CELL STRUCTURE AND FUNCTION

Question 1

What is the cell’s function?

Answer 1

Responsible for all the chemical reactions that occur in the body.

Question 2

What is cell specialisation?

Answer 2

Each different type of cell has a special function.

Question 3

What is cell theory?

Answer 3

All organisms are made of cells, which are the basic unit of life and arise from pre-existing cells.

Question 4

What are the main structural parts of a cell?

Answer 4

Cell membrane, Golgi body (appartus), Mitochondria, Cytoskeleton, Nucleus, Nucleolus, Lysosomes, Ribosomes, Endoplasmic Reticulum, and Centrioles.

Question 5

What is the cell membrane

Answer 5

• The outer boundary of the cell.
• Determines which substances get in/out of a cell.
• Made up of a double layer of molecules & associated proteins (phospholipid bilayer)

Question 6

Describe the function of a Golgi Body

Answer 6

• Flattened membranous bags stacked on top of each other.
• Modify proteins and package them into vesicles for secretion from the cell.
• Vesicles are pinched off from the edges of the cell membranes

Question 7

Describe the function of the Mitochondria

Answer 7

• Spherical/elongated structures spread through the cytoplasm
• Have a double membrane
• Release energy for the cell through cellular respiration

Question 8

Describe the function of the Cytoskeleton

Answer 8

• A framework of protein fibres that consists of microfilaments and microtubules that give the cell it’s shape and assist the movement of materials, organelles or the whole cell.

Question 9

Describe the structure of the Nucleus

Answer 9

• Contains chromosomes whose genes control activities of a cell.
• Double membrane that has gaps and nuclear pores, through which large molecules can pass

Question 10

Describe the function of Lysosomes

Answer 10

• Small spheres that contain enzymes able to break down proteins, lipids, nucleic acids and some carbohydrates.
• Break down materials that are taken into the cell or worn-out organelles.

Question 11

Describe the function of Ribosomes

Answer 11

• Very small and spherical
• May be free in the Cytoplasm but most are attached to membranes.
• Amino acids are joined together at the ribosomes to make proteins.

Question 12

Describe the function of the Endoplasmic Reticulum

Answer 12

A network of membranes forming channels through the cytoplasm of a cell. It is used for storage, support, synthesis and transport within the cell.

Question 13

Describe the function of Centrioles

Answer 13

Occur in animal cells and are involved in the formation of the spindle during nuclear division.

Question 14

What is the function of rough ER?

Answer 14

Involved in the sythensis of proteins

Question 15

What is the function of smooth ER?

Answer 15

Involved in the manufacture of lipids.

Question 16

What is the difference between cilia and flagella

Answer 16

• Cilia are short and numerous projections, resembling tiny hairs. They occur in the cells lining the trachea.
• Flagella are longer and there are only one or two of them. In humans, the sperm cell is the only cell that has a flagellum.

Question 17

What are microtubules?

Answer 17

Hollow rods that help to maintain the shape of the cell and hold the organelles in place

Question 18

What is the role of microfilaments?

Answer 18

Move materials around the cytoplasm or move the whole cell.

Question 19

Describe the role of nuclear pores

Answer 19

Allow large molecules, such as messenger RNA, to enter and leave the nucleus in the nuclear membrane.

Question 20

State the difference between rough and smooth endoplasmic reticulum

Answer 20

Rough - when ribosomes are attached to the outside of some membranes
Smooth- when there are no ribosomes attached to the outside.