Variation and natural selection

Question 1

define variation

Answer 1

The differences between individuals belonging to the same species

Question 2

define species

Answer 2

A group of organisms with similar features that can breed together to produce fertile offspring

Question 3

5 identifiers for variation

Answer 3

colour
size/width/length
area
patterns
shape

Question 4

histogram for?

Answer 4

variation caused by gene (eg- blood group, hair colour etc)

Question 5

bar graph for?

Answer 5

variation caused by genes & environment(eg- finger length)

Question 6

organisms of the same species have the same number of ______________?

Answer 6

chromosomes

Question 7

scientific name first word –>

Answer 7

genous

Question 8

scientific name middle word –>

Answer 8

species

Question 9

scientific name last word (sometimes not there) –>

Answer 9

subspecies

Question 10

what is a hybrid

Answer 10

a hybrid is a cross of individuals from two different species resulting in a sterile offspring

Question 11

explain natural selection with an example

Answer 11

1.variation
2.competition
3.adaptation
4.selection pressure
5. survival of the fittest
6. inheritance
7.evolution

1. black peppered moth, and white peppered moth–> variation
2. compete to survive
3. adapt to the trees and camouflage
4. selection pressure with industrialisation
   5.survival of the black peppered moths who camouflage with the dark tree trunks covered in smog
5. increase in the number of black peppered moths as the white ones die
6. evolution

Question 12

How does the environment play a role in natural selection?

Answer 12

organisms adapt to what would suit their habitat the best therefore whether a feature is advantageous is determined by the environment around them thus defining what genes are passed on and what aren’t

Question 13

what are the two types of selection

Answer 13

natural selection and artificial selecation

Question 14

define competition

Answer 14

members of a population fight for food, they will be killed by predators, die of disease/ lack of enough food

Question 15

define adaptation

Answer 15

certain variations that allow individuals to be better adapted to their habitat

Question 16

define selection pressure

Answer 16

caused by change in habitat: drought/flood/rain/temperature change/ volcanic eruption

Question 17

define survival of the fittest

Answer 17

better adapted individuals will have a better chance of surviving, breeding and having offspring

Question 18

define inheritance

Answer 18

offspring will inherit the genes and alleles which cause them to have variations required to adapt to have a greater fitness for their habitat

Question 19

define evolution

Answer 19

Over generations and tens of thousands of years a species may change to have individuals with very different characteristics than the original species

Question 20

define genetic differences

Answer 20

differences in genes based on dominant &recessive alleles or because DNA replication isn’t exact

Question 21

what is meant by “some bacteria have become resistant to antibiotics”

Answer 21

one of the bacteria in a population has a gene that is resistant to antibiotics, once the antibiotics kill all the non resistant genes the bacteria with the resistant gene can multiply and form a population of resistant bacteria like itself

Question 22

Are elephants part of the same of different species?

Answer 22

different:
- Savanna
- Asian
- Forest

Question 23

are dogs part of the same or different species?

Answer 23

same species; different breeds or subspecies