Biology 1

Question 1

What is a genome?

Answer 1

A genome is the complete set of instructions to make an organism and or perform biological processes.

Question 2

What are genes?

Answer 2

Inherited units of information

Question 3

What is DNA and what do chromosomes have to do with it?

Answer 3

Depxynucleic acid and they are the molecules of genetic information. Chromosomes are double strands of tightly wound DNA.

Question 4

What are dominant and recessive genes?

Answer 4

Dominant genes are expressed when they are present, whereas recessive genes are only expressed when paired with another similar gene from the other parent.

Question 5

What is a genotype and what is a phenotype?

Answer 5

Genotype refers to the unique genetic makeup conception, whereas phenotype refers to the observable physical characteristics.

Question 6

What does polygenic mean?

Answer 6

Many genes contribute to a trait

Question 7

What is epigenetics?

Answer 7

Refers to changes in gene expression independent of DNA and results from environmental influences.

Question 8

Explain gene manipulation.

Answer 8

Gene manipulation refers to re-combining different DNA structures. These include knock-out procedures (getting rid of a gene) and knock-in procedures (inserting a new gene).

Question 9

Describe twins

Answer 9

The two types of twins are:
Monozygotic (identical) twins which are genetically identical.
Dizygotic (fraternal) twins which share 50% of their genetic material.

Question 10

What are the three common behavioural genetics methods?

Answer 10

Family studies, adoption studies and twin studies.

Question 11

Explain heritability.

Answer 11

Heritability estimates indicate that intelligence has a strong genetic component. The correlation between identical twins is not perfect, implies a role of the environment and upbringing. Heritability doesn’t measure how much of a trait for one person is affected nor does it indicate how much one gene affects a trait.

Question 12

What are the five core personality components?

Answer 12

• openness to experience
• conscientiousness
• extraversion and introversion
• agreeableness
• neuroticism

Question 13

Explain neurons.

Answer 13

Cells specialised for communication. They can be categorised according to function:
- afferent = receive info from sensory organ
- interneurons = communicate between the afferent and efferent
- efferent = send impulses from CNS to PNS
And type:
- unipolar
- bipolar
- multipolar

Question 14

What do glial cells do?

Answer 14

Provide support for neurons; structure, maintenance and regulation.

Question 15

What are the Nodes of Ranvier?

Answer 15

Spaces between the myelin sheath.

Question 16

What do neurotransmitters result in?

Answer 16

Excitatory messages (depolarise) and inhibitory messages (hyperpolarise)

Question 17

List some neurotransmitters and their function

Answer 17

Acetylcholine: muscular movements, memory
Norepinephrine: arousal, learning, memory, wakefulness, eating
Serotonin: modulates emotion, impulse control, dreaming, eating
Dopamine: reward, motivation, voluntary movement
GABA: inhibits action potentials, anxiety, relaxes muscles

Question 18

What is the action potential regarding neurons?

Answer 18

The change in electrical potential associated with passage of an impulse along the membrane of a muscle cell or nerve cell.

Question 19

Define heritability

Answer 19

How much of a trait or behaviour is due to genetic factors. Expressed as a percentage.