Chapter 1+2 - Cells And Organisation

Question 1

How do you calculate total magnification

Answer 1

Eyepiece lens x objective lens

Question 2

Define the term resolution

Answer 2

Resolution is the ability to distinguish between two separate points in an image

Question 3

What is the role of the nucleus

Answer 3

Contains DNA in the form of chromosomes. Controls the cell

Question 4

What is the role of the cytoplasm in a cell

Answer 4

This is where chemical reactions take place

Question 5

What is the function of the cell membrane

Answer 5

Controls what enters and leaves the cells

Question 6

What is the function of the mitochondria in cells

Answer 6

This is the site of respiration.

Glucose + oxygen –> carbon dioxide + water vapour + ATP energy

Question 7

Definition of magnification

Answer 7

Magnification is how much bigger an image is compared to its actual size. Can be calculated by using IAM triangle

Question 8

Function of the cellulose cell wall

Answer 8

This is the outer layer of plant cells. It is made of cellulose. It gives the plant strength and support

Question 9

Why are ribosomes needed in a cell

Answer 9

Ribosomes are the site (location) where proteins are made

Question 10

What is the function of chloroplasts in plant cells

Answer 10

Traps sunlight energy which is needed for photosynthesis

Question 11

What is diffusion

Answer 11

The movement of particles from a high concentration to a low concentration. No energy is needed

Question 12

How does the concentration effect the rate of diffusion

Answer 12

The higher the difference in concentration the faster the rate is

Question 13

How does the distance effect the diffusion rate

Answer 13

If there is a less distance for the particles to travel

Question 14

What is osmosis

Answer 14

The movement of water molecules from an area of high concentration to an area of low concentration across a partially permeable membrane

Question 15

What happens when an animal cell goes into a dilute solution

Answer 15

There is low concentration of water inside the cell and there is a high concentration of water outside therefore water goes in the cell by osmosis across a partially permeable membrane causing the cell to expand and burst this is known as lysis

Question 16

What happens when an animal cell goes into concentrated solution

Answer 16

There is low concentration of water outside the cell and there is a high concentration of water inside therefore water leaves the cell by osmosis across a partially permeable membrane and as a result the cell has shrunk and shrivelled. This is known as crenated (lack of water)

Question 17

IAM triangle

Answer 17

Image, actual size, magnification

Question 18

Permanent vacuole

Answer 18

A space in the cytoplasm filled with cell sap

Question 19

Eukaryotic cells

Answer 19

Plant and animal cells which has DNA to form chromosomes

Question 20

Prokaryotic cells

Answer 20

Bacteria is a prokaryotic so they are single-celled living organisms. It does not have a nucleus

Question 21

What happens when a plant cell goes into a dilute solution

Answer 21

There is a high concentration outside the cell and a low concentration inside the cell. Water would move inside the cell by osmosis through a partially permeable membrane causing the cell to expand but not burst. This is process is called turgid

Question 22

What happens when a plant cell goes into concentrated solution

Answer 22

There is a high concentration inside the cell and a low concentration outside so the water leaves the cell by osmosis through a partially permeable membrane causing it to come off the cell wall. This is known as plasmolysis

Question 23

Plasmids

Answer 23

Extra small rings of DNA found in prokaryotic cells

Question 24

Embryonic stem cells

Answer 24

Can develop into almost every cell

Question 25

Undifferentiated cells

Answer 25

A cell that has nit yet become a specialised cell

Question 26

Differentiated cells

Answer 26

A specialised cell

Question 27

Active transport

Answer 27

• Molecules moving from an area of low concentration to an area of high concentration
• It requires ATP energy and carrier proteins in the cell membrane

Question 28

Interphase

Answer 28

• Stage 1 of the cell cycle

- cell increases in size, DNA doubles, organelles increase in numbers

Question 29

Mitosis

Answer 29

• stage 2 of the cell cycle

- chromosomes get pulled to opposite ends of the cell and the nucleus divides

Question 30

Cytokinesis

Answer 30

• stage 3 of the cell cycle

- cytoplasm and cell membrane divide, 2 identical cells are formed

Question 31

Chromosomes

Answer 31

A piece of DNA that carries genes