Chapter 1 Cells

Question 1

Calculating magnification

Answer 1

Size of image / size of real object

Question 2

Calculating image size

Answer 2

Magnification x size of real object

Question 3

Calculating size of real object

Answer 3

Image size / magnification

Question 4

One advantage of a light microscope

Answer 4

It can magnify up to x2000

Question 5

One advantage of electron microscopes

Answer 5

It can magnify up to x2,000,000

Question 6

Nucleus

Answer 6

Controls all the activities in the cell. They carry green genomes on the chromosomes to control to proteins needing to build or regrow cells.

Question 7

Cytoplasm

Answer 7

When most of the chemical reactions take place.

Question 8

Cell membrane

Answer 8

Controls the passage of substances such as glucose into the cell.

Question 9

Mitochondria

Answer 9

Small structures in the cytoplasm where aerobic respiration takes place, to release energy in the body. They are very small about 1-2um in length.

Question 10

Ribosomes

Answer 10

Where protein synthesis takes place making all the proteins needed in the cell.

Question 11

Cell wall (found in plant cells)

Answer 11

Made from cellulose for support and strength the cell structure.

Question 12

Chloroplast

Answer 12

Found in all green parts of a plant. They are green because they contain chlorophyll. Chlorophyll absorbs light for photosynthesis (process of making food within a plant).

Question 13

A permeant vacuole

Answer 13

This is a space in the cytoplasm filled with cell sap. This is important to keep the cells rigid to support the plant.

Question 14

Eukaryotic cells

Answer 14

All have a membrane, cytoplasm and genetic material enclosed in a nucleus.

Question 15

Prokaryotic cells

Answer 15

Consist of cytoplasm and cell membrane surrounded by a cell wall. The genetic material isn’t like the nucleus but is a loop of just genetic material. A common example of a prokaryotic cell is bacteria. Also outside the cell wall is a flagella which is a tail helping the prokaryotic cell to move around

Question 16

Nerve cells

Answer 16

Nerve cells are specialised cells used for carrying out electrical pulses around an animal cells.

Question 17

Muscle cells

Answer 17

Muscle cells are specialised to relax and contract the muscles

Question 18

Sperm cells

Answer 18

Sperm cells are usually released a long way from the egg so they have

• A long tail the whips side to side to help the sperm move through water
• A large nucleus to carry on the genetic information

Question 19

Root hair cells

Answer 19

You can find root hair cells close to the tips of growing plants. This can catch rain water for growth. Also they have many mitochondria to spread energy around the plant.

Question 20

Phloem cells

Answer 20

This cell is specialised to transport tissue that carries food made by photosynthesis around the body of the plant.

Question 21

Diffusion

Answer 21

The spreading out of gas from a high concentrated zone to a low concentrated zone

Question 22

State a difference between diffusion and osmosis

Answer 22

Diffusion is the movement of particles from a high concentrated area to a low concentrated area. This will be in an open area. Osmosis is a demonstration of what happens with the cell membrane

Question 23

Active transport

Answer 23

Moves substances from a more dilute solution to a more concentrated solution

Question 24

What is active transport used for?

Answer 24

Active transport uses energy from food to give the body energy for respiration