B4 Its a green world

Question 1

Devices used to collect small animals

Answer 1

Nets
Pooters
Pitfall traps

Question 2

The equation for estimating population size

Answer 2

Number in first sample*Number in second sample

/number in second sample previously marked

Question 3

What is distribution?

Answer 3

Recording the location of organisms of one species

Question 4

What is population?

Answer 4

Recording the number of organisms of a particular species in area.

Question 5

What is a community?

Answer 5

When different populations live together in one area, forming a community.

Question 6

Why does collecting data only using sampling techniques give a rough estimate of population size?

Answer 6

When estimating the size of a population using capture techniques, biologists make the assumption that no death, immigration or emigration has occurred with that population. Also only a sample of the location is used.

Question 7

How to be fair and reliable when collecting data?

Sampling techniques

Answer 7

Repeat reading, the more times it’s done / the more sampling techniques you use the more reliable the results would be.

All the reading should use the same equipment to be fair.
Quadrats should be placed randomly

Question 8

What is a habitat?

Answer 8

The location where a species of organisms would live.

Question 9

What are keys used for?

Answer 9

They are used for identifying plants and animals

Question 10

What is an ecosystem?

Answer 10

An ecosystem includes all the living things in an area.

Question 11

What is zonation?

Answer 11

A gradual change in the distribution of species across a habitat.

Question 12

What is zonation caused by?

Answer 12

It can be caused by competition between species.

Question 13

What is an artificial ecosystem?

Answer 13

An ecosystem are those created by humans.
- Fish farms, gardens, forestry plantations.
Humans often control what organisms live in an artificial ecosystem and remove unwanted species.

Question 14

Why are there fewer grass plants as you walk into a woodland?

Answer 14

There would be no resources due to competition between the plants, such as water. Light would be blocked out from the trees

Question 15

Photosynthesis equation.

Answer 15

sunlight
Carbon dioxide + water –> glucose + oxygen
chlorophyll
6CO2 + 6H2O –> C6H12O6 + 6O2

Question 16

How is glucose stored?

Answer 16

Glucose is stored in plants as starch.

1. Starch is converted back into glucose for respiration in plant cells.
2. Starch is insoluble and so will not dissolve in water and flow out out the cells where it is stored
3. Starch does not affect water concentration inside the cells.

Question 17

Why do plants store carbs as starch?

Answer 17

They store it as starch as it is insoluble and will not dissolve and flow out of the cells where it is stored

Question 18

What is cellulose?

Answer 18

Cellulose is used for functions, it is required for the plant to grow. Converted from sugars.

Question 19

What factors will increase rates of photosynthesis?

Answer 19

More carbon dioxide
More light intensity
A warm temperature

Question 20

What is photosynthesis limited by?

Answer 20

Availability of light - provides energy for photosynthesis

Amount of carbon dioxide - often the limiting factor as it is in short supply

A suitable temperature - temperature affects how quickly enzymes work if it is too hot the enzymes will denature.

ALL THE THREE FACTORS MUST BE THERE FOR PHOTOSYNTHESIS TO WORK

Question 21

What is a limiting factor?

Answer 21

The factor which is at the lowest level, limiting the rate of reaction.

Question 22

Why would gardeners not need to mow the lawn during winter?

Answer 22

In winter there are limited levels of light, the temperature would also be too cold. Without the correct factors the grass would be unable to photosynthesis and would not grow.

Question 23

Describe the outer palisade cells.

Answer 23

They are transparent to allow the light through.

Question 24

Describe what a chloroplast is.

Answer 24

Thy contain chlorophyll and other pigments that absorb light energy for photosynthesis.

Question 25

What is the palisade and spongy mesophyll full of?

Answer 25

Chloroplasts

Question 26

Where can chloroplasts be found?

Answer 26

Is the palisade and spongy mesophyll

Question 27

Which part contains the most chloroplasts? | Why?

Answer 27

The upper palisade layer. | It receives the most light.

Question 28

What is there I the spongy mesophyll layer? | Why is it there?

Answer 28

There are airspaces to allow carbon dioxide to diffuse from the stomata to the palisade cells.

Question 29

What do the air spaces do?

Answer 29

The air spaces give the leaf a large surface area to volume ratio.

Question 30

What gives the leaf a large surface area to volume ratio?

Answer 30

The air spaces inside the leaf.

Question 31

What is transparent in the leaf? | Why?

Answer 31

The epidermis is transparent to allow light through.

Question 32

Why are leaves broad and flat?

Answer 32

To increase surface area to allow as much light as possible through.

Question 33

What are the stomata?

Answer 33

Pores in the epidermis

Question 34

What do the stomata do? | And what controls them?

Answer 34

They allow carbon dioxide it and oxygen out. | Guard cells control whether they are open or not.

Question 35

What do the veins in a leaf do?

Answer 35

They contain vascular bundles forming a network supporting the blades of a leaf. They also carry water from the root the leaf and carry soluble sugars away.

Question 36

What carries water and sugars in the leaf?

Answer 36

The veins which contain vascular bundles.

Question 37

Why are leaves thin?

Answer 37

To ensure diffusion path is short for carbon dioxide to diffuse to the mesophyll and palisade cells.

Question 38

What did Van Helmont discover?

Answer 38

He discovered that plants needed to absorb water to grow

Question 39

What is diffusion?

Answer 39

When particles move from an area of high concentration to an area of low concentration till they are evenly spread.

Question 40

What does the rate of diffusion depend on?

Answer 40

It depends on the concentration gradient.

Question 41

Name important molecules leaves and enters cells by diffusion.

Answer 41

Oxygen | Carbon dioxide

Question 42

What can substances diffuse as? | The substance it would have to be to be able to diffuse...

Answer 42

Gases or dissolved particles in a solution

Question 43

How do particles get into a cell?

Answer 43

A particle passes through the the cell membrane.

Question 44

Does the process of diffusion use energy? | Why?

Answer 44

No. | The molecules move spontaneously from regions of high concentration to regions of low concentration.

Question 45

For a molecules to diffuse into a cell, what concentration does outside the cell have to be? Why?

Answer 45

The concentration outside the cell would have to be a higher concentration than inside the cell as diffusion is the movement of particles from a region of higher concentration to a region of lower concentration.

Question 46

Why does diffusion happen?

Answer 46

Due to random, constant movement of particles in a solution. They can move in any direction but far more move from high to low concentration. The net movement of particles would be high to low.

Question 47

What are the factors that can affect the rate of diffusion?

Answer 47

Distance Concentration gradient Surface area

Question 48

How does distance affect the rate of diffusion?

Answer 48

The shorter the distance the particles have to move the quicker the rate of diffusion.

Question 49

How does concentration gradient affect the rate of diffusion?

Answer 49

The greater the distance in concentration between two regions, the faster the rate of diffusion. ex: Lead cells produce oxygen as a waste gas during photosynthesis. There is a build up of oxygen in the lead, giving a steep concentration gradient of oxygen between the inside and outside of the leaf, this leads to rapid diffusion of oxygen out of the leaf.

Question 50

How does surface area affect the rate of diffusion?

Answer 50

The greater the surface area that particles have to diffuse across the quicker the rate of reaction. Gases in a leaf are able to diffuse in and out of cells quickly.