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Flashcards in Biology Test Deck (30):
1

Give an advantage of an electron microscope

Has a greater resolution and magnification

2

What does resolution mean?

The ability to distinguish between two points

3

Why can some structures in cells only be seen with an electron microscope

They are very small

4

How do we calculate total magnification

Eyepiece lens X objective lens

5

What is the equation for working out actual size?

Image size/ magnification

6

What comes next : milli, micro

Nano

7

If 10 -3 means millimetre what does x10-6 mean?

Micrometre

8

What are all living things made from

Cells

9

What is the job of the cell membrane

To control what goes in and out of the cell

10

What process happens in mitochondria

Aerobic respiration

11

Where in a cell would you find chromosomes

In the nucleus

12

Name two structures present in a plant cell but not in an animal cell.

Chloroplast, vacuole , cell wall

13

What is the job of a cell wall

To support the cell

14

What is the job of chloroplasts

To trap sunlight energy and carry out photosynthesis

15

What is the job of a flagellum in a bacterial cell?

It rotates to propel it along/ move

16

What two types of DNA do bacterial cells have?

Chromosomal DNA and plasmid DNA (circular)

17

What does diploid mean?

Having the full set of chromosomes, 46 in a human

18

Why does a human sperm cell only have 23 chromosomes?

As it will fuse with an egg cell with 23 to make 46 chromosomes.

19

What does haploid mean?

Half the full set of chromosomes I.e. 23 in humans

20

Which cells are haploid?

Gametes/sperm and egg cells

21

Why does an egg cell have a lot of cytoplasm?

To nourish the developing embryo

22

What is the job of a sperm cell?

To swim to and fertilise and egg cell to join their DNA

23

What is an acrosome for in a sperm cell?

Contains enzymes to penetrate the egg cell membrane.

24

Why do sperm cells need a lot of mitochondria?

To make energy to swim

25

Which cells waft mucus along in the airways?

Ciliated epithelial cells

26

Why are bacterial cells described as prokaryotic?

They don't have a nucleus

27

In a cell what do ribosomes do?

Make proteins

28

Why are plant and animal cells described as eukaryotic?

They have a nucleus

29

What are enzymes made of?

Proteins

30

What substances can we describe as being biological catalysts?

Enzymes