Chapter 1: Cell Structure and Organisation

Question 1

What are the 2 things that cells described as?

Answer 1

• The basic building blocks of life
• The simplest structural and functional units of life

Question 2

What are the 2 apparatuses that we use to see cells?

Answer 2

Light and electron microscopes

Question 3

How much does a light microscope magnify objects up to?

Answer 3

1000x

Question 4

How much does an electron microscope magnify objects up to?

Answer 4

200 000x

Question 5

What is special about light micrographs?

Answer 5

They can come out as colour images

Question 6

What is special about electron micrographs?

Answer 6

They are black-and-white images but can be artificially colourised.

Question 7

What does the protoplasm contain?

Answer 7

Cell membrane, nucleus and cytoplasm

Question 8

What are the 8 organelles that can be found in cytoplasm?

Answer 8

1. Nucleus
2. Rough Endoplasmic Reticulum (RER)
3. Ribosomes
4. Smooth Endoplasmic Reticulum (SER)
5. Golgi body
6. Mitochondria
7. Chloroplasts
8. Vacuoles

Question 9

Describe all the features of the cell membrane?

Answer 9

1. It surrounds the cytoplasm of the cell
2. It is made up of only lipids and proteins
3. It is a partially permeable membrane

Question 10

What is the function of the cell membrane?

Answer 10

It controls the movement of substances in and out of the cell

Question 11

Describe the features of a cell wall.

Answer 11

1. It encloses the entire plant cell
2. It is made of cellulose
3. It is fully permeable

Question 12

What is the function of a cell wall?

Answer 12

It protects the cell from injury and gives the cell a fixed shape

Question 13

Describe the features of cytoplasm.

Answer 13

1. It is a jelly-like substance that fills the inside of the cell
2. it is enclosed by the cell membrane
3. It contains organelles
4. It is the part of protoplasm between the cell membrane and nucleus

Question 14

What is the function of cytoplasm?

Answer 14

It is the site where most cellular activities happen.

Question 15

Which apparatus can the organelles be seen by?

Answer 15

Electron microscopes

Question 16

Describe the features of the nucleus.

Answer 16

1. It is surrounded by a membrane called the nuclear membrane
2. It contains genetic information in the form of chromosomes

Question 17

What is the function of the nucleus?

Answer 17

It controls cell activities and is essential for cell division

Question 18

What will happen if a cell (except for RBC) does not have a nucleus?

Answer 18

The cell will die as it will be unable to undergo cell division

Question 19

Describe the features of the RER.

Answer 19

1. It consists of a network of flattened spaces lined with a membrane.
2. Its surface appears rough when viewed under the electron microscope as ribosomes are attached to its outer surface.
3. Its outer surface is continuous with the nuclear membrane

Question 20

What is the function of the RER?

Answer 20

It allows the ribosomes to attach to it and it transports proteins made by the ribosomes to the Golgi body for secretion out of cell.

Question 21

Describe the features of ribosomes.

Answer 21

1. They are small, round structures.
2. They are either attached to the RER or lie freely in the cytoplasm
3. Ribosomes lying freely in the cytoplasm make proteins that are used within the cell
4. Ribosomes attached to the RER make proteins that are transported out of the cell

Question 22

What is the function of the ribosomes?

Answer 22

They are needed to synthesise the proteins in the cell.

Question 23

Describe the features of the SER.

Answer 23

1. It does not have ribosomes attached to its membrane.
2. It is more tubular than RER
3. It is connected to the RER

Question 24

What are the functions of the SER?

Answer 24

1. It synthesises substances such as fats and steroids.
2. It is the site for detoxification.

Question 25

Dsescribe the features of the Golgi body.

Answer 25

1. It is shaped like a disc 2. It consists of a stack of flattened spaces surrounded by membranes 3. Vesicles can be seen fusing with one side of the Golgi body and pinching off from the opposite side.

Question 26

What are the functions of the Golgi body?

Answer 26

1. It chemically modifies substances made by the ER 2. It stores and packages these susbtances in vesicles for secretion out of the cell.

Question 27

How are substances made by the ER moved out of the cell?

Answer 27

1. Small vesicles containing substances made by the ER are pinched of from the ER. 2. These vesicles then fuse with the Golgi body and release their contents into the Golgi body. The substances made by the ER may be modified inside the Golgi body 3. Secretory vesicles containing these modified susbtances are pinched off from the Golgi body. Thye then move to the cell membrane 4. The secretory vesicles then fuse with the cell membrane and their contents are released out of the cell.

Question 28

Describe the feature of mitchondria

Answer 28

They are small, oval-shaped organelles

Question 29

What is the function of mitochondria?

Answer 29

Aerobic respiration occurs here.

Question 30

What is aerobic respiration?

Answer 30

During aerobic respiration, food substances are broken down to release energy

Question 31

What can the energy released by the mitchondria be used for?

Answer 31

The energy may used by the cell to perform cell activities such as growth and reproduction.

Question 32

What are the features of chloroplasts?

Answer 32

1. They are oval structures found in plant cells. 2. They contain chlorophyll

Question 33

What is the function of chloroplasts?

Answer 33

They are essential for photosynthesis.

Question 34

Describe the feautres of a vacuole.

Answer 34

It is a fluid-filled space enclosed by a partially permemable membrane.

Question 35

What is the function of a vacuole?

Answer 35

They store substances within a cell.

Question 36

What is the type of the vacuole in plant cells?

Answer 36

Large central vacuole

Question 37

What is special about plant cell vacuoles?

Answer 37

They contain cell sap.

Question 38

What is type of vacuole is in animal cells?

Answer 38

Many small vacuoles

Question 39

What is special about animal cell vacuoles?

Answer 39

1. The vacuoles contain water and food substances. 2. These vacuoles usually exist temporarily.

Question 40

What is the cell structure of a red blood cell?

Answer 40

They have thinner central portion and have a biconcave shape.

Question 41

What are the RBC's adaptations + explanation for these adaptations.

Answer 41

1. It contains haemoglobin which bind to oxygen and transports it around the body 2. Its circular, biconcave shape increase the RBC's surface area-to-volume ratio so that oxygen can diffuse in and out at a higher rate. 3. By lacking a nucleus, it enables the cell to store more haemoglobin for transport of oxygen. 4. It is flexible, allowing it to squeeze through capillaries easily.

Question 42

What are the adaptations of a muscle cell + explanation for adaptation.

Answer 42

1. It is elongated and cylindrical in shape, containing many nuclei and mitchondria. 2. Has more mitchondria to release more energy for the contraction of muscle cell.

Question 43

What are the adaptations of a root hair cell + explanation for adaptations.

Answer 43

Has a long and narrow cellular extension to increase surface area-to-volume ratio to absorb water and mineral salts at a higher rate.