Food chains

Year 7: Ecosystem Homework

Name: _________________Class: __________________Deadline: ___/___ /2018

Colour this picture in when you have finished the booklet.

Energy (arrows) gets transferred up the food chain.1. Match up the keywords to the correct definition.

2. What do the arrows show?

3. Label on the diagram the keywords from above.

Food webs

Interdependence:This is when two organisms depend on each other. E.g. humans depend on bee’s to pollinate crops to grow food for us to eat.Decomposers: are bacteria and fungi that break down dead plants and animals which then releases nutrients back into the soil.

1. Which animal eats which prey?

BioaccumulationIt’s not only energy that transfers along a food chain, some chemicals like insecticides (kills insects) get passed along too.Some insecticides are washed into rivers and end up in the sea.

2. How does this affect the fish and polar bears?

Ecosystems

1. Below draw a diagram to show all these keywords and label it with these keywords.

Ecosystem = where plants and animals are found in a particular location.

Community = organisms living in an ecosystem. (E.g. water plants, microorganisms, insects, fish & fish eating birds.

Habitat = an area where an organism lives. (E.g. pond)

Environment = conditions found in a habitat.

A niche is a particular place or role that organism has with in an ecosystem.2. Give examples of where only a particular organisms lives.

CompetitionThis is where organism has to ‘fight’ for things to survive. 1. Below add to the mind map of what animals and plants compete for.

2. Describe this graph about the number of predators and prey.

What do animals compete for?

What do plants compete for?

Rabbits

3. Name some animals that have a predator-prey relationship. What makes the predator a good predator?

Flowers & pollinationThe stamen is the male reproductive part and contains:

Anther – produces pollen (the male sex cells) Filaments – holds up the anther.

The carpel is the female reproductive part and contains: Stigma - this is sticky to catch grains of pollen Style – holds up the stigma Ovary – contains ovules (the female sex cells)

Wolves

1. Use these words and definitions to label this flower diagram.

2. Draw diagrams in this comic strip to show how insects pollinate plants.Brightly coloured and sweet smelling petals to attract insects.

Often contain nectar, a sweet, sugary fluid for bees to use to make honey.

Smaller amounts of pollen produced.

Pollen is often sticky or spiky and sticks to insects.

Anthers and stigma are held inside the flower so insects can brush against them.

Stigma has a sticky coating, so pollen sticks to it.

FertilisationThis is where the nucleus of the pollen grain joins with the nucleus of the ovule. After fertilisation the ovary develops into the fruit and the ovules become seeds.

1. Put these statements in order and label numbers A,B,C on the diagram to show where this is happening and colour in the diagram.

A: the pollen nucleus moves down the tube.B: the pollen nucleus joins with the ovule nucleus. Fertilisation takes place and a seed will form.C: The tube grows out of the pollen grain and down through the style.

Seed dispersalSometimes on a summer’s day you can see lots of things blowing in the air. Many people think it pollen but pollen grains are tiny and hard to see. You are

probably looking at seeds being moved away from the parent plant. This is known as seed dispersal (spreading).

1. Draw a picture to show how seeds can disperse using descriptions below.

Wind dispersal: e.g. dandelion or sycamore seeds which are light enough to move using the wind.

Animal dispersal: e.g. animals eating fruit and any seeds pass through the plant as dropping without damaging it and can then germinate.

Water dispersal: e.g. coconuts get carried in the sea and get washed up on another island and starts to grow there.

Explosive dispersal: e.g. Peapods burst open when they are ripe, throwing the seeds in all directions.