The Biological Approach

Question 1

What are the 3 assumptions for the biological approach?

Answer 1

• Nature not nurture.
• Need to look to biological structures to understand behaviour and processes in the body such as genes, neurochemistry and the nervous system.
• The mind lives in the brain. Thoughts and behaviour have a physical basis.

Question 2

What is a genotype?

Answer 2

Actual set of genes a person has. The genetic make up of DNA.

Question 3

What is a phenotype?

Answer 3

Genotype+ environment. These behavioural characteristics and physical attributes are what determines an individuals ability to reproduce and survive.

Question 4

What is a recessive gene?

Answer 4

A recessive gene only shows up if the individual has two copies of the recessive gene (from both parents).

Question 5

What is a dominant gene?

Answer 5

Always shows even if the individual only has one copy (having two still produces same outcome).

Question 6

What are the three methods of investigating genetic relatedness?

Answer 6

• Twin studies
• Family studies
• Adoption studies

Question 7

What are concordance rates?

Answer 7

The probability of one twin having a characteristic if the other twin has it.

Question 8

What are the two types of twin? What do they mean?

Answer 8

Monozygotic= Twins share 100% of their genes (identical).
Dizygotic= Twins share 50% of their genes (non-identical).

Question 9

Who investigated MZ and DZ twins? What was the study?

Answer 9

Lange (1930) investigated 13 MZ twins and 17 DZ twin pairs. Where one has been in prison, 10 MZ pairs both showed criminal behaviour, 2 of the DZ twin pairs both showed criminal behaviour. Concordance rate = MZ=77% DZ= 12%. Concordance rate isn’t 100% due to behaviour being a phenotype. The sample size is quite small so it may be hard to generalise.

Question 10

What is evolution?

Answer 10

The changes in inherited characteristics in a biological population over successive generations.

Question 11

What is natural selection?

Answer 11

When a species is well adapted to the environment, it will leave more offspring than those who are less adapted.

Question 12

What is a genome lag?

Answer 12

Species have adapted to change and continued to change. Evolution is slow, environments can change overnight. This can result in maladaptive behaviours.