Brainscape's Knowledge GenomeTM

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


See full index

Biology Topic 5 > Topic 8 > Flashcards

Topic 8 Flashcards

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

What will an exposure to red light trigger

A

Germination

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

What will an exposure to far-red light inhibit

A

Germination

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

What happens when a plant absorbs red (natural) light

A

Phytochrome is converted from inactive Pr to active Pfr
In the dark, Pfr slowly converts back into Pr
If exposed to far red light, it will change back rapidly

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

Define long day plants

A

Only flower when day length exceeds a critical value
When uninterrupted darkness is less than 12hrs
Need high levels of Pfr

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

Define short day plants

A

Only flower when uninterrupted darkness is greater than 12hrs
Need low levels of Pfr, therefore more Pr

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

What else, other than germination, does exposure of phytochromes to light stimulate

A

Development of primary leaves
Leaf unrolling
Production of pigments

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

How is greening of the shoot promoted

A

Causes the phytochromes to change shape through a series of interactions with other signal proteins
They activate transcription factors which cause the synthesis of enzymes that control chlorophyll production in greening of the shoot

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

What are phytochromes

A

Photoreceptors

That absorb red or far red light

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

Define the central nervous system

A

Part of the nervous system that consists of the brain and spinal cord

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

Define autonomic nervous system

A

Nervous response from his part of the nervousness system are involuntary and involve the smooth muscle

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

Define sympathetic nervous system

A

Prepares the body for fight or flight

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

Define parasympathetic nervous system

A

Prepared the body for rest and digest

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

What is the resting potential

A

The inside of an axon is more negative than the outside, making the membrane polarised at -70mV
Due to an uneven distribution of ions across the cell surface membrane

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

How is the resting potential created within an axon

A

1) Na/K+ pumps create a concentration gradient across the membrane
2) k+ diffuse out of the cell down the conc gradient, making the outside of the membrane positive and the inside negative
3) electrical gradient will pull K+ back into the cell
4) at -70mV there is no net movement of K+ as the electrical gradient balances the chemical gradient

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

How is an action potential generated in an axon

A

1) voltage dependent gated Na+ channels open, allowing Na+ to flow into the axon, depolarising the membrane
2) the Na+ channels close whilst the voltage dependent gated K+ channels open, allowing K+ to leave the axon, repolarising the membrane
3) the membrane is hyperpolarised
4) the K+ channels close but K+ diffuse back into the axon through K+ channels to recreate the resting potential

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

What is the place two neurones meet at known as

A

A synapse

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

What is the neurotransmitter called used at a Cholinergic Synapse

A

AcetylCholine

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

What is the sequence of events at a synapse

A

1) an action potential arrives
2) the membrane depolarises allowing Ca2+ channels to open
3) the influx of Ca2+ causes synaptic vesicles to fuse with the presynaptic membrane
4) the neurotransmitter binds with receptors on the post-synaptic membrane causing Na+ channels to open
5) membrane depolarises and initiates an action potential

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

How is the neurotransmitter removed from the synaptic cleft

A

It is either broken down by enzymes

Or reabsorbed into the presynaptic neurone

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

Define excitatory synapse

A

Makes a membrane more permeable to sodium ions and therefore leads to depolarisation and an action potential

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

What are inhibitory synapses

A

They make it less likely for an action potential to be produced in the post synaptic neurone
The channels for chloride and potassium ions are opens in the post, causing it to become hyperpolarised

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

Define summation

A

Each action potential adds to the effect

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

What are the two types of summation

A

Spatial

Temporal

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

Define spatial summation

A

A single exciting synapse typically does not depolarise the post synaptic membrane to generate an action potential

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

Define temporal summation

A

Several impulses arriving within a short time cause depolarisation via the release of neurotransmitter

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

What are the general structures of a neurone

A 
Cell body containing a nucleus
Dendrites
Terminal branches
Axon
Schwann cells
Node of ranvier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is a myelinated neurone

A

Myelin is a layer of lipid produced by Schwann cells

It electrically insulated the neurone

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

What are the two antagonistic muscles contained within the iris

A

Circular and radial

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

What did circular and radial muscles in the iris do

A

Control the size of the iris under the influence of the autonomic nervous system

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

How do iris muscles react in high light intensities

A

1) Rods cause nerve impulse to pass along the optic nerve to a group of nerve cells in the brain
2) impulses sent along sympathetic motor neurone to circular muscles
3) circular muscles contract , causing pupils to constrict

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

How do iris muscles react in low light intensities

A

1) fewer impulses reach the coordinating centre in the brain
2) impulses are sent down the sympathetic motor neurone to radial muscles
3) radial muscles contract, causing pupils to dilate

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

What is photoperiodism

A

Plants flower and seeds germinate in response to changes in day length

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

What is phototropism

A

Tropisms are growth responses in plants where the direction of the growth response is determined by the direction of external stimulus

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

What is the response known as if a plant growths towards a stimulus

A

Positive

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

What is the effector for growth response in plants

A

Cell elongation

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

Where does cell elongation occur and how is it controlled

A

Just below the tip of the shoot

By the plant growth substance IAA (an auxin)

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

Define stimuli

A

Any changes that occur in an animals environment

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

What are the two main photoreceptors

A

Rods and cones

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

What conditions do rod cells work in

A

Black and white

Work in both low and high light intensities

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

What conditions do come cells work in

A

Colour

High light intensities

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

How does light stimulate photoreceptor cells

A

1) rhodopsin is broken down into retinal and Olson
2) Na+ channels close whilst Na+ is actively pumped out of the membrane
3) the membrane becomes hyperpolarised
4) no neurotransmitter is released
5) cation channels in the bipolar cell open and the membrane becomes depolarised,generating an action potential in the neurone of the optic nerve

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

How do photoreceptors cells function at resting state (in the dark)

A

1) Na+ diffuse in through open cation channels
2) Na+ move down the conc gradient
3) Na+ is actively pumped out of the membrane
4) the membrane slightly depolarises due to influx of Na+
5) neurotransmitter, Glutamate, is released and binds to the. I polar cell, preventing it depolarising

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

What is the main section of the brain called and what is it comprised of

A

The cortex

Two cerebral hemispheres

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

What connects the two cerebral hemispheres of the brain and what is it made of

A 
Corpus callosum 
White matter (axons)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What four regions is each hemisphere made up of

A

Frontal lobe, parietal lobe, occipital one and temporal lobe

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

What areas of the brain is responsible for the ability to learn

A

Cerebral hemispheres

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

What is the function of the frontal lobe

A

Decision making
Planning
Contains primary motor cortex

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

What is the function of the parietal lobe

A

Orientation, movement, calculation

49
Q

What is the function of the occipital lobe

A

Visual cortex

50
Q

What is the function of the temporal love

A

Processing auditory information

51
Q

What is the function of the thalamus

A

Routing incoming sensory information to the brain

52
Q

What is the function of the hypothalamus

A

Contains thermoregulatory centre
Used in homeostasis
Acts as an endocrine gland

53
Q

What is the function of the hippocampus

A

Involved in laying down long term memory

54
Q

What is the function of the basal ganglia

A

Responsible for selecting and initiating stored programmes of movement

55
Q

What is the the function of the corpus callosum

A

Provides a connection between The cerebral hemispheres and the mid brain

56
Q

What is the function of the cerebellum

A

Responsible for balance

57
Q

What is the function of the midbrain

A

Relays information to cerebral hemispheres

58
Q

What is the function of the medulla oblongata

A

Regulates heart rate

59
Q

What are the main effects of a stroke

A

Brain damage may cause problems with speaking, reading and writing

60
Q

Define neural plasticity

A

The potential of neurones to change in structure and function

61
Q

What are CT Scans and how are they used

A 
Computerised Axial Tomography
Cannot be used for imaging soft tissues 
Limited resolution
2D
X-Ray's harmful
62
Q

What is MRI and how is it used

A 
Magnetic resonance imaging 
Uses a magnetic field and radio waves
3D
Higher resolution 
Not suitable for people it's pace makers
63
Q

What is fMRI and how is it used

A

Function MRI
Follows oxygen uptake to active areas of the brain
Provided information about the brain in action

64
Q

Is depth perception innate or learnt and how is it tested

A

Innate

Using a visual cliff

65
Q

What is the carpenter world hypothesis

A

Those who live in a world dominated by straight lines and right angles tend to perceive depth cues differently than those who live in a circular environment

66
Q

What does the muller-layer illusion show

A

That depth cues make us think an object is further away

67
Q

How can stem cells be used to restore vision

A

Transplanted into the eye

Bind to original cornea cells and multiply

68
Q

What allows us to interpret the depth of close objects

A

Objects less than 30m away depend on the presence of cells in the visual cortex that obtain information from both eyes at once

69
Q

What allows us to interpret the depth of distant objects

A

Objects more than 30m use visual cues and past experiences to interpret images

70
Q

Why is it important to study new born babies when studying visual development

A

Babies are born short sighted

Babies are born with characteristic behaviours

71
Q

What is a visual cliff

A

Babies are encouraged to crawl across a table made of glass or Perspex which acts as a visual cliff
Patterns are placed brown the glass to create the appearance of a steep drop

72
Q

How do axons grow

A

Neurones grow from the retina to the thalamus

73
Q

What is the visual cortex comprised of

A

Comprised of columns of cells
Adjacent columns receive stimulation from same area of the retina
Map of retina created within visual cortex

74
Q

What is the critical window

A

Period of time during postnatal development identified as being when the nervous system must obtain specific experiences to develop properly

75
Q

What structures does visual stimulation create or strengthen

A

Strengthens synapses and stimulates axon growth

76
Q

What happens to unused synapses

A

They are lost and cannot be reformed

77
Q

What is the evidence for critical Windows

A

Hubel & Weisel (kittens)

Monocular deprivation

78
Q

What happens during the critical window when further visual development occurs

A

Dendrites and synapses from the light-stimulated eye take up more territory in the visual cortex
Axons then compete for target cells in the visual cortex

79
Q

What happens during habituation

A

1) with repeated stimulus the Ca2+ channels in the presynaptic neurones become less responsive to the changes in voltage associated with action potentials
2) fewer Ca2+ ions enter the presynaptic neurone
3) less neurotransmitter is released
4) fewer Na+ channels are opened in the postsynaptic neurone, so there is less depolarisation of the membrane
5) an action potential is not generated in the post synaptic membrane
6) the Gill muscle does not contract and the Gill is not withdrawn

80
Q

Define pure research

A

Basic investigation into aspects of biochemistry, physiology and anatomy

81
Q

Define basic research

A

Done simply to gain knowledge

82
Q

Define applied research

A

Done with intent to use the results practically

83
Q

What percentage if any aka used in research are rats, mice and other rodents

A

85%

84
Q

What are the alternatives to animal testing

A

In vitro techniques
In silico techniques
Epidemiology

85
Q

How do characteristics form under nature

A

Develop solely under the influence of genes with little influence from our environment or learning

86
Q

How do characteristics develop under Nature

A

Characteristics are learnt or are heavily influenced by the environment

87
Q

How is neurotransmitter removed from the synaptic cleft

A

Neurotransmitter either broken down enzymes or reabsorbed into the presynaptic neurone
Transporters in the presynaptic membrane take up the neurotransmitter serotonin from the synapse
The neurotransmitter is then repackaged into synaptic vesicles

88
Q

what effect does ecstasy have on serotonin

A

It blocks transporter proteins preventing re-uptake of serotonin
The concentration of ecstasy in synapses will increase
It continually stimulates the pleasure pathways of the brain

89
Q

How does little dopamine contribute to Parkinson’s Disease

A

The axons of neurones located in the basal ganglia which secrete dopamine into the motor cortex die

90
Q

what are 3 symptoms of Parkinson’s

A

stiffness of muscles
tremor of muscles
poor balance

91
Q

List the methods of treatment for Parkinson’s

A 
Selegiline
L-Dopa
Agonists
Gene therapy
Cell therapy
Surgical Techniques
92
Q

What is Selegiline and how does it help treat Parkinson’s

A

it slows the loss of dopamine from the brain by inhibiting the enzyme monoamine oxidase which breaks down dopamine in the brain

93
Q

what is L-Dopa and how does it help treat Parkinson’s

A

dopamine cannot be taken up from the blood stream directly

L-Dopa is converted into Dopamine in the brain

94
Q

What does ecstasy do

A

It blocks transporter proteins preventing reuptake of the neurotransmitter serotonin
When ecstasy is present, the conc of serotonin will increase in the synapses
It contralto stimulate the pleasure pathways of the brain through increasing serotonin levels

95
Q

What are Agonists and how can they help treat Parkinson’s

A

drugs that activate the dopamine receptor directly, mimicking the role of dopamine

96
Q

How can gene therapy be used to treat Parkinson’s

A

uses genes that code for proteins that increase dopamine production and that promote the growth and survival of nerve cells are inserted into the brain

97
Q

How can cell therapy be used to treat Parkinson’s

A

proteins themselves which increase dopamine production are injected into the brain

98
Q

How can surgical techniques be used to treat Parkinson’s

A

Deep Brain Stimulation treats Parkinson’s symptoms by implanting electrodes into areas of the brain

99
Q

What is depression

A

a multifactoral disease linked to low serotonin levels

100
Q

How is depression treated

A

drugs used to inhibit the re uptake of serotonin from synaptic clefts - Selective Serotonin Re-uptake Inhibitors
Prozac maintains higher levels of Serotonin

101
Q

Define genome

A

all the DNA of an organism

102
Q

Define Single-Nucleotide Polymorphisms

A

DNA sequence variation that involves a change in a single nucelotide

103
Q

What is junk DNA

A

non-coding sequences which make up 50% of the human genome

104
Q

What is the Genetic Information Non-Discrimination Act 2003

A

prohibits the use of genetic information by insurers or employees

105
Q

What is a candidate gene

A

a gene that may cause a particular disease

106
Q

What is a drug target

A

specific molecule that a drug interacts with to bring about its effect

107
Q

How is it hoped that the human genome project will improve preventative medicine and drug treatment

A

May help doctors to prescribe the correct drug

Allows for changes in lifestyle

108
Q

What are 3 ethical issues associated with the Human Genome Project

A

Should insurers have access to the information?
Confidentiality issues
Discrimination in employment

109
Q

How are bacteria genetically modified to produce insulin

A

1) the desired gene is located and isolated
2) insulin is inserted into a bacterial plasmid
3) reinsert the plasmid into a bacterium
4) culture the bacteria to cause them to asexually produce

110
Q

How are micro-organisms genetically modified

A

1) restriction enzymes are used to cut the plasmids at a specific DNA sequence and the gene of interest from chromosomes
2) the gene is amplified using PCR with DNA Polymerase
3) Ligation of the transgene and the plasmid occurs with the enzyme ligase
4) plasmid is inserted back into the bacteria
5) bacteria multiply in a fermenter

111
Q

how are plants genetically modified

A

GM crops have the potential to mass produce medicines and chemicals cheaply and efficiently
Known as Micropropagation - cultured in agar

112
Q

What are the methods used to insert foreign genes into a plant

A

Use a bacterium
Use a particle gun
Use a virus

113
Q

What are marker genes

A

they identify which cells have taken up the desired gene

114
Q

What techniques can be used to introduce genes into animals

A

liposomes in gene therapy
injecting DNA directly into the nucleus of fertilised genes
using a retrovirus

115
Q

What is ‘Pharming’

A

use of GMOs to produce therapeutic proteins and vaccines

116
Q

What are some of the concerns with GMO

A

Antibiotic resistance
Harmful products
Transfer of viruses from animals to humans

117
Q

What are the environmental issues associated with GMO

A

transfer of genes to non-GMO plants via cross pollination

Increased use of chemicals to control resistant weeds and insects

118
Q

What are the ownership issues associated with GMO

A

traditional yields are more expensive

GMO seeds are patented and only grown under a license therefore expensive

Biology Topic 5 (2 decks)

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