Cells and microscopy

Question 1

nucleus function

Answer 1

• contains genetic information (DNA)
• controls activities of cells

Question 2

mitochondria function

Answer 2

site of aerobic respiration which releases energy for the cell

Question 3

ribosome function

Answer 3

carries out protein synthesis

Question 4

cytoplasm function

Answer 4

jelly-like substance where most chemical reactions occur

Question 5

cell membrane function

Answer 5

semi-permeable membrane that controls the movement of substances into and out of the cell

Question 6

cell wall function

Answer 6

rigid outer wall of plant cells that strengthens + supports cell

Question 7

chloroplast function

Answer 7

contains chlorophyll which absorbs light for photosynthesis

Question 8

permanent vacuole

Answer 8

contains cell sap to keep the cell rigid + stores water

Question 9

image definition

Answer 9

image that we see when we look down the microscope

Question 10

magnification definition

Answer 10

how many times larger the image is than the object

Question 11

what are antiseptics used/applied for?

Answer 11

applied to living skin or tissue to prevent infection. They cause little or no harm to living cells + tissues but kill the micro-organisms that could cause disease or infections.

Question 12

what are disinfectants used/applied for?

Answer 12

Applied to surfaces, equipment or other non-living objects. They will cause harm to living cells + tissues as well as killing the micro-organisms present.

Question 13

What is the inhibition zone?

Answer 13

The area where no bacteria are found growing. They can also be used to see how effective different antibiotics are

Question 14

What is cell differentiation?

Answer 14

the process by which a cell changes to become specialised for its job

Question 15

Name the examples of specialised cells

Answer 15

• sperm cells ~ reproduction
• nerve cells ~ rapid signalling
• muscle cells ~ contraction
• root hair cells ~ absorbing water + minerals
• Phloem + xylem cells ~ transporting substances

Question 16

What are Eukaryotic cells?

Answer 16

They are organisms that are made up of Eukaryotic cells. Their cells are complex and include all animal + plant cells

Question 17

What are prokaryotic cells?

Answer 17

It is a prokaryotic cell. They are smaller and simpler, e.g. bacteria is a prokaryotic cell

Question 18

What are 2 differences between prokaryotic cells and eukaryotic cells?

Answer 18

• eukaryotic cells have a nucleus and prokaryotic do not
• prokaryotic cells contain plasmids and eukaryotic do not

Question 19

name 5 sub cellular structures that both plant and animal cells have

Answer 19

• plasma membrane
• mitochondria
• nucleus
• ribosomes
• cytoplasm

Question 20

what three things do plant cells have that animals don’t?

Answer 20

• chloroplasts
• cell wall
• vacuoles

Question 21

what type of organisms are bacteria - prokaryotes or eukaryotes?

Answer 21

prokaryotes

Question 22

what gives a higher resolution - light microscope or electron microscope?

Answer 22

electron microscope

Question 23

Give three ways in which a sperm cell is adapted for moving to an egg cell

Answer 23

• long tail and streamlined head to help it move towards towards the egg
• there is a lot of mitochondria in the cell to provide the energy needed
• carries enzymes in its head to digest through the egg cell membrane

Question 24

what are chromosones

Answer 24

structures in cell that contain genetic material (DNA)

Question 25

define the term cell cycle

Answer 25

a series of stages in the life cycle of a cell

Question 26

what is the name of the process by which bacteria divide?

Answer 26

binary fission

Question 27

what is the maximum temperature that microorganisms should be grown in a school lab?

Answer 27

25C

Question 28

name three substances that can diffuse through cell membranes

Answer 28

carbon dioxide, oxygen and urea

Question 29

explain how leaves are adapted to maximise the amount of carbon dioxide that gets in their cells

Answer 29

They are thin and flat so that carbon dioxide has a shorter distance to diffuse and the diffusion therefore occurs at a faster rate.

Question 30

tail of a sperm cell function

Answer 30

enables sperm to move

Question 31

acrosome function (sperm cell)

Answer 31

helps the sperm to penetrate an egg

Question 32

why do muscle cells contain many mitochondria

Answer 32

to provide energy for muscle contraction

Question 33

xylem function

Answer 33

transports water and minerals

Question 34

phloem function

Answer 34

transports sugar and amino acids in dissolved water

Question 35

epidermal tissue function

Answer 35

covers plant