Jan/Feb bio test

Question 1

Name all 5 receptors

Answer 1

Eyes, ears, nose, hands, mouth

Question 2

Name the 2 coordinators

Answer 2

brain, spinal cord

Question 3

name the 2 main effectors

Answer 3

muscles, glands

Question 4

What are reflexes?

Answer 4

special type of nervous impulse which is automatic and is designed to protect you.

Question 5

reflexes- They travel through a ______ _______ in the spine called a ______ ______. This makes them faster than normal impulses.

Answer 5

reflexes- they travel through a third neurone in the spine called a relay neurone. This makes them faster than normal impulses.

Question 6

What are evolutionary trees used to show?

Answer 6

Evolutionary trees show how recently species branched from one another, how closely related different species are, and what different species evolved from.

Question 7

What is natural selection also known as?

Answer 7

Survival of the fittest

Question 8

Explain an example of natural selection to do with moths.

Answer 8

There were white moths that blended in with the white trunks of trees to protect themselves from birds. When the trees changed black, they were spotted more easily and their population went down, whereas black moths’ population went up.

Question 9

Why might a species become extinct?

Answer 9

When they can’t adapt to a changing environment, disease, poaching.

Question 10

The _______ system releases chemical messages called _________.

Answer 10

The endocrine system releases chemical messages called hormones.

Question 11

Give an example of the endocrine system in action

Answer 11

The blood sugar level is monitored by the pancreas, causing hormones to be released and sent to the liver

Question 12

When a new species is discovered, it is given a binomial name. What is a binomial name?

Answer 12

A name with two parts, for example: a tiger = ‘panthera tigris’.

Question 13

How is a binomial name given to a new species?

Answer 13

The first name refers to the genus and the second name refers to the species.

Question 14

Explain speciation

Answer 14

Species that have been geographically isolated may meet again. If they meet again and they cannot breed to produce fertile offspring then the species has changed so much during separation that they are now separate species

Question 15

Genes are made of _____ that codes for certain _________.

Answer 15

Genes are made of DNA that codes for certain characteristics.

Question 16

How many PAIRS of chromosomes are in each nucleus of a human cell?

Answer 16

23 pairs

Question 17

Dominant genes will… (finish the sentence)

Answer 17

Dominant genes will ensure a certain characteristic appears in an individual.

Question 18

When will recessive genes appear?

Answer 18

Recessive genes will only appear when the dominant genes aren’t present.

Question 19

A ______ square is a useful way of working out the _________ of ________ a particular gene.

Answer 19

A Punnett square is a useful way of working out the probability of inheriting a particular gene.

Question 20

A man and a woman want to have a baby. The man (Dd) has polydactyly and the woman (dd) does not. What is the probability that the child will have polydactyly?

Answer 20

There is a 50% chance that the child will have polydactyly. You could use a Punnett square to help next time if you need to.

Question 21

State some negatives of selective breeding:

Answer 21

Reduction in gene pool, pathogens could wipe out the whole species, etc.

Question 22

State some positives of selective breeding:

Answer 22

More money, weaker organisms are wiped out, etc.

Question 23

Genetic engineering is the process of… (finish the sentence)

Answer 23

Genetic engineering is the process of cutting a useful gene from one organism and inserting it into another.

Question 24

What are stem cells?

Answer 24

Stem cells are unspecialised cells that can differentiate into almost any other type of cell, including bone marrow, blood cells, and muscle cells.

Question 25

Why might stem cell treatment be better than an organ transplant?

Answer 25

Less risk of rejection, shorter waiting time because you don't have to wait for an organ donor.

Question 26

Why might an organ transplant be better than stem cell treatment?

Answer 26

Stem cell treatment is very expensive, there is some risk involved with stem cells because the use of them is very new, stem cells are difficult to obtain. 60% of people survive for ten more years after an organ transplant.

Question 27

State some advantages of cloning.

Answer 27

Clone excellent examples of animals, farmers can make more money, you know what features your animals are going to have.

Question 28

State some disadvantages of cloning.

Answer 28

Reduces genetic variation, some people view it as "playing God", requires scientists and special equipment which might be expensive or difficult to acquire.

Question 29

What is the definition of biodiversity?

Answer 29

Biodiversity is the existence of a wide variety of plants and animal species living together in their natural environment.

Question 30

A black spider monkey is considered an endangered/vulnerable animal. Why might this be?

Answer 30

A low population, high risk of extinction, the amount the population has decreased in the last few years. Extras- The black spider monkey specifically has a population of around 250 and has fallen by 30% in the last 45 years, but it isn't high risk enough to be considered critically endangered like amur leopards and mountain gorillas, for example.