evidence for evolution

Question 1

glist the 4 evidence present for evolution

Answer 1

1. fossil record
2. modification by descent
3. biogeograhy
4. genetics

Question 2

explain how fossil records can be regarded as evidence for evolution

Answer 2

fossil -> strata

Question 3

explain how modification by descent can be regarded as evidence for evolution

Answer 3

evolutionary scientists compared the anatomy of fossils and skeleton of present living organisms and identified the adaption of bones to suit a particular function in each and observed that if organisms had a homologous structure it can be concluded that the organisms share a common ancestor.

Question 4

analagous structures

Answer 4

same function different structure

Question 5

scapula

Answer 5

broader and flater for more attachment of muscles

Question 6

humerus

Answer 6

elongate a limb

Question 7

radius and ulna

Answer 7

elongate limb and/or broaden the limb

Question 8

carpals, metacarpals and phalanges

Answer 8

can be used to broaden and largen the end of the limb

Question 9

explain how biogeography can be regarded as evidence for evolution

Answer 9

Biogeography is the study of the geogrsphical destribution of biological organisms. geogrsphical destribution of biological organisms causes organisms to start mutating by changing their anatomy in order to be able to adapt to new environments.

Question 10

explain how genetics can be regarded as evidence for evolution

Answer 10

species with a similar sequence of genes will be closely related while species with different genes are distantly related.

Question 11

how can we represent genetic relation

Answer 11

phylogenetic trees and evolutionary tree

Question 12

What is variation

Answer 12

difference in geno- and phenotype amongst individuals of a particular species

Question 13

factor contributing to variaton

Answer 13

• meiosis : crossing over and random arrangement
  random fertilisation
• mutation
• random mating

Question 14

crossing over

Answer 14

exchange of genetic material between maternal and paternal chromosomes during prophase 1

Question 15

random arrangement

Answer 15

during metaphase when chromosomes found in equator migrate to opposite ends of the cell in a random way

Question 16

random fertilisation

Answer 16

different genetic makeup of sperm and ova

Question 17

mutation

Answer 17

change in gene which cause change in genotype which causes change in phenotype

Question 18

random mating

Answer 18

random between organisms causes that no offspring is the same

Question 19

discontinuous variation

Answer 19

variation that occurs as discrete classes, and usually controlled by a single or small number of genes, it can be therefore easily eradicated.

Question 20

continuous variation

Answer 20

when phenotype is determined by multiple genes

Question 21

which type of variation is evolutionises easier

Answer 21

discontinuous genes by natural selection