4.6 TRIPLE Theory of evolution, speciation and understanding genetics

Question 1

1. Who is known as the father of genetics?

Answer 1

Gregor Mendel

Question 2

2. Which organism did Mendel do most of his studies on?

Answer 2

Pea plants

Question 3

3. Mendel crossed pea plants to observe the traits that could be seen in the phenotype of the offspring. Name some traits he looked at.

Answer 3

Height, flower colour, pod type

Question 4

4. Mendel used the term ‘hereditary factors’. What do we call these things now?

Answer 4

Genes

Question 5

5. Genes can be dominant or __________

Answer 5

Recessive

Question 6

6. Why was Mendel not listened to at the time he made his findings?

Answer 6

• Lack of DNA evidence at the time

- He was a monk and not a scientist

Question 7

7. How did Mendel’s ideas gradually get accepted?

Answer 7

• In the late 1800’s is was seen that chromosomes behave a certain way during cell division.
• In the early 1900’s it was observed that chromosomes behave in a similar way to Mendel’s ‘inherited factors’ (now called genes).
• In 1953 the structure of DNA was discovered which helped understand how genes work.

Question 8

8. Why did Charles Darwin theory of Natural Selection receive a lot of negative feedback at the time his book came out (1859).

Answer 8

• It went against religious belief at the time
• Evidence about genes and mutation was lacking.
• Not many other studies had been done, so there was a lack of evidence.

Question 9

9. What was Charles Dawin’s book called?

Answer 9

The Origin of Species

Question 10

Whose theory was this: ‘Changed acquired during the lifetime are passed on to offspring’

Answer 10

Lamarck (1744-1829)

Question 11

What is the name of the other scientist who also thought up the theory of Natural Selection alongside Darwin? He was credited with the theory of ‘Speciation’.

Answer 11

Wallace

Question 12

12. Why was Lamarck’s theory rejected?

Answer 12

Experiments did not support his hypothesis. e.g. a body builder does not have more muscular babies.

Question 13

13. The development of multiple species from a single ancestor is called ________

Answer 13

Speciation

Question 14

14. Use the key words to describe speciation:

M, V, G, B, S, A, S, R, G, S

Answer 14

A DNA Mutation leads to Variation in the population. Geographical isolation separates some individuals from the group, they can not longer Breed with the rest of the population. Different Selection pressures act on the groups resulting in different traits being an Advantage, giving some individuals a better chance of Survival, Reproduction, and passing on of Genes. This is Speciation where the members of the separated groups can no longer reproduce and have fertile offspring.

Question 15

What characteristic did Wallace study for his work on Speciation?

Answer 15

Warning colours in animals