science unit 2

Question 1

Define fibre.

Answer 1

Tissues of plants

Question 2

Describe two essential roles of plants in the environment.

Answer 2

Produce oxygen and be food

Question 3

What are the function of:

Roots: Stems Leaves Flowers

Answer 3

Roots:
To bring the water into the stem
Stems
To transport the water and minerals
Leaves
Takes carbon dioxide which creates a plants food
Flowers
To attract insects and breed the flowers

Question 4

What is chlorophyll?

Answer 4

The green cells that make plants green

Question 5

Write a sentence using the words osmosis and diffusion to describe what happens when a tea bag and a spoonful of sugar are placed in a cup of hot water.

Answer 5

First the sugar will spread out and slowly disintegrate into the water, next only water will enter in through the teabag as the sugar cannot, the water takes whatever flavour it has, the flavour will then spread around and mix with the water, giving it the tea taste.

Question 6

Describe the processes of photosynthesis and respiration.

Answer 6

Photosynthesis = sun + water + carbon dioxide = sugar & oxygen (sugar is food)
Respiration = cells that turn gases into energy

Question 7

Describe the two different ways plants can reproduce.

Answer 7

Vegetative = growing plants from a parent plant
Pollination = taking pollen from other plants and breeding it with other plants

Question 8

What is pollination?

Answer 8

Pollen from male plants has sperm in them which fertilizes the ovules which become seeds.

Question 9

Identify the reproductive parts of a flower.

Answer 9

A:     ovules
B:	ovary
C:	style
D:	stigma
E:	Pistil
F:	Anther
G:	Stamen
H:	Filament
I:	Sepal
J:	Petal

Question 10

What is the function of the fruit of a plant?

Answer 10

Storing the food of the plant

Question 11

Define germination.

Answer 11

Seeds developing into a new plant

Question 12

Describe two environmental issues that can result from the erosion of soil.

Answer 12

Desertification, hard to grow crops

• pollution, caused by high levels of chemicals in a water system

Question 13

Define pest and provide an example.

Answer 13

A insect that affects human health and crops.

Question 14

Describe three problems that have resulted from the widespread use of chemical controls.

Answer 14

Can kill beneficial insects like bees
Can kill insects that prey on pests
Can be very poisonous and can damage other insects without controlling the pests

Question 15

Describe one difference and one similarity between genetic modification and selective breeding.

Answer 15

Difference = genetic is modifying the actual cells, while breeding is combining two characteristics of a plant

Similarities = makes plants have good characteristics