Brainscape's Knowledge GenomeTM

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


See full index

Biology - Year 12 > Module 5: Heredity > Flashcards

Module 5: Heredity Flashcards

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

Why is reproduction important?

A

It is a fundamental evolutionary process which has allowed for the continuity of life and species

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

What are the two main types of reproduction?

A

Asexual and sexual

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

What does sexual reproduction involve?

A

Two parents producing unique offspring

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

What occurs in sexual reproduction?

A

The meeting of special sex cells called gametes

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

What is an advantages of sexual reproduction?

A

Provides genetic diversity

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

What is a disadvantage of sexual reproduction?

A

Lots of time and energy required creating vulnerability to predators

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

How many chromosomes do humans have?

A

46 chromosomes arranged in a homologous pair

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

What does diploid mean?

A

2 sets of chromosomes

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

What does haploid mean?

A

1 set of chromosomes

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

What chromosomes do offspring inherit?

A

One set from mum and the other from dad

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

How is a zygote formed?

A

Fusion of haploid gametes

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

What are hermaphrodite?

A

Bisexual animals meaning they have both female and male parts

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

When is hermaphroditism good?

A

For species with low populations or non-mobile species

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

What is a disadvantage of hermaphroditism?

A

Requires a larger amount of energy expenditure

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

Where can fertilisation occur?

A

Externally or internally

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

What is external fertilisation more suited to?

A

Aquatic organisms

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

What is internal fertilisation more suited to?

A

Terrestrial organisms

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

What is done to increase the success of external fertilisation?

A

Synchronisation, mating behaviour and release of a large amount of gametes

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

Does external fertilisation include parental care?

A

No

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

What is an advantage of external fertilisation?

A

Wide dispersal of young

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

What is an example of external fertilisation?

A

Staghorn coral

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

How do Staghorn coral successfully undergo external fertilisation?

A

Shed million of gametes into the sea
Environmental cues help synchronise reproductive cycle
Pheromones also released with gametes to stimulate nearby coral

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

What is the benefit of internal fertilisation?

A

Protects gametes from dehydration and developing young from predators

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

How does reproduction in reptiles occur?

A

Eggs are fertilised internally and then deposited outside

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

What protection do most reptile eggs have?

A

A soft but tough leathery shell

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

What protection do only a few reptile eggs have?

A

Some like turtle eggs have a hard shell

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

Where does courtship take place for birds?

A

In flight or on the ground

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

Where does copulation occur for birds and what is its disadvantage?

A

Takes place on the ground making them vulnerable to predators

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

How do birds copulate?

A

Since male birds do not have a penis they instead rub their cloacas together with the female bird

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

What shell forms around bird eggs?

A

Calcium carbonate shell

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

Do birds show parental care?

A

They incubate their eggs and exhibit parental care after they hatch

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

What are the three subclasses of reproduction for mammals?

A

Monotremes, marsupials and eutherians

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

What are monotremes?

A

Mammals like platypus and echidna that have internal fertilisation and then lay eggs

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

Do monotremes express parental care?

A

Young hatchlings obtain milk from mammary glands

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

What are marsupials?

A

Mammals like kangaroos that develop internally for a short time and continue their embryonic development in a pouch

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

What is the reproduction cycle called in marsupials?

A

Embryonic diapause

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

Why is embryonic diapause beneficial?

A

It is a strategy to increase chances of survival

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

What are etherians?

A

Placental mammals such as humans where embryonic development occurs inside the body in the uterus

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

When does a placenta develop?

A

Once an embryo has implanted into the uterine wall

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

What does a placenta do?

A

Supplies nutrients and oxygen and removes wastes from the baby

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

What is it called when live young are born?

A

Viviparous

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

What is it called when young are born from eggs?

A

Oviparous

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

What is an advantage of eutherian reproduction?

A

Mature live young are born increasing their chance of survival

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

What does reproduction in plants rely on?

A

External agents to carry gametes also known as pollinating agents

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

What are the reproductive organs of plants?

A

Flowers

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

What is the male reproductive system in plants called?

A

Stamen

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

What are the parts of the stamen?

A

The anther and filament

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

What is the anther?

A

Where pollen grains are formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the filament?

A

The stalk that carries the anther

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the female reproductive system called in plants?

A

The carpel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What parts are there to the carpel?

A

Stigma, style and ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is the stigma?

A

The sticky top surface of a flower to which the pollen adheres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the style?

A

It is what joins the stigma to the ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the ovary in plants?

A

Where the ovules are formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is pollination dependent on?

A

Dependent on wind, water and animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are the two types of pollinations?

A

Cross pollination and self pollination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is an advantage of cross pollination?

A

It ensures greater variation in offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is an advantage of self pollination?

A

It requires less energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Which form of pollination is favoured ?

A

Cross pollination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How do plants account for the inefficiency of wind pollination?

A

Lots of pollen is produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is one method plants use to reduce pollen wastage?

A

They use flowers and nectars to attract animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

How does fertilisation occur in plants?

A

Sperm cell by the pollen tube fuses with ovum inside the ovule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Where do fertilised ovule develop in plants?

A

In the ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What does an ovule become in a plant?

A

An ovule containing an embryo becomes a seed and the ovary becomes its fruit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What are the two main types of fruits produced during reproduction in plants?

A

Dry fruits and fleshy fruits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

How do dry fruits increase distribution?

A

They have explosive mechanism and are light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

How do fleshy fruit increase distribuiton?

A

Animals eat them and then discrete the seeds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is germination and when does it occur?

A

It is when a seed starts growing when it is in good conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is a radicle?

A

A young root which grows during germination that absorbs water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What is a plumela?

A

A young stem that develops during germination and grows green leaves for photosynthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What does asexual reproduction involve?

A

One parent required to create genetically identical offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Where is asexual reproduction most common?

A

In unicellular organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What are some advantages of asexual reproduction?

A

Quick reproduction, competitive advantage if in suitable environment, uses less energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is a disadvantage of asexual reproduction?

A

Particularly vulnerable to sudden changes in environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What are vegetative organs?

A

Organs such as bulbs, tubers, rhizomes and suckers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What are perennating organs?

A

Underground organs such as roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What are the benefits of perennating organs?

A

Allow plants to survive harsh conditions and when separated give rise to new plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What are runners in plants?

A

Long, thin, modified stems that grow along the surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What is an example of a plant that uses runners as a method of reproduction?

A

Strawberries where leaves, flowers and roots are produced at nodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What are rhizomes?

A

Underground horizontally modified stems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is an example of a plant which uses rhizomes as a method of reproduction?

A

Ferns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What are suckers?

A

Roots of some plants which produce modified roots known as sprouts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What is an example of a plant that use suckers as a means of reproduction?

A

Blackberry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What are apoximis?

A

Plants that produce offspring from special generative tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What do apoximis create?

A

Gametes or leaf tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What is an example of a plant that uses apoximis as a means of reproduction?

A

Kangaroo grass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What is budding?

A

When an adult organism gives rise to a small bud

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

What does a bud do once reaching a certain size?

A

Separates from the parent and grows into a new individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What are some examples of organisms that undergo budding?

A

Yeast, jellyfish and brain coral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What happens as a bud is forming?

A

The DNA duplicates and then the nucleus divides with one half moving into the bud

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

How long does budding continue for?

A

As long as there is sufficient nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What is an advantage of budding?

A

If there is no change in the environment it will be highly suited to it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

What is a disadvantage of budding?

A

They are not very resistant to change in the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

What is the main method of reproduction for bacteria and protists?

A

Binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What happens during binary fission?

A

Genetic material is replicated and then split in two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

What is an advantage of binary fission?

A

Rapid population growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What is a disadvantage of binary fission?

A

No genetic variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

How does binary fission occur in bacteria?

A

DNA attaches to opposite ends of the cell membrane and a new cell wall is synthesis in the cell cleavage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

How does binary fission occur in protists?

A

Involves mitosis and the formation of a spindle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What are spores?

A

Spores are tiny unicellular reproductive cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

What are spores produced by?

A

Produced by structures known as sporangia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What makes spores different to gametes?

A

They do not have to fuse with a cell to produce an individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

What is the structure of a fungus?

A

Hyphae form the main structure of the fungal body known as mycellium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What are spores developed from?

A

Haploid nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

What is an advantage of spores?

A

Extremely light so can be spread wide by wind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

How do fungus reproduce if conditions are unfavourable?

A

Sexually

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What is the purpose of manipulating reproduction in agriculture?

A

To improve the quality and yield of food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What is reproductive technology?

A

Any use of technology to assist and improve reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What can be done with reproductive technology?

A

Artificial insemination and embryo splitting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What are sex hormones responsible for?

A

The development of reproductive organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What are breeding seasons?

A

Involves periods of female fertility being limited to once or twice a year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

What are continuous breeders?

A

Females that have fertility cycles that repeat throughout the year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

What are the three main sex hormones?

A

Androgens, oestrogens and progestogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

What are androgens?

A

Male hormones that control the development and functioning of male sex organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

What type of androgen is secreted in the testes?

A

Testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

What does testosterone do?

A

Plays a key role in sperm production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What are oestrogens?

A

Female hormones that control the development and functioning of female sex organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

What is the main function of oestrogen?

A

Ovarian functioning and fertility in females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

What are progestogens?

A

Female hormones that play a key role in pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

What is the most common progestogen?

A

Progesterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

What do oestrogen and progesterone regulate?

A

Gamete production in ovaries, preparing the uterus for implantation, menstruation and maintenance of pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

What are the two types of gonadotropic hormones secreted by the pituitary gland?

A

Follicle stimulating hormones (FSH)
Luteinising hormone (LH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What does FSH do?

A

Stimulates the maturation of follicles in ovaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What does LH do?

A

Promotes final maturation of ovarian follicle, ovulation and development of corpus luteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

When do females get there eggs?

A

Female babies are born with all the eggs they will ever produce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

How does an ova mature?

A

It becomes surrounded by a single layer of cells that begin to divive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

How often on average does the ovarian cycle repeat?

A

Every 28 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

How does a follicle mature?

A

Follicle cells secrete fluid pushing eggs to one side of the follicle which then move to the surface creating a bulge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

What is a matured follicle called?

A

Graafian

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

What hormone is produced during the follicular phase?

A

There is a surge in LH production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

What does the surge in LH lead to in the follicular phase?

A

Causes ovulation and stimulates the next phase of the ovarian cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

How long does the luteinising phase last?

A

Around 14 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

When does the luteinising phase begin?

A

After ovulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

What happens during the luteinising phase?

A

The burst follicle enlarges and changes colour building up a yellow protein lutein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

What is the build up of lutein in the follicle called?

A

It is called the corpus luteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

What does the corpus lutuem do?

A

Secretes progesterone preparing the body for pregnancy

137
Q

What starts the menstrual cycle?

A

Day one is menses which is when the lining of the uterus breaks down

138
Q

When does the follicular phase start and end?

A

Starts on the first day of menses and ends at ovulation

139
Q

What occurs during ovulation?

A

An egg is released

140
Q

What does progesterone produced by the corpus luteum do?

A

Prepares the lining in the uterus for implantation

141
Q

What hormones does the placenta produce?

A

Progesterone, oestrogen and HCG

142
Q

What does LH stimulate in males?

A

The production of testestrone

143
Q

What does FSH stimulate in males?

A

The production of a protein to maintain testestrone levels

144
Q

What does the hormone inhibin do in the male reproductive cycle?

A

Reduces levels of FSH in the body

145
Q

Where and how are sperm produced?

A

Produced by meiosis inside sperm tubules in the testes

146
Q

What is the structure of a sperm?

A

Sperm head contains a haploid nucleus and long tail moves side to side

147
Q

How many sperms enter the female reproductive system?

A

Half a million

148
Q

How long can sperm survive in the female reproductive system?

A

For a couple of days

149
Q

How are sperm attracted to the egg?

A

By rheotaxis which is the movement through fluid

150
Q

What are the three layers of the egg a sperm has to get through?

A

Corna radiata, ona pellucida, cell membrane

151
Q

What prevents other sperms from entering the egg after one has already penetrated it?

A

Surface proteins

152
Q

What is a fertilised egg called?

A

A zygote

153
Q

What happens to the corpeus luteum when a zygote implants?

A

It continues to grow and secreting hormones

154
Q

When does the placenta do after three months?

A

It takes over the role of secreting hormones

155
Q

When does the ovarian cycle usually resume after pregnancy?

A

After the mother stops breastfeeding

156
Q

What does the placenta do?

A

Carries oxygen and nutrients from the mother to foetus and removes waste

157
Q

What are the two things that must occur for birth to occur?

A

Uterus contractions and the tissue of the cervix must soften so that it can dilate

158
Q

What hormones initiate labour?

A

Prostaglandins secreted by the uterus wall

159
Q

What does oxytocin promote during labour?

A

Coordinated contractions and softens the cervix

160
Q

What does relaxin do during labour?

A

Further aids in the softening of the cervix

161
Q

What does the decrease of progesterone and oestrogen do during labour?

A

Promotes stronger contractions

162
Q

What is mitosis responsible for?

A

Growth of multicellular organisms, repairing damaged tissue, asexual reproduction and genetic stability

163
Q

What does meiosis result in?

A

Formation of gametes

164
Q

What are the two parts of meiosis?

A

Meiosis 1 - diploid cell divides into haploid cells with half chromosomes
Meiosis 2 - cell divide again resulting in four haploid cells

165
Q

What are the five main phases of the cell cycle?

A

G1 - gap phase for cell growth before DNA replication
S - synthesis during which DNA replicates (interphase)
G2 - second gap phase when enzymes check duplicated chromosomes
Mitosis - division of the nucleus
Cytokinesis - separation of the two cells

166
Q

What are the four phases of mitosis?

A

Prophase, metaphase, anaphase and telophase

167
Q

What occurs during prophase?

A

DNA separates into chromosomes containing two copies of DNA

168
Q

What occurs during metaphase?

A

Chromosomes line up in the centre and spindle fibres attach

169
Q

What occurs during anaphase?

A

Sister chromatids separate to opposite ends of the cell

170
Q

What occurs during telophase?

A

Chromosomes gather on opposite ends of the cell and the nuclei form

171
Q

Where else can DNA be found that is not in the nucleus?

A

In organelles such as mitochondria and chloroplast

172
Q

When do organelles replicate?

A

After cell division they replicate independently

173
Q

Who was the first scientist to identify DNA?

A

Miescher

174
Q

What did Watson and Crick use to construct the DNA model?

A

Chemical and X-ray evidence

175
Q

What is the Watson and Crick DNA model?

A

Two stranded molecules with paired bases twisted into a helix

176
Q

What did crick realise about the backbone?

A

That the sugar phosphate backbone is antiparallel to the other

177
Q

What are the two pairing options of bases?

A

Adenine (A) - Thymine (T)
Guanine (G) - Cytosine (C)

178
Q

What holds the DNA strands together?

A

Weak hydrogen bonds

179
Q

What are the two types of nucleic aicds?

A

DNA and RNA

180
Q

What chemicals are in nucleic acic?

A

Carbon, hydrogen, oxygen, nitrogen and sometimes phosphorus

181
Q

What are nucleic acids?

A

Polymers made from monomers called nucleotides

182
Q

What is a nucleotide made from?

A

Ribose (RNA) or deoxyribose (DNA), phosphorus and nitrogen

183
Q

What is DNA and what does it do?

A

Main chemical in the nucleus that stores genetic info that controls the cells and is responsible for transmitting inherited information

184
Q

What is RNA?

A

Is a nucleic acid found in small amounts in the nucleus and in large amounts in the cytoplasm

185
Q

What is a key difference between RNA and DNA bases?

A

RNA has the base uracile (U) instead of thymine (T)

186
Q

What are the three types of RNA?

A

Messenger RNA - mRNA
Ribosomal RNA - rRNA
Transfer RNA - tRNA

187
Q

What does mRNA do?

A

Carries info from the DNA to the cytoplasm

188
Q

What does rRNA do?

A

Brings mRNA and tRNA together during translation

189
Q

What does tRNA do?

A

Translates mRNA messages into proteins

190
Q

What is the first step of DNA replication?

A

Helicase causes the DNA helix to progressively unwind

191
Q

What is the second step of DNA replication?

A

DNA unzips from the bottom creating a replication fork exposing the nucleotide bases

192
Q

What is the third step of DNA replication?

A

A primer attaches to the DNA and DNA polymerase III adds nucleotides to continue the synthesis

193
Q

What are the two strands of DNA doing?

A

They run antiparallel and have either a 3’ end or 5’end

194
Q

From where are nucleotides always added?

A

From the 3’ end

195
Q

What is the leading strand and how are nucleotides added to it?

A

They end with 3’ end so nucleotides are added in long chains

196
Q

What is the lagging strand and how are nucleotides added to it?

A

They end with 5’ end so nucleotides are added in chunks

197
Q

What are the chunks added to the lagging strand known as?

A

Okazaki fragments

198
Q

What does the enzyme ligase do?

A

Forms one continuous strand of the lagging strand

199
Q

What is the fourth step of DNA replication?

A

Replication errors are identified and corrected by DNA polymerase I

200
Q

What are natural errors in DNA replication known as?

A

Spontaneous mutation

201
Q

What are errors in DNA replication caused by exposure to the environment called?

A

Mutagenic mutations

202
Q

What are environmental factors that cause errors in DNA called?

A

Mutagens

203
Q

What is DNA mismatch repair?

A

When polymerase I recognises mismatched base pairs and replaces them correctly

204
Q

What can be the effects of mutations?

A

They can be harmful, beneficial or have no impact

205
Q

Why is accurate replication of DNA important?

A

As the genes code for proteins that determine the functioning of the cell

206
Q

What are 5 mechanisms to ensure genetic continuity?

A

Consistent replication before cell division
Orderly distribution of chromosomes
Successful fertilisation methods
Methods to ensure embryo survival
Natural selection

207
Q

What are 2 mechanisms for genetic variation?

A

Mutation
Mixing of parental genes

208
Q

What is the DNA like in prokaryotes?

A

Contain a single chromosome in a circular strand called a nucleoid

209
Q

What non-chromosomal DNA do prokaryotes have?

A

One or more small rings of non-chromosomal DNA known as plasmids

210
Q

What do plasmids do?

A

Code for features that are not essential to the survival of the cell

211
Q

What is the structure of the DNA in prokaryotes?

A

Supercoiled and forms loops around a central protein

212
Q

What is non-coding DNA known as?

A

Introns

213
Q

What is coding DNA known as?

A

Exons

214
Q

What is the structure of the DNA in eukaryotes?

A

Is linear and is wrapped around five main proteins known as histones

215
Q

What are polypeptides?

A

Molecules made up of a chain of amino acids

216
Q

What is transcription?

A

Process of creating RNA using RNA polymerase

217
Q

What is the first step of transcription?

A

Part of the DNA unzips and the non-coding strand has the info for the protein

218
Q

What is the second step of transcription?

A

The non-coding strand acts as a template for the mRNA to assemble

219
Q

What is the third step of transcription?

A

The mRNA moves out of the nucleus and to the ribosomes

220
Q

What is translation?

A

The synthesis of the polypeptide sequence from mRNA

221
Q

What is the first step of translation?

A

Ribosomes move along mRNA and temporarily attach to tRNA

222
Q

What is the second step of translation?

A

Amino acids on tRNA are linked by an enzyme forming a polypeptide chain

223
Q

What is the third step of translation?

A

tRNA moves away from mRNA leaving a growing polypeptide chain

224
Q

What is the fourth step of translation?

A

Polypeptide chain is processed and created into the final protien

225
Q

What is the fifth step of translation?

A

mRNA is broken down to be reused

226
Q

What is the shape of tRNA?

A

Clover leaf shape with at one end three unpaired bases called anticodons

227
Q

How do tRNA work?

A

An anticodon attaches itself to its complimentary bases on the mRNA and an amino acid binds with the other end depending on the anticodon

228
Q

What is the analogy for protein synthesis?

A

DNA is the operating system, mRNA is the software, tRNA is the machinery and the protein is the product

229
Q

What is non-coding DNA responsible for?

A

It determines whether or not genes are read depending on how tightly its is wrapped around histones

230
Q

What is phenotype?

A

The physical appearance, structure, behaviour and physiology

231
Q

How can phenotype be influenced?

A

Can be influenced by genetics or factors in the environment

232
Q

What is an example of a phenotype influenced by the environment?

A

Hydrangeas are different colours according the pH of the soil they are in

233
Q

What colour are hydrangea flowers when in acidic soil?

A

Blue

234
Q

What colour are hydrangea flowers when in basic soil?

A

Pink

235
Q

What is the primary structure of proteins?

A

Arranged in linear chains

236
Q

What is the secondary structure of proteins?

A

3D arrangement linked by hydrogen bonds

237
Q

What is the tertiary structure of proteins?

A

More complex 3D arrangements

238
Q

What is the quaternary structure of proteins?

A

2 or more polypeptide chains that are linked

239
Q

What do fibrous proteins do?

A

Form structural components of cells and tissues

240
Q

What is the structure of fibrous proteins?

A

Long and insoluble in water

241
Q

What are some examples of fibrous proteins?

A

Collagen, elsatin, keratin

242
Q

What is the structure of globular proteins?

A

Spherical in shape and compact and soluble in water

243
Q

What is an example of a globular protein?

A

Haemoglobin

244
Q

Where can structural protein be found?

A

In connective tissue like skin, bone and tendons

245
Q

What do enzymes do?

A

They are involved in cellular metabolism and catalyse reactions such as chemical respiration and digestion

246
Q

What do channel proteins do?

A

Regulate the intake and output of chemicals such as sodium ions

247
Q

What do receptor proteins do?

A

Receive signals sent by hormones and neurotransmitter and act as markers allowing the body to recognise itself as self

248
Q

What happens during crossing over?

A

Arms of pair of homologous chromosomes wrap around each other

249
Q

What are the points of crossing over of chromosomes known as?

A

Chiasmata

250
Q

What occurs at the chiasmata?

A

Arms of the chromosome break and exchange material

251
Q

What are punnet squares?

A

A model used to represent inheritance

252
Q

What can punnet squares be used for?

A

To predict possible outcomes

253
Q

What is a test cross used for?

A

To determine the genotype of a phenotypical dominant thing as it can either be homozygous or heterozygous

254
Q

What is a pedigree?

A

Traits expressed in a family over several generations with a minimum of three studied

255
Q

What can a pedigree be used for?

A

To study the heredity patterns in families

256
Q

What is the key usually to a pedigree?

A

Male - square
Female - circle
Trait present - shaded

257
Q

What type of numbers should be assigned to each generation in a pedigree?

A

Roman numerals I, II, III

258
Q

What type of numbers should be assigned to each individual in a generation?

A

Normal numbers 1, 2, 3

259
Q

What makes a zygote female?

A

When an X chromosome is inherited from both parents

260
Q

What makes a zygote male?

A

When an X chromosome from the mum and a y chromosome from the dad is inherited

261
Q

What is sex linkage?

A

When the X and Y code for not only gender

262
Q

Which chromosome X or Y can carry the allele?

A

X chromosome

263
Q

In what gender do recessive disorders occur in more frequently?

A

In males

264
Q

What is it called when an allele is present but not expressed?

A

A carrier

265
Q

What is incomplete dominance?

A

The blending of features of the two alleles expressed

266
Q

What is the notation for incomplete dominance?

A

A letter chosen for the gene and the allele is a subscript in the right top corner

267
Q

What is codominance?

A

When both alleles are expressed creating a new phenotype

268
Q

What is the notation for codominance?

A

Same as incomplete dominance but each allele is written with capital letters

269
Q

What does multi-allelic mean?

A

When there are three or more alleles for a single gene trait

270
Q

What is an example of multi-allelic trait?

A

Human blood type that has three alleles A, B and O

271
Q

What is the dominance of the alleles for human blood?

A

A and B are codominant as markers are produced on RBC and and O is recessive as no markers are produced on RBC

272
Q

What is population genetics?

A

Study of how the gene pool of the population changes over time

273
Q

What is the gene pool?

A

Is the sum total of all the genes and alleles with a population

274
Q

How can allele frequency be measured?

A

Number of copies of allele G in the population/ total copies of the gene G + g in the population

275
Q

What does SNP stand for?

A

Single nucleotide polymorphisms

276
Q

What does SNP refer to?

A

Individuals with different phenotypes

277
Q

Where do most SNPs occur?

A

In the non-coding region hence are not observable

278
Q

Why are SNPs important?

A

They are genetic markers used to distinguish individuals and can be associated with disease and disorder

279
Q

What is genotyping?

A

Involves identifying genetic variation in individuals

280
Q

What is sequencing?

A

Involves finding the exact nucleotide sequence

281
Q

What is the sanger method?

A

A method for DNA sequencing

282
Q

What is the sanger method known as?

A

dideoxy DNA (ddDNA) sequencing

283
Q

What are the steps in the sanger method?

A

Isolate DNA from the cells, undergo the sequencing reaction, sort DNA fragments by length using capillary electrophoresis, analyse results using a computer

284
Q

What is the maxam-gilbert method?

A

A method for DNA sequencing

285
Q

What does the maxam-gildert method involve?

A

The chemical sequencing of DNA strands

286
Q

Why is the maxam-gilbert method not used widely?

A

Due to its complex nature and its hazardous chemicals

287
Q

What is DNA profiling also known as?

A

DNA fingerprint analysis

288
Q

What is DNA profiling used for?

A

To identify and compare individuals by their DNA

289
Q

What is DNA profiling a useful tool for?

A

In forensic investigations and paternity testing

290
Q

What does PCR stand for?

A

Polymerase chain reaction

291
Q

What does PCR do?

A

It increases the amount of DNA for testing

292
Q

What is an ethical consideration of DNA sequencing?

A

Who owns the information once analysed

293
Q

How do you know if an allele is sex linked dominant?

A

If a dominant father has female offspring with dominant traits

294
Q

What base does uracil pair with?

A

Adenine

295
Q

Is an artificially cloned mammal completely genetically identical?

A

No as there is DNA from the donated egg and the donated somatic cell

296
Q

What type of response is sweating?

A

A nervous response

297
Q

What type of response is vasodilation?

A

A nervous response

298
Q

The rupture of an ovarian follicle occurs after a surge in which hormone?

A

Luteinising hormone (LH)

299
Q

What is the response of an Australian plant to a named pathogen?

A

Basket grass responds to Phytophthora cinnamomi which is a fungus by producing hydrogen peroxide, reinforcing the cell wall and plant cell death to limit the spread

300
Q

What is DNA sequencing?

A

Provides the order of bases and pairs

301
Q

What is DNA profiling?

A

Gives information about the relatedness of an organism to other organisms

302
Q

What is the main role of proteins?

A

To provide structure and support for cells

303
Q

What does autosomal mean?

A

That the gene in question is located on one of the numbered chromosomes

304
Q

Why is the process of polypeptide synthesis important?

A

It leads to the correct sequence of amino acids in polypeptides and proteins

305
Q

What is population genetics?

A

The study of genetic variation within a population

306
Q

What factors affect the gene pool?

A

Size population
Mutation
Natural selection
Genetic drift
Diversity of the environment
Migration patterns

307
Q

What was used to compare koalas?

A

Haplotypes

308
Q

What are haplotypes?

A

A group of SNP markers used to compare organisms

309
Q

What is a monogenic disease?

A

A disease from a single gene in all cells of the body

310
Q

What are polymorphisms?

A

When individuals have different phenotypes usually due to mutations

311
Q

What is the newborn screening program?

A

Free genetic testing for newborns for SNPs associated with congenital diseases

312
Q

What are the two main theories for human migration?

A

Multiregional hypothesis
Replacement hypothesis

313
Q

Which theory is correct and what is the evidence?

A

Genetic studies have shown the multiregional hypothesis is correct

314
Q

What are mutagenic agents?

A

Agents which alter DNA and cause mutations

315
Q

What are some examples of chemical mutagens?

A

Ingested chemicals such as alcohol and environmental such as solvents

316
Q

What do chemical mutagens do?

A

They are structurally similar to DNA bases and may be incorporated resulting in incorrect insertion of nucleotides

317
Q

What are natural muatgens?

A

Mutagens present at normal level in the environment

318
Q

What are biological muations?

A

Mutagens which are naturally occurring such as viruses and bacteria

319
Q

What are non-biological mutations?

A

Mutagens which are naturally occurring such as metals

320
Q

What is the arrangement of DNA in prokaryotic cells?

A

Single loop of DNA no nucleus

321
Q

What is the arrangement of DNA in eukaryotic cells?

A

Strands of DNA in a nucleus

322
Q

What is the role of progestrone?

A

Keeps the placenta functioning, maintains the uterine lining, regulates blood sugar levels, stimulates the growth of mammary
glands

323
Q

How does progestrone levels change throughout pregnancy?

A

Normally rises during the first 36–38 weeks of the pregnancy, then fall towards the due date

324
Q

What results in new alleles?

A

Mutation in the DNA gene

325
Q

What does crossing over and and random segregation during meiosis lead to?

A

Creates new combinations of alleles, genetic variation

326
Q

Where can mitochondrial DNA be inherited from?

A

Only females

327
Q

How does mitosis contribute to continuation of species?

A

Mitosis assists the continuity of species by allowing growth and repair as well as asexual reproduction

328
Q

What is independent assortment?

A

Homologous chromosome pairs are separated into daughter cells independently

329
Q

What is random segregation of alleles?

A

During meiosis each parent passes an allele at random to their offspring resulting in a diploid organism

330
Q

How is fertilisation important to the continuation of species?

A

Is essential for sexual reproduction
Involves the genetic input of of two different parents creating genetic diversity

331
Q

Why is genetic diversity important?

A

It is important for natural selection and evolution in changing environments

332
Q

Why is implantation important to the continuation of species?

A

It is important for placental mammals as it allows internal development so that young are born relatively developed

333
Q

Why is hormonal control of pregnancy important to the continuation of species?

A

It ensure that the foetus is born when it has developed sufficiently to allow its survival

334
Q

What does the hormone relaxin do?

A

Allows the expansion of joints and muscles of the mother

335
Q

How many people in a population must have a SNP for it to be counted as an SNP?

A

At least 1% of the population

336
Q

What is the larger structure in DNA?

A

Deoxyribose sugar

337
Q

What is the smaller structure in DNA?

A

Phosphate

338
Q

What is the function of proteins?

A

Are responsible for the functioning of cells as enzymes catalyse reactions

Biology - Year 12 (4 decks)

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