Adaptations, interdependence and competition

遊んで学ぼう

問題に答えてエネルギーを集めたら、釣りや探検を楽しもう。アカウント不要。

教育者の方へ： Adaptations, interdependence and competition（Science、Biology）向けのすぐ使えるレッスンスライド, 復習ノート — レッスンで使うか、学習者がライブゲームとして遊ぶインタラクティブなクラス活動としてトピックを実施できます。

レッスンノート

Levels of Organisation in an Ecosystem

An individual organism is a single member of a species.
A population is a group of organisms of the same species living in the same place at the same time.
A community includes all of the populations of different species living and interacting in the same area at the same time.
An ecosystem is the interaction between a community (the living, biotic part) and the non-living (abiotic) parts of the environment.
Ecosystems can vary greatly in size and scale: a small ecosystem might be a garden pond, while a large ecosystem might be the whole of Antarctica.

Competition

Competition occurs when organisms need the same resource to survive and reproduce, but the resource is limited.
Intraspecific competition is competition between members of the same species.
Interspecific competition is competition between members of different species.
Plants compete for light, space, water and mineral ions from the soil.
Animals compete for food, mates and territory.

Interspecific competition

Interdependence

Within a community, each species depends on other species for food, shelter, pollination, seed dispersal and more.
If one species is removed, it can affect the whole community; this is called interdependence.
A stable community is one where all the species and environmental factors are in balance so that population sizes remain fairly constant.
A food web shows the interdependence of organisms.
If the population of one species changes, it can have knock-on effects on other species in the community.

A food web shows the interdependence of organisms

Abiotic Factors

Abiotic means non-living; an abiotic factor is a non-living factor in the environment.
Abiotic factors that can affect a community include light intensity, temperature, moisture levels, soil pH and mineral content, wind intensity and direction, carbon dioxide levels (for plants) and oxygen levels (for aquatic animals).
Changes in abiotic factors can affect the size and distribution of populations.
For example, lichen are very sensitive to air pollution and cannot grow if sulphur dioxide concentration gets too high.
When interpreting graphs or tables, reference specific figures from the data to support your answer.

Biotic Factors

Biotic means living; a biotic factor is a living factor in the environment.
Biotic factors that can affect a community include availability of food, new predators arriving, new pathogens, and one species outcompeting another so numbers are no longer sufficient to breed.
For example, if grey squirrels are introduced to a habitat occupied by red squirrels, the grey squirrels may outcompete the red squirrels for the same resources, causing the red squirrel population to decrease.
Biotic factors such as competition, predation and disease can change the size and distribution of populations.

Adaptations

Organisms have features (adaptations) that enable them to survive in the conditions in which they normally live.
Adaptations may be structural (e.g. body shape, fur, blubber), behavioural (e.g. being active at cooler times of day) or functional (e.g. kidneys producing concentrated urine).
Animals in cold regions often have a small surface area : volume ratio to minimise heat loss, and a thick layer of fat or fur to insulate against the cold.
Animals in desert regions may have a large surface area : volume ratio to aid heat loss (e.g. large ears), produce very concentrated urine, or be active only in the early mornings, late evenings or at night when it is cooler.
A cactus has many structural adaptations to help it survive in the desert.

Camouflage as an adaptation

Extremophiles

Some organisms live in environments that are very extreme, such as at very high or low temperatures, pressures, or high salt concentration.
Organisms that can live in extreme environments are called extremophiles.
An example of a habitat where extremophiles are found is deep-sea volcanic vents, where conditions are extremely hot, under high pressure and there is no sunlight.
Bacteria called chemoautotrophs survive by using inorganic chemicals to obtain energy, rather than using sunlight in photosynthesis.
Other species can then use these bacteria as a source of nutrition – the bacteria are producers in these food chains.

Sampling Organisms

Ecology is the branch of biology that studies the abundance and distribution of species, and their interactions with each other and their environment.
Sampling involves assessing multiple small areas within a larger habitat and using these results to represent the habitat as a whole.
Quadrats are square frames (e.g. 0.25 m² or 1 m²) placed on the ground; the organisms within them are recorded. They are useful for investigating species that do not move around, such as plants or sessile animals.
Quadrats must be laid randomly to avoid sampling bias; this can be done by converting the area into a grid and using a random number generator to pick sample points.
A belt transect involves laying out a measuring tape in a straight line and placing quadrats at regular intervals along the tape to record abundance of each species.
A line transect involves recording the identity of organisms that touch the line at equal distances along the tape; this only measures which species are present, not their abundance.
When completing an ecological study, ensure data is random and representative by selecting quadrat positions randomly and taking a minimum of 10 readings in each survey area.

スライド

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

登録 — 無料ログイン

練習問題

無料プレビュー — 62問中8問。すべて見るには登録を。

1.Which term describes a group of organisms of the same species living in the same place at the same time?
Easy
- ACommunity
- BPopulation
- CEcosystem
- DHabitat
2.Which term describes all of the populations of different species living and interacting in the same area?
Easy
- APopulation
- BEcosystem
- CCommunity
- DHabitat
3.An ecosystem is defined as all the biotic factors and all the abiotic factors that interact within an area at one time.
Easy
True or false?
4.Which order shows the levels of organisation in an ecosystem from lowest to highest?
Easy
- ACommunity, population, organism
- BCommunity, organism, population
- COrganism, community, population
- DOrganism, population, community
5.Which of the following is an abiotic factor?
Medium
- ACompetition
- BPredation
- CDisease
- DWater availability
6.Which of the following are abiotic factors that can affect a community? (select all that apply)
Medium
- ALight intensity
- BTemperature
- CAvailability of food
- DNew predators arriving
- ESoil pH
7.Which term describes a species from one country that is now living in another country?
Medium
- APathogenic
- BNon-pathogenic
- CIndigenous
- DNon-indigenous
8.In a mutualistic relationship, one organism benefits and the other is harmed.
Easy
True or false?

もっと問題

9.Match each key term to its correct definition.
Medium
- Population
- Community
- Ecosystem
- Habitat
- All the populations living in the same area at the same time
- The place where an organism lives
- A group of organisms of the same species living in the same place at the same time
- All the biotic factors and all the abiotic factors that interact within an area at one time
10.Which of the following is a biotic factor?
Medium
- ALight intensity
- BSoil pH
- CCompetition
- DWind intensity
11.A stable community is one where all the species and environmental factors are in balance so that population sizes remain fairly constant.
Medium
True or false?
12.Which of the following is a behavioural adaptation?
Medium
- AA thick layer of blubber in a seal
- BLarge ears in an African elephant
- CBeing active only at night when it is cooler
- DKidneys that produce very concentrated urine
13.Which of the following are structural adaptations of animals to cold regions? (select all that apply)
Medium
- AA small surface area : volume ratio
- BA thick layer of fat (blubber)
- CProducing very concentrated urine
- DA thick layer of fur
- EBeing active only at night
14.A student counts the number of lichens in quadrats placed on the north, east, south and west sides of tree trunks. Why should the quadrats be placed randomly within the area being studied?
Medium
- ATo make the quadrats easier to see
- BTo avoid sampling bias
- CTo increase the size of the quadrats
- DTo make sure only one species is counted
15.Place the levels of organisation in an ecosystem in order from lowest to highest.
Medium
- Individual organism
- Population
- Community
- Ecosystem
16.A parasite lives on or in a host species. Which statement best describes a parasitic relationship?
Hard
- ABoth the parasite and the host benefit from the relationship
- BThe parasite benefits and the host also benefits
- CThe parasite gains resources from the host, which gains no benefit and is often harmed
- DThe host gains resources from the parasite, which is harmed
17.Biodiversity considers only the number of different species present in an area.
Medium
True or false?
18.In a woodland, earthworms are eaten by frogs and mice. Sparrows eat earthworms and caterpillars. If the population of earthworms decreases, what is most likely to happen to the population of sparrows?
Hard
- AIt will increase because sparrows will eat more caterpillars
- BIt will decrease slightly because sparrows have another food source to rely on
- CIt will decrease significantly because earthworms are their only food source
- DIt will stay exactly the same because sparrows do not eat earthworms
19.Two grey squirrels compete for acorns in a woodland. A red squirrel moves into the same area and also competes for acorns. Which statement correctly describes the types of competition shown?
Hard
- ABoth examples are interspecific competition
- BBoth examples are intraspecific competition
- CThe grey squirrels competing with each other is interspecific, and the grey squirrel competing with the red squirrel is intraspecific
- DThe grey squirrels competing with each other is intraspecific, and the grey squirrel competing with the red squirrel is interspecific
20.A cactus lives in a desert. Which combination correctly matches each adaptation to its type?
Challenge
- ALarge ears - structural; concentrated urine - functional; night activity - behavioural
- BSpines - behavioural; thick stem - functional; shallow roots - structural
- CWaxy coating - functional; night activity - structural; deep roots - behavioural
- DThick stem - behavioural; spines - functional; waxy coating - structural
21.Organisms adapt in response to need, so an individual can develop a new adaptation during its lifetime if it needs to.
Medium
True or false?
22.Which of the following are resources that plants in a community compete for? (select all that apply)
Hard
- ALight
- BSpace
- CWater
- DMates
- EMineral ions
23.The organisms in a food web are said to be interdependent. Which statement best explains what this means?
Medium
- AEach species depends on other species for food, shelter, pollination and seed dispersal, so a change in one population can affect others
- BAll the organisms in the food web are the same species
- CThe organisms only interact with the abiotic parts of their environment
- DEach species can survive completely independently of the others
24.Resources competed for by plants in a community include which of the following? (select all that apply)
Medium
- ALight
- BWater
- CMineral ions from the soil
- DSpace
- EMates
25.Which of the following are biotic factors that can affect a community? (select all that apply)
Medium
- AAvailability of food
- BThe arrival of a new predator
- CSoil pH
- DThe spread of a new pathogen
- EWind intensity
26.A small surface area to volume ratio helps an animal to minimise heat loss to its surroundings.
Easy
True or false?
27.High biodiversity reduces the dependence of one species on another and makes populations more resilient to sudden environmental impacts or disease.
Medium
True or false?
28.Match each type of adaptation to the correct example.
Medium
- Structural adaptation
- Behavioural adaptation
- Functional adaptation
- Desert animals have kidneys that produce very concentrated urine
- A cactus has spines instead of leaves
- Desert animals are only active in the early morning or at night
29.Match each sampling method to the correct description.
Medium
- Quadrat
- Belt transect
- Line transect
- A square frame placed on the ground in which organisms are counted
- Quadrats are placed at regular intervals along a measuring tape
- The identity of organisms touching a measuring tape is recorded at equal distances
30.Place the stages of using a belt transect to investigate species distribution in the correct order.
Medium
- Lay out a measuring tape in a straight line across the sample area
- Place quadrats at regular intervals along the tape
- Record the abundance of each species within each quadrat
31.Order the levels of organisation in an ecosystem from the smallest to the largest.
Medium
- Individual organism
- Population
- Community
- Ecosystem
32.Lichens were counted in quadrats on the north, east, south and west sides of tree trunks. The mean counts were: north 4.0, east 12.0, south 15.5, west 9.0. Which conclusion is best supported by these data?
Medium
- ALichen abundance is highest on the south side of the trunk and lowest on the north side.
- BLichen abundance is highest on the north side of the trunk and lowest on the south side.
- CLichen abundance is the same on all sides of the trunk.
- DLichen abundance is highest on the east side of the trunk and lowest on the west side.
33.A tapeworm attaches to the intestinal wall of its host and absorbs ready-digested nutrients into its body by diffusion. Why does this harm the host organism?
Medium
- AThe tapeworm takes in nutrients that the host has digested, so less energy and material are available to the host.
- BThe tapeworm produces toxins that poison the host's blood.
- CThe tapeworm blocks the host's intestine so no food can pass through.
- DThe tapeworm removes water from the host, causing dehydration.
34.The populations of voles and mice in a woodland were recorded from 2005 to 2010. In 2007, 60 voles and 20 mice were collected. What is the ratio of voles to mice collected in 2007?
Medium
- A3:1
- B1:3
- C60:1
- D1:60
35.A student measured the body mass of a caterpillar. It was 6.0 g at the start and 7.5 g one week later. Caterpillars convert 10% of the food they eat into body mass. What mass of food did the caterpillar eat during the week?
Medium
- A15 g
- B1.5 g
- C0.15 g
- D150 g
36.In a garden food web, slugs and caterpillars are eaten by the same predators. Slug pellets are used in garden A and kill the slugs. A scientist predicts the number of caterpillars will decrease in garden A. Which reason supports this prediction?
Medium
- AThe predators that ate slugs now eat more caterpillars.
- BCaterpillars compete with slugs for the same food, so fewer slugs means more food for caterpillars.
- CSlug pellets are poisonous to caterpillars.
- DCaterpillars are eaten by slugs.
37.A student investigates the effect of light intensity on the rate of photosynthesis in pondweed by counting oxygen bubbles. Which of the following would improve the reliability of the results? (select all that apply)
Medium
- ARepeat the count at each distance and calculate a mean.
- BKeep the temperature and carbon dioxide concentration the same at each distance.
- CCount the bubbles for a longer period at each distance.
- DChange the distance of the light source during each count.
- EUse a different piece of pondweed for each distance.
38.A student wants to estimate the population of slugs in a garden. Which of the following methods could be used? (select all that apply)
Medium
- APlace quadrats randomly in the garden and count the slugs inside.
- BUse a capture-recapture method, marking and releasing slugs, then recapturing.
- CCount all the slugs in the garden by hand.
- DUse a belt transect across the garden.
- EEstimate the number of slugs from the number eaten by hedgehogs.
39.Plants were grown for 3 weeks at carbon dioxide concentrations ranging from 5% to 30%. The average height of the plants increased as the carbon dioxide concentration increased. Which conclusions can be drawn from these data? (select all that apply)
Medium
- AAs carbon dioxide concentration increases, average plant height increases.
- BAt 30% carbon dioxide, average plant height is greater than at 5%.
- CCarbon dioxide concentration has no effect on plant height.
- DPlants grow taller because carbon dioxide is used in photosynthesis.
- EIncreasing carbon dioxide always makes plants grow taller without limit.
40.A line transect records the identity of organisms that touch the line and can be used to measure the abundance of a species.
Easy
True or false?
41.Give the term for the place where an organism lives.
Medium
42.Complete the sentence about competition between organisms.
Easy
Competition between members of the same species is called ____ competition, while competition between members of different species is called ____ competition.
43.A quadrat is placed on the ground and the number of dandelion plants inside it is counted. The counts from five quadrats are 3, 7, 5, 4 and 6. Calculate the mean number of dandelion plants per quadrat.
Medium
44.Give the term for organisms that can live in extreme environments, such as deep-sea volcanic vents.
Medium
45.Complete the sentence about sampling using a belt transect.
Medium
A ____ is a line along which samples are taken. In a belt transect, quadrats are placed at ____ intervals along the tape.
46.Give the term for the relationship in which bees gain nectar from flowers and the flowers gain help in reproducing.
Medium
47.A field has an area of 800 m². The mean number of female glow-worms in 1 m² is 5. Estimate the number of female glow-worms in the whole field.
Medium
48.The mean number of female glow-worms in 1 m² of a field is 5. The field has a total area of 800 m². Estimate the number of female glow-worms in the whole field.
Medium
49.A student counts the number of lichens in quadrats on the west side of four trees. The counts are 7, 9, 12 and 8. Calculate the mean number of lichens per quadrat on the west side.
Medium
50.A quadrat of area 0.25 m² is used to sample daisies. The mean number of daisies per quadrat is 8. Calculate the mean number of daisies per square metre.
Medium
51.Complete the sentence about using a quadrat.
Medium
To avoid bias when placing quadrats, the sampling points should be chosen at ____.
52.Complete the sentence about measuring distribution along a gradient.
Medium
In a belt transect, quadrats are placed at ____ intervals along a measuring tape.
53.Describe the meaning of the term 'community'.
Medium
54.The organisms in a food web are said to be interdependent. Explain what is meant by this.
Hard
55.Explain why a line transect should not be used to measure the abundance of a particular species.
Hard
56.A tapeworm attaches to its host's intestinal wall and absorbs ready-digested nutrients into its body by diffusion. Suggest why this may cause harm to the host organism.
Challenge
57.Describe the key features of a parasitic relationship.
Hard
58.A quadrat is placed on the ground and the number of dandelion plants inside it is counted. The counts from five quadrats are 3, 7, 5, 4 and 6. Calculate the mean number of dandelion plants per quadrat.
Medium
- A4 plants
- B5 plants
- C6 plants
- D7 plants
59.A field has an area of 800 m². The mean number of female glow-worms in 1 m² is 5. Estimate the number of female glow-worms in the whole field.
Medium
- A3600 glow-worms
- B4400 glow-worms
- C4800 glow-worms
- D4000 glow-worms
60.The mean number of female glow-worms in 1 m² of a field is 5. The field has a total area of 800 m². Estimate the number of female glow-worms in the whole field.
Medium
- A4800
- B4000
- C4400
- D3600
61.A student counts the number of lichens in quadrats on the west side of four trees. The counts are 7, 9, 12 and 8. Calculate the mean number of lichens per quadrat on the west side.
Medium
- A8
- B9
- C11
- D10
62.A quadrat of area 0.25 m² is used to sample daisies. The mean number of daisies per quadrat is 8. Calculate the mean number of daisies per square metre.
Medium
- A38 daisies/m²
- B29 daisies/m²
- C32 daisies/m²
- D35 daisies/m²

フラッシュカード

What is a population?

A group of organisms of the same species living in the same place at the same time.

What is a community?

All of the populations of different species living and interacting in the same area at the same time.

What is an ecosystem?

The interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.

What is a habitat?

The place where an organism lives.

What is interdependence?

Within a community, each species depends on other species for food, shelter, pollination, seed dispersal etc. If one species is removed it can affect the whole community.

What is a stable community?

A community where all the species and environmental factors are in balance so that population sizes remain fairly constant.

What is competition?

When a group of organisms all need the same resource in order to survive and reproduce but there is a limited amount of the resource available.

What is the difference between intraspecific and interspecific competition?

Intraspecific competition is between members of the same species; interspecific competition is between members of different species.

What resources do plants compete for?

Light and space, and water and mineral ions from the soil.

What resources do animals compete for?

Food, mates and territory.

What is an adaptation?

A feature, behaviour, or other characteristic that helps an organism to survive and reproduce in its habitat.

What are the three types of adaptation?

Structural, behavioural and functional.

What is a structural adaptation? Give an example.

A physical feature of an organism's body. For example, the large ears of African elephants help them lose heat.

What is a behavioural adaptation? Give an example.

A way an organism acts that helps it survive. For example, desert animals being active only in the early mornings, late evenings or at night when it is cooler.

What is a functional adaptation? Give an example.

A process inside an organism's body that helps it survive. For example, desert animals have specially adapted kidneys that produce very concentrated urine to retain water.

How are animals adapted to cold regions?

They often have a small surface area : volume ratio to minimise heat loss (e.g. rounded shape of penguins, small ears of the Arctic fox) and a thick layer of fat or fur for insulation.

What is an extremophile?

An organism that can live in extreme environments, such as very high or low temperatures, pressures, or high salt concentration.

What are abiotic factors?

Non-living factors in the environment, such as light intensity, temperature, moisture levels, soil pH and mineral content, wind intensity and direction, carbon dioxide levels for plants, and oxygen levels for aquatic animals.

What are biotic factors?

Living factors in the environment, such as availability of food, new predators arriving, new pathogens, and one species outcompeting another.

What is biodiversity?

The range and variety of different species of organisms within a given area, including species richness and the variation within each species.

Why is high biodiversity important for an ecosystem?

It ensures stability by reducing the dependence of one species on another for food, shelter and maintenance of the physical environment, and makes populations more resilient to sudden environmental impacts or diseases.

What is a quadrat and what is it used for?

A square frame made of wood or wire, used to sample organisms within a defined area. It is useful for investigating species that do not move around, such as plants or sessile animals.

How should quadrats be placed to avoid bias?

They must be laid randomly in the area, for example by converting the sampling area into a grid and using a random number generator to pick sample points.

What is a belt transect and how is it carried out?

A line along which samples are taken. Lay out a measuring tape in a straight line, then place quadrats at regular intervals along the tape and record the abundance of each species within each quadrat.

What is the difference between a belt transect and a line transect?

A belt transect uses quadrats at regular intervals to measure abundance, while a line transect records the identity of organisms that touch the line and only measures which species are present, not their abundance.

Unlock all 62 questions, flashcards & more

無料アカウントを作って、このトピックのすべての問題・スライド・フラッシュカード・復習ノートを見よう。

登録 — 無料ログイン

過去問

このトピックの過去問練習は近日公開。

近日公開