B1.1 Cell Structures

Question 1

What are the two main types of cell?

Answer 1

Eukaryotic and prokaryotic

Question 2

Where do each of these cell’s contain their genetic material?

Answer 2

Eukaryotic: nucleus
Prokaryotic: floating in the cytoplasm

Question 3

What is the size range of eukaryotic cell?

Answer 3

10 micrometer (um) - 100 micrometer (um)

Question 4

What is the size range of prokaryotic cells?

Answer 4

1 micrometre (um) - 10 micrometer (um)

Question 5

Which sub-cellular structures do ALL eukaryotic cells contain?

Answer 5

Nucleus, cytoplasm, cell membrane, mitochondria

Question 6

Those four are the only structures that the animal cell contains. What is the function of a nucleus? (3)

Answer 6

• Controls the activities of the cell.
• Contains the organism’s genetic material
• Contains instructions to make new cells or organisms

Question 7

What is the function of mitochondrion? (2)

Answer 7

• Where respiration takes place
• Contains the enzymes for respiration

Question 8

What is the function of the cell membrane? (2)

Answer 8

• a selectively permeable barrier that controls what substances pass into and out of the cell
• contain receptor molecules

Question 9

What is and what are the function of the cytoplasm? (2)

Answer 9

• a jellylike substance
• chemical reactions that keep the cell alive happen here

Question 10

Why do plants have extra sub cellular structures unlike animal cells?

Answer 10

They can’t move their whole body from place to place like animals can

Question 11

What extra sub cellular structures does the plant cell contain?

Answer 11

• cell wall
• vacuole
• chloroplast

Question 12

What is the function of the chloroplast? (3)

Answer 12

• only in the green parts of the plant
• contains green chlorophyll
• this chlorophyll transfers energy from the Sun as light- essential for photosynthesis

Question 13

What is the function of the vacuole? (2)

Answer 13

• full of cell sap
• this helps to keep the cell rigid so supporting the plant and keeping it upright

Question 14

What is cell sap?

Answer 14

Watery solution of sugar and salts

Question 15

What is and what are the functions of the cell wall? (2)

Answer 15

• surrounds the cell, made of a tough fibre called cellulose
• the cellulose makes the wall rigid and supports the cell

Question 16

Every single cell of bacteria can carry out the seven life processes. What are they?

Answer 16

-Movement
-Reproduction
-Sensitivity
-Growth
-Respiration
-Excretion
-Nutrition

Question 17

What’s the relative size of bacteria?

Answer 17

Around 1 micrometre (um) in size

Question 18

Interesting fact about bacteria:

Answer 18

Hundreds of thousands of bacteria would fit on a full stop.

Question 19

What are prokaryotes?

Answer 19

Single-celled (uni-cellular) organisms without a nucleus

Question 20

Name a difference between eukaryotic and prokaryotic cells:

Answer 20

Eukaryotic have nucleus whereas prokaryotic don’t

Question 21

How do plant cells remain rigid? (2)

Answer 21

The cell wall surrounding the cell supports it and keeps it rigid. The vacuole also helps as it contains cell sap which keeps the cell rigid, supporting the plant and keeping it upright.

Question 22

Why do plant cells have chloroplasts and animal cells don’t?(2)

Answer 22

Chloroplasts are essential for photosynthesis. Plants undergo photosynthesis to make their own food, animals don’t photosynthesise.

Question 23

Why do leaf cells have chloroplasts and root cells don’t? (2)

Answer 23

Chloroplasts are only found in green areas of the plant such as stem and leaves. These are higher up the plant as they take in the energy provided by the sun for photosynthesis. As roots are underground, they don’t have access to sunlight and therefore don’t require chloroplasts.

Question 24

Suggest why it is important for muscle cells to contain many mitochondria: (1)

Answer 24

In order to provide enough energy for the muscle cells to enable movement.

Question 25

Algae are eukaryotic organisms. They live in water and make their own food using photosynthesis. State and
explain which subcellular features you would expect to find in an algal cell.
(6 marks)

Answer 25

Cell membrane - to allow selected substances into or out of the cell
Cell wall - to provide structure
Chloroplasts - to allow the algal cell to produce its own food via photosynthesis
Cytoplasm - where the cell reactions take place
Mitochondria - to release energy for the algal cells
Nucleus - to control the activities of the algal cells
Vacuole - to keep the cells rigid [each worth 1 mark]

Question 26

Suggest the name of the disease caused by pneumococcal bacteria:

Answer 26

Pneumonia

Question 27

What are two adaptions that the bacterial cell may have? Explain

Answer 27

Flagella- tail like structures that allow the cell to move through liquids
Slime capsule- layer outside cell wall that protects bacterium from drying out, also helps bacteria stick to smooth substances.