditions which are close to optimal.

191
Q

What happens during the stationary phase?

A

The number of cells produced by binary fission is equal to the number of cells dying so the growth rate is 0.
Cells produce secondary metabolites

192
Q

What is the stationary phase due to?

A

the nutrients in the culture medium being depleted

193
Q

What happens during the death phase?

A

number of cells dying is greater than the number of new cells dividing

194
Q

What is the death phase due to?

A

The lack of substrates and toxic accumulation of metabolites

195
Q

What is mean generation time (doubling time)?

A

The time taken for a cell to divide into 2

196
Q

What does a total cell count involve?

A

counting all cells present in the sample whether alive or dead

197
Q

What does a viable cell count involve?

A

counting only the number of cells which are alive and able to grow

198
Q

What are primary metabolites?

A

compounds related to the synthesis of microbial cells and are produced in the active growth phase (exponential)

199
Q

What do primary metabolites include?

A

amino acids and nucleotides

200
Q

What are secondary metabolites?

A

population is in the stationary growth phase and are of economic value.

201
Q

What is a precursor?

A

large quantities of an early metabolite

202
Q

What is an inducer ?

A

Induced the formation of certain key enzymes

203
Q

What is an inhibitor?

A

Reduces or stops the activity of an enzyme

204
Q

How can the wild strain of microorganisms be improved?

A
  • Mutagenesis
  • Selective breeding and culture
  • Recombinant DNA
205
Q

What is Mutagenesis?

A

a process which changes the genetic information of an organism and results in a mutation

206
Q

What is selective breeding and culture?

A

individual strains of microorganisms each with desirable characteristics are selected and allowed to breed

207
Q

What are 2 examples of desirable characteristics?

A

rapid growth and genetic stability

208
Q

Transfer of DNA is always what?

A

one way

209
Q

What is horizontal gene transfer?

A

when some bacteria can transfer plasmids or pieces of chromosomal DNA to each other to produce new strains

210
Q

What happens when bacteria dies?

A

Their DNA may be released into the environment

211
Q

What is recombinant?

A

When a different cell now contains DNA fro from two different cells combined

212
Q

What is one aim of recombinant DNA technology?

A

to obtain many copies of a particular gene; by marking transgenic bacteria or yeast cells containing the desired gene

213
Q

what does recombinant DNA technology enable?

A

transfer gene sequences from one organism to another

214
Q

What is a safety mechanism of genes being introduced?

A

to prevent the microorganisms from surviving in an external environment

215
Q

What does restriction endonuclease do?

A

cuts the DNA into smaller fragments

216
Q

What 3 features does a plasmid have?

A
  • restriction site
  • origin of replication
  • marker gene(s)
217
Q

What is a restriction site?

A

a specific sequence of bases on the plasmid’s DNA

218
Q

What can the restriction endonuclease produce?

A

Sticky ends

219
Q

What is the origin of replication?

A

the one point where DNA synthesis always begins.

220
Q

What does the origin of replication contain?

A

genes that control its self-replication

221
Q

What is important about the origin of replication?

A

the one point where DNA synthesis always begins.

222
Q

What is the function of the marker gene?

A

enables the scientist to determine whether a host cell has taken up the recombinant plasmid or not.

223
Q

What do plasmids act as?

A

Vectors

224
Q

What can plasmids be used for?

A

to transfer a section of DNA from one organism to another

225
Q

What does a plasmid have? (4)

A
  • only one origin of replication
  • multiple regulatory sequences
  • two or more genes with particular properties such as resistance
  • only one restriction site
226
Q

What is ligase used for?

A

to seal the open plasmid

227
Q

advantage of artificial chromosomes:

A

can carry far more foreign DNA than a plasmid.

228
Q

What is a consequence of bacteria not containing introns?

A

the desired protein may be incorrectly folded or lack post-translational modifications.

229
Q

Why are safety procedures put in place?

A

to limit the occurrence of any potential hazards.

230
Q

What do aseptic techniques include?

A
  • use of sterile equipment
  • sterilising working areas
  • thoroughly washing hands before and after all procedures
231
Q

Definition of ethics

A

the moral principles governing or influencing conduct.

232
Q

Examples of microorganisms made from microorganisms that could be used as a biological weapon:

A
  • anthrax
  • smallpox
  • ricin

Higher Biology (4 decks)

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