Chapter 4 - Evolution - Inheritance

Question 1

What are the differences within a species called?

Answer 1

Variation

Question 2

Why can variation come about?

Answer 2

1. Some features can be inherited - that means you get them from your parents
2. Other features are affected by the environment
3. Lots of features are a combination of both

Question 3

Give some examples of inherited variation

Answer 3

~ blood type
~ eye colour
~ Down syndrome

Question 4

Give some examples of both inherited and environmental variation

Answer 4

~ BMI
~ height
~ hair colour
~ skin colour 
~ skin cancer
~ intelligence (IQ)

Question 5

Give some examples of environmental variation

Answer 5

~ accent
~ scars
~ tattoos
~ infectious diseases

Question 6

How does variation come about?

Answer 6

~ sexual reproduction - genetic information exchanged between male and female gametes
~ from the environment affecting the organism - eg. Humans dying hair does not get passed on to the offspring

Question 7

What is Lamarckism?

Answer 7

Environment affecting genetics (not true - apart from radiation)

Question 8

What is continuous variation?

Answer 8

~ normal distribution (bell-shaped)
~ eg. Height
~ mainly environmental
~ range of values (that change gradually) with most people roughly in the middle
~ have to be ordered in certain way (eg. Small —> big)

Question 9

What is discontinuous variation?

Answer 9

~ usually bar graph
~ eg. Eye colour
~ mainly genetic/inherited
~ distinct groups, but some are more common
~ no specific way to order (eg. Blue, brown, green etc)