8. Adaptation and Environment

Question 1

How is the flea adapted?

Answer 1

• Sharp mouthparts -> Helps break the host’s skin and suck blood
• Flattened body -> Not easily brushed off
• Hard body -> Protection against animals
• Long hind legs -> Helps jump between hosts

Question 2

How is the tapeworm adapted?

Answer 2

1) Suckers and hooks -> Help attach tapeworm to intestine wall
2) Long, flattened body -> Fits inside intestine + large SA for food absorption
3) Many segments -> Produce lots of eggs
4) Thick outer cuticle -> Stops tapeworm being digested
5) No gut -> Tapeworm absorbs digested food

Question 3

How are organisms adapted to extreme environments?

Answer 3

Desert animals - large Surface Area : Volume to lose heat
Arctic animals - small Surface Area : Volume to lose less heat
Thermophilic bacteria - Hot springs, sulphur for respiration, survive in low pH conditions
Acidophile - Hot acidic springs, low respiration rate, live in volcanic vents

Question 4

What is malaria?

Answer 4

A life-threatening disease caused by the single-celled malaria parasite.

Question 5

What type of organism is the malaria parasite?

Answer 5

Single-celled

Question 6

In which organisms does malaria’s life cycle take place?

Answer 6

Partly in animals and partly in mosquitos.

Question 7

Do mosquitos cause malaria?

Answer 7

No, they just pass on the parasite when they bite animals to feed.

Question 8

How many forms does the malaria parasite have and why?

Answer 8

4 - each one is adapted for living in a different place in the animal or mosquito.

Question 9

What are the 4 forms of the malaria parasite?

Answer 9

1) Gametocytes
2) Sporozoites
3) Merozoites
4) Schizonts

Question 10

Describe the life cycle of the malaria parasite.

Answer 10

1) Gametocytes
- Mosquito sucks up blood containing gametocytes
- Gametocytes reproduce sexually
- Gametocytes go to salivary glands + become sporozoites

2) Sporozoites
- Mosquito bites animal + transfers sporozoites to blood
- Sporozoites pass through blood to liver, where they enter liver cells
- Inside cells, sporozoites rapidly divide asexually to produce merozoites

3) Merozoites
- Many merozoites released into blood
- Merozoites invade RBCs
- EITHER 4a or 4b happens

4a) Schizonts
- Merozoite grows + its nucleus divides asexually, producing a cell with many nuclei (schizont)
- Each schizont divides -> Produces many merozoites
- RBC bursts, releasing merozoites and toxins (triggering fever attacks)
- Merozoites each invade a RBC and cycle repeats
(- Infected RBCs usually burst at the same time, resulting in cycles of fever attacks)

4b) Gametocytes Again
- Some merozoites enter sexual reproduction -> Produce gametocytmes
- RBCs containing gametocytes are sucked up by mosquito -> Cycle repeats

Question 11

How is the malaria parasite adapted?

Answer 11

• Merozoites have sticky protein molecules on surface to help them catch a RBC to invade.
• In animals, the parasites are adapted to live inside cells, making it hard for the immune system to detect and destroy them.

Question 12

How can the 4 forms of malaria be remembered?

Answer 12

GAMEs and SPORts or MERingues and SCHnapps

Question 13

What are adaptations?

Answer 13

Characteristics that allow organisms to live in certain environmental conditions.

Question 14

What are the 3 types of adaptation?

Answer 14

• Structural
• Behavioural
• Functional

Question 15

What are structural adaptations?

Answer 15

Features of an organism’s body structure (e.g. shape or colour)

Question 16

Give an example of a structural adaptation.

Answer 16

• Polar bears have white fur for camouflage.
• Whales have a thick layer of blubber for warmth.
• Camels have a large SA:V ratio.

Question 17

What are behavioural adaptations?

Answer 17

The ways in which organisms behave.

Question 18

Give an example of a behavioural adaptation.

Answer 18

Swallows migrate to warmer climates in the winter to avoid the problems of living in cold conditions.

Question 19

What are functional adaptations?

Answer 19

Things that go on inside an organism’s body that can be related to processes like reproduction and metabolism.

Question 20

Give an example of a functional adaptation.

Answer 20

• Brown bears lower their metabolism while they hibernate to conserve energy.
• Desert animals produce very little sweat and small amounts of concentrated urine to conserve water.

Question 21

What are extremophiles?

Answer 21

Microorganisms which are adapted to live in very extreme conditions like hot volcanic vents, salty lakes or at high pressure on the sea bed.

Question 21

Where do fleas live and how do they feed?

Answer 21

• Live in the fur of mammals

* Feed by sucking blood from the host

Question 22

Where do tapeworms live and how do they feed?

Answer 22

• Live in the intestines of mammals and other animals

* Feed by absorbing digested food

Question 23

What do plants compete for?

Answer 23

• Light
• Space
• Water
• Minerals

Question 24

What do animals compete for?

Answer 24

* Space * Food * Water * Mates

Question 25

Who do organisms compete with?

Answer 25

Other species as well as their own species.

Question 26

Give an example of competition between species.

Answer 26

Red and grey squirrels live in the same habitat and eat the same food. The competition means that the red squirrel population is in decline.

Question 27

Give some examples of living factors which affect the environment.

Answer 27

A change in: | 1) The number or types of competitions

Question 28

Give some examples of non-living factors which affect the environment.

Answer 28

A change in: 1) Average temperature 2) Availability of nutrients 3) Amount of light 4) Average rainfall 5) Availability of oxygen and CO2 6) Availability of nesting sites, shelter and habitats

Question 29

What are communities?

Answer 29

Groups of populations of different species that interact with each other.

Question 30

How can environmental changes affect populations?

Answer 30

* Population sizes can increase or decrease | * Distribution of populations can change

Question 31

Give a reason why a population size may increase.

Answer 31

Number of prey may increase -> more food available -> more predators survive and reproduce -> their numbers increase too.

Question 32

Give some reasons why a population size may decrease.

Answer 32

E.g. Number of bees is the US is decreasing and it could be because: 1) Pesticides -> May have negative effect on bees 2) Less food -> Not many nectar-rich plants 3) More disease -> Bees killed by pathogens

Question 34

Give a reason why a population's distribution may change.

Answer 34

Change in temperature may affect where an organism lives.

Question 35

What are the two ways that environmental change can be measured?

Answer 35

* Living indicators | * Non-living indicators

Question 36

What are living indicators?

Answer 36

Organisms that are very sensitive to changes in their environment, which can be studied to see the effect of human activity.

Question 37

How can air pollution be measured using a living indicator?

Answer 37

Lichen are very sensitive to sulphur dioxide. The number and type of lichen in an area show how clean the air is.

Question 38

What happens when raw sewage is released into a river?

Answer 38

1. Bacteria increases. 2. Bacteria uses up the oxygen. 3. Mayfly larvae are sensitive to oxygen. 4. So, if you find mayfly larvae, the river must be clean.

Question 39

What do invertebrates tell us about a river?

Answer 39

1. Some species prefer clean conditions (e.g. mayfly larvae), so they show that the water is clean. 2. Other species are adapted to live in polluted areas (e.g. rat-tailed maggots), so they show that the water is polluted.

Question 40

What are non-living indicators?

Answer 40

Factors such as oxygen levels, temperature and rainfall.

Question 41

What are the four pieces of equipment that scientists use to measure non-living indicators?

Answer 41

1. Satellites -> Temperature of sea surface 2. Automatic weather stations -> Atmospheric temperature 3. Rain gauges -> Rainfall 4. Dissolved oxygen meters -> Concentration of dissolved oxygen in water

Question 42

What are the advantages and disadvantages of looking at living indicators?

Answer 42

ADV • Quick, cheap and easy • Long term because organisms change over a long time DIS • Results can be affected by other factors

Question 43

What are the advantages and disadvantages of looking at non-living indicators?

Answer 43

``` ADV • Reliable, numerical data that is easy to compare • Exact pollutants can be identified DIS • Expensive • Trained workers needed • Only gives a snapshot of conditions ```

Question 44

What is a habitat?

Answer 44

The place where an organism lives (e.g. A playing field)

Question 45

What is the distribution of an organism?

Answer 45

Where an organism is found (e.g. In a part of a playing field)

Question 46

Where an organism is found is affected by...

Answer 46

...environmental factors

Question 47

What are the two ways to study the distribution of an organism?

Answer 47

* Measure how common an organism is in two sample areas and compare them, e.g. using quadrats * Study how distribution changes across an area, e.g. by placing quadrats along a transect These both give quantitive data.

Question 48

What is a quadrat?

Answer 48

A square frame enclosing a known area

Question 49

How can a quadrat be used to compare two sample areas?

Answer 49

1. Place the quadrat at a RANDOM point in the first area (using coordinates and a random number generator) 2. Count all of the organisms (of a species) in the quadrat 3. Repeat 1 and 2 many times 4. Work out the mean amount of organisms per quadrat 5. Repeat 1 to 4 in another sample area 6. Compare the two areas

Question 50

How do you work out the population size of an organism in an area?

Answer 50

1. Find the mean number of organisms per m2 | 2. Multiply the mean by the total area

Question 51

How do you use a transect to study the distribution of organisms along a line?

Answer 51

1. Mark out a line 2. Collect data by: a) Simply counting the organisms along that line b) Placing a quadrat at intervals along the line

Question 52

When collecting environmental need to think about...

Answer 52

1) Reproducibility and repeatability | 2) Validity

Question 53

How can you make your experiment more reproducible?

Answer 53

Use large sample sizes | e.g. Use as many quadrats and transacts as possible. Bigger sample are more representative of the whole population.

Question 54

What does repeatable mean?

Answer 54

That the experiment can be repeated in the same area by the same person, with the same equipment and method, and the results will be the same.

Question 55

What does reproducible mean?

Answer 55

That the experiment can be repeated by another person, or using different equipment and method, and the results will be the same.

Question 56

When can an experiment's results be considered valid?

Answer 56

When they: • Are repeatable • Are reproducible • Answer the original question (while controlling all variables)

Question 57

How can you ensure that a result is valid?

Answer 57

* You just make sure it answers the original question (i.e. Make sure all variables are controlled, except the independent variable). * Also, make sure it is reproducible and repeatable. * Use random sampling.

Question 58

Why must all variable be controlled when comparing the distribution of organisms?

Answer 58

It makes it clear whether the link is correlation or causation.