Symbiosis

Question 1

Symbiosis

Answer 1

An intimate relationship between organisms of two different species that live in direct contact with one another.
These ecological relationships are the result of millions of years of co-evolution

Question 2

Two types of symbiosis

Answer 2

Parasitism

Mutualism

Question 3

Mutualistic symbiotic relationship

Answer 3

Both partner species involved in the interdependent relationship benefit as a result of coevolution

Question 4

Interdependent relationships

Answer 4

Neither species can survive without the other

Question 5

Coevolution

Answer 5

the process of reciprocal evolutionary change that occurs between pairs of species or among groups of species as they interact with one another.

Question 6

3 types of mutualistic symbiotic relationships

Answer 6

Both organisms provide a service (clownfish and anenomes)
One organism recieves a service and another receives a resource ( flowering plants and bees)
Both organisms receive a resource (human gut microflora and humans)

Question 7

Plants and animals mutualistic symbiotic relationships examples

Answer 7

Honeysuckle and hummingbird hawk moth

Acacia tree and ants

Question 8

Why can’t coral polyps survive in waters deeper than 100m

Answer 8

Requires the algae zooxanthellea to produce carbohydrate for it, zooxanthellea is a type of plant so it must photosynthesise in order to produce the carbohydrate, needs light for photosynthesis which will not reach 100m deep in water.

Question 9

Parasitism

Answer 9

One organism (parasite) will benefit in terms of energy or nutrients, whereas the host will be harmed as it will lose these resources.

Question 10

Do parasites kill the host

Answer 10

It is not beneficial for the parasite to kill the host as they will lose a stable source of nutrition

Question 11

Why cannot parasites survive outside the host

Answer 11

They have a limited metabolism as such they can’t digest food so require another organism to do it for them

Question 12

3 ways parasites are transmitted

Answer 12

Via direct contact, use of a vector or resistant stages

Question 13

Direct contact

Answer 13

Passed from organism to organism by physical contact - eg head lice

Question 14

Release of resistant stages

Answer 14

Able to survive e adverse environmental conditions until they come into contact with a new host
Eg larvae of the cat flea

Question 15

Use of a vector

Answer 15

A vector is an intermediate organism that transports the parasite from one host to another
Mosquitos carrying plasmodium that causes malaria.

Question 16

Two types of parasitic life cycles -

Answer 16

Direct and indirect

Question 17

Direct life cycle

Answer 17

where eggs are shed and pass on to a new member of the
host species. This cycle
involves one species of host and is common amongst parasites such as flea and louse which feed outside of their host.

Question 18

Indirect lifecycle

Answer 18

involve an intermediate (secondary) host species in its life cycle. This host is
required to allow the
parasite to complete their life cycle.

Question 19

Why does a parasite use a secondary host

Answer 19

To complete its lifecycle