Evolution

Question 1

evolution

Answer 1

Change in the characteristics of a species over many generations

Question 2

Generation

Answer 2

The time between the birth of an individual and when they produce their own offspring

Question 3

Fossil

Answer 3

Any remains, impression or trace of a livining thinking from an earlier geological time

Question 4

Homologous structures

Answer 4

structures that are controlled by some of the same inherited genes

Question 5

Analogous structures

Answer 5

Structures that appear similar or have the same function but are controlled by different genes

Question 6

Comparative anatomy

Answer 6

the investigation of comparing different animals’ structures

Question 7

DNA

Answer 7

Is twisted and supercoiled in chromosomes. Its function is to encode a detailed set of plans for cuilding different cell parts. DNA is found in the nucleus.

Question 8

Distributoin of species

Answer 8

A map of all the places where a species occurs.

Question 9

embryology

Answer 9

The study of the embryos of different species

Question 10

Artificial selection

Answer 10

The process by which people choose to breed particular organisms with desirable features; also known as selective breeding or directed selection.

Question 11

Cross-breeding

Answer 11

Selective breeding by combining a desirable feature of one individual with another in the offspring.

Question 12

Inbreeding

Answer 12

Selective breeding in which closely related individuals are allows to breed

Question 13

Natural selection

Answer 13

The process where an environmental factor acts on a population and results in some organisms having more offspring than others.

Question 14

Selective agent

Answer 14

The environment factor that acts on the population during natural selection.

Question 15

Sexual selection

Answer 15

A special case of natural selection where the environmental factor is the selection of a mate.

Question 16

Variation

Answer 16

Differences in characteristics dues to different genes.

Question 17

Species

Answer 17

Group of organisms that can interbreed to produce fertile offspring under natural conditions.

Question 18

Speciation

Answer 18

The process by which one species splits into two or more separate species

Question 19

Isolation

Answer 19

Keeping interbreeding groups apart by some barrier or mechanism

Question 20

how is a fossil formed

Answer 20

when an organism dies, its body is enclosed in mud, or sand. The soft parts decay but some of the hard parts (skeleton, shell, and seeds) are preserved. The mud or sand eventually becomes rock and the hard parts of the organism are mineralised.

Question 21

how does a fossil become exposed

Answer 21

Fossils are found only if they are exposed by earth movements or erosion.

Question 22

How can some fossils not represent the organism living at that time

Answer 22

Fossils will be formed only in places and at times when conditions are suitable for fossilization. • Only the skeletons, shells and other parts resistant to decay will be too preserved.

Question 23

how can scientists build a picture of organisms living millions of years ago

Answer 23

Very few fossils have been found which show changing stage between different groups of organism
By studying the abundance and the type of fossils in the different strata, it is possible to build up a picture of how the populations of organisms changed over millions of years.

Question 24

evolutoin of organisms

Answer 24

Organisms became more numerous and more diverse, i.e. many more species came into existence. Organisms became more complex. Although very few organisms found as fossils are alive today, there are many basic simulates in the body structure of the fossils and similar organisms living today.

Question 25

adaption

Answer 25

is a gradual matching of an animal to its environment over time. It applies to everything about an animal.

Question 26

Jean Lamark

Answer 26

believed that species evolved because they inherited traits acquired through the over or under use of body parts.

Question 27

Darwin's theory

Answer 27

proposed that evolution took place through natural and sexual selection. Darwin made extensive use of specimens and fossil evidence to explain his theory of evolution, but because DNA and genes had not yet been discovered, he was unable to explain why traits varied within individuals or how they were inherited.

Question 28

List some examples where artificial selection has changed a species

Answer 28

- budgerigar to make blue and yellow | - cow

Question 29

how fossils can provide evidence for changes in the structure of a species over geological time.

Answer 29

Fossils of similar species can be contrasted against one another to convey their evolution. And as well their position in the level of the soil demonstrates their position in history, and demonstrating the animals’ structures in prehistoric times.

Question 30

how artificial selection can alter a species.

Answer 30

The ranging colours and types of budgerigars convey the product and possibility of artificial selection. The blue in some budgerigars originated as a mutation of the gene controlling the green feather colour. All wild budgerigars are green, although occasionally blue ones are born, and sometimes all yellow one are born. This allows for many new features developed in the pet budgerigars.

Question 31

why scientists consider that species with the same basic structure are related.

Answer 31

Because of evolution. The species may have started form the same base unit and keep certain characteristics whilst the evolution through each generation, due to breeding with other animals has allowed to characteristics to the species. However the species have some equal homologous genes

Question 32

List four different selective agents

Answer 32

- Biotic factor ( another living thing) - Predation , - Isolation - Physical factor ( temperature, water, soil nutrients or fire)

Question 33

Insecticides, resistnace, antibiotics

Answer 33

Insecticides: a substances used for killing insects Resistance: inherited ability of a species to withstand chemicals such as pesticides. Antibiotics: chemicals made by organisms such as fungi to defend them against bacteria.

Question 34

ays of determining if two organisms are the same species

Answer 34

If they are interbred than they are fertile - study the animals DNA - identify the similarities in the amino acid arrangement in the proteins they make.

Question 35

List three main steps in the process of speciation

Answer 35

Speciation: the process by which one species splits into two or more separate species. This is responsible for the formation of any new species that appear in the fossil record. Three basic steps for speciation: - Variation: or speciation cannot occur. - Isolation: different groups of the population are prevented by some mechanism from interbreeding. It stops gene flow and differences in a population. - Selection: changes the genotype and prevents the groups breeding (such as a mating call or sterile)

Question 36

four reasons why two very similar animals might not be able to mate

Answer 36

Because of Selection where there have been changes made to precent groups breeding even if they came back together again at some time in the future. • Courtship behaviour : ( animals may develop different breeding songs, displays or rituals) • Breeding seasons : ( animals may breed at a different time of the year) • Sterility : ( animals may breed but the offspring are sterile e.g. mules) • Chemical barriers : sperm may be killed by the chemistry of the female