1.1.1 - Cell Structure (Organelles' structure and function) Part 5

Question 1

Briefly describe the structure of the rough endoplasmic reticulum.

Answer 1

• Consists of a series of flattened, membrane-boud sacs (cisternae)
• They are studded with ribosomes.

Question 2

Describe the fuction of the nucleus and nucleolus.

Answer 2

• Contains most of the gentic material.
• This contains the instruction for making proteins.
• The nucleolus makes RNA and ribosomes.

Question 3

Briefly describe the structure of the smooth endoplasmic reticulum.

Answer 3

• Consists of a series of flattened, membrane-bound sacs (cisternae).
• They do not have ribosomes.

Question 4

Briefly describe the structure of the nucleus.

Answer 4

• It is the largest organelle.
• Surrounded by the nuclear envelope.
• There are holes in the nuclear envelope called nuclear pores.
• In the centre, there is the nucleolus - a dense, spherical structure.

Question 4

Briefly describe the structure of lysosomes.

Answer 4

Spherical sacs surrounded by a single membrane.

Question 4

Describe the function of chloroplasts.

Answer 4

• Chloroplasts are the site in which photosynthesis takes place.

Question 6

Describe the function of the mitochondria.

Answer 6

• Produces most of the ATP.
• ATP releases energy that drives almost all the cell’s activites.

Question 7

Describe the function of lysosomes.

Answer 7

• They contain powerful digestive enzymes.
• These enzymes break down materials.
• In white blood cells, lysosomes help break down microoraganisms.
• They also help the head of the sperm penetrate the egg.

Question 8

Briefly describe the structure of ribosomes.

Answer 8

• Tiny.
• Free in the cytoplasm or bound to ER.
• Consists of two sub-units.

Question 8

What is this organelle?

Answer 8

Chloroplast

Question 10

Describe the function of the ribosome.

Answer 10

• They are the site for protein synthesis.
• They act as an assembly line where the mRNA is used to assemble proteins from amino acids.

Question 11

What is this organelle?

Answer 11

Mitochondrion

Question 12

Describe the fuction of the smooth ER.

Answer 12

• Smooth ER is involved in making lipids.

Question 13

Briefly describe the structure of chloroplasts.

Answer 13

• Two membranes separated by fluid-filled space.
• Inner membrane contains a network of flattened membrane sacs that look like plates- thylakoids.
• Stack of thylakoids- grana.

Question 15

Briefly describe the structure of the mitochondria.

Answer 15

• Sausage or spherical-shaped.
• Have two membranes separated by a fluid-filled space.
• Inner membrane- folded to form cristae.
• Central part of the mitochondrion- Matrix.

Question 16

Describe the function of the rough ER.

Answer 16

• Rough ER helps transport the proteins made from the ribsomes attached to it.

Question 17

Describe the function of the Golgi apparatus.

Answer 17

• Golgi receives proteins from the ER and modifies them such as adding sugar molecules to them.
• It then packages the proteins into vesicles to be transported to either the cell surface or to be secreted.

Question 18

Briefly describe the structure of the Golgi apparatus.

Answer 18

• A stack of membrane-bound, flattened sacs.