B15 Genetics and Evolution

Question 1

Where did darwin publish his ideas

Answer 1

On the Origin of Species (1859)

Question 2

Why was the theory of evolution by natural selection only gradually accepted

Answer 2

It challenged the Creation Story in the Bible. there was insufficient evidence at the time the theory was published to convince many scientists. the mechanism of inheritance and variation was not known until 50 years after the theory was published.

Question 3

What was Jean Baptise-Lamarks theory

Answer 3

that changes that occur in an organism during its lifetime can be inherited.

Question 4

What did Alfred Russel Wallace do

Answer 4

He independently proposed the theory of evolution by natural selection.

Question 5

What is speciation

Answer 5

Speciation is the development of a new species

Question 6

When does speciation occur

Answer 6

When populations of the same species become so different that they can no longer successfully interbreed to produce fertile offspring

Question 7

What is isolation

Answer 7

Isolation is where populations of a species are separated

Question 8

How can isolation occur

Answer 8

Due to a physical barrier that geographically isolate individuals from the main population. Conditions will be different on each side so they will evolve to have different characteristics due to natural selection. There genetic variation will cause speciation.

Question 9

What is wallace most famous for

Answer 9

He is best known for his work on warning colouration in animals and his theory of speciation.

Question 10

What are fossils

Answer 10

Fossils are the ‘remains’ of organisms from millions of years ago, which are found in rocks.

Question 11

What is extinction

Answer 11

when there are no remaining individuals of a species still alive.

Question 12

How do fossils form

Answer 12

• from parts of organisms that have not decayed because one or more of the conditions needed for decay are absent
• when parts of the organism are replaced by minerals as they decay
• as preserved traces of organisms, such as footprints, burrows and rootlet traces.

Question 13

Why is the fossil record incomplete

Answer 13

Many early forms of life were soft-bodied, which means that they
have left few traces behind. What traces there were have been mainly destroyed by geological activity. This is why scientists cannot be certain about how life began on Earth.

Question 14

What causes extinction

Answer 14

New predators, new diseases, or new more successful competitors. Also changes to the environment over geological time and single catastrophic events, such as massive volcanic eruptions or collisions with asteroids.

Question 15

Why can bacteria evolve rapidly

Answer 15

Because they reproduce at a fast rate

Question 16

What is Clasification

Answer 16

The organisation of living things into groups according to their similarities

Question 17

Explain the Classification of organisms

Answer 17

Traditionally living things have been classified into groups depending on their structure and characteristics in a system.

Question 18

Who developed the system of classification

Answer 18

Carl Linnaeus

Question 19

What did Carl Linnaeus classify living things into

Answer 19

kingdom, phylum, class, order, family, genus and species.

Question 20

How are organisms named

Answer 20

Organisms are named by the binomial system of genus and species.

Question 21

What is in the three domain system by Carl Woese

Answer 21

Archaea, bacteria, eukaryota

Question 22

Archaea

Answer 22

primitive bacteria usually living in extreme environments

Question 23

Bacteria

Answer 23

True bacteria

Question 24

eukaryota

Answer 24

which includes protists, fungi, plants and animals

Question 25

What are evolutionary trees

Answer 25

They are a a method used by scientists to show how they believe organisms are related. They use current classification data for living organisms and fossil data for extinct organisms.