Cell Structure

Question 1

What does the nucleus do?

Answer 1

The nucleus contains the genetic material of the cell and controls the activities.

Question 2

What is the nuclear envelope?

Answer 2

The nuclear envelope is the double membrane that surrounds the nucleus.

Question 3

What does the nuclear envelope do?

Answer 3

It controls what goes in and out of the cell,

Question 4

What are the nuclear pores?

Answer 4

They are holes that allow the passage of large molecules in/out of the nucleus

Question 5

What is the nucleoplasm?

Answer 5

Granular, jelly like substance that makes up most of the nucleus

Question 6

What is the nucleolus?

Answer 6

A small spherical region in the nucleus.

Question 7

What is the function of the nucleolus?

Answer 7

Manufactures ribosomal RNA and assembles the ribosomes

Question 8

What is the main function of the mitochondria?

Answer 8

Produce energy in the form of ATP

Question 9

What is the structure of the mitochondria?

Answer 9

They have a double membrane structure.

Question 10

What are cristae?

Answer 10

Extensions of the inner membrane

Question 11

What do cristae provide?

Answer 11

They provide a large surface area for the attachment of enzymes and other proteins involved in respiration

Question 12

What is the matrix?

Answer 12

A jelly substance in the mitochondria that contains proteins, lipids, ribosomes and DNA

Question 13

What part of respiration takes place in the mitochondria?

Answer 13

The aerobic part (Krebs cycle and the oxidative phosphorylation pathway)

Question 14

What is the function of chloroplasts?

Answer 14

To carry out photosynthesis

Question 15

What is the chloroplast envelope?

Answer 15

double plasma membrane that surrounds the organelle

Question 16

What does the chloroplast envelope do?

Answer 16

Controls what comes in and out of the organelle as it is highly selective

Question 17

What are grana?

Answer 17

Stacks of up to 100 thylakoids

Question 18

What are thylakoids

Answer 18

Disks that contain chlorophyll.

Question 19

What takes place in the thylakoids?

Answer 19

The first stage of photosynthesis (light absorption)

Question 20

What is the stroma?

Answer 20

Fluid filled matrix

Question 21

What takes place in the stroma?

Answer 21

The second stage of photosynthesis (synthesis of sugars)

Question 22

What do the granal membranes provide?

Answer 22

Large surface area for the attachment of chlorophyll, electron carriers and enzymes that carry out the first stage of photosynthesis.

Question 23

What is in the stroma?

Answer 23

All the enzymes for the second stage of photosynthesis

Question 24

Do chloroplasts have any other organelles?

Answer 24

They have ribosomes and their own DNA

Question 25

What is the ER?

Answer 25

System composed of sheet like membranes.

Question 26

What is the rough ER?

Answer 26

ER with attached ribosomes

Question 27

What is the function of the rough ER?

Answer 27

Provide large surface area for the synthesis of proteins. Provide a pathway for the transport of materials throughout the cell

Question 28

What is the function of the smooth ER?

Answer 28

To synthesise store and transport lipids. To synthesise store and transport carbohydrates.

Question 29

What is the golgi body?

Answer 29

Stacks of membranes that make up flattened disks with small hollow rounded structures called vesicles.

Question 30

What is the function of the golgi body?

Answer 30

To modify proteins, often adding non protein elements such as carbohydrates. Produce secretory enzymes. Secrete carbohydrates. Transport store and modify lipids. Form lysosomes.

Question 31

What are lysosomes?

Answer 31

Vesicles containing enzymes such as proteases and lipases.

Question 32

What is the function of the lysosomes?

Answer 32

Hydrolyse material ingested by phagocytic cells. Release enzymes outside of the cell. Digest worn out organelles. Completely break down cells after death (autolysis

Question 33

Where are lysosomes especially abundant?

Answer 33

In secretory cells such as epithelial cells and in phagocytic cells.

Question 34

What are ribosomes?

Answer 34

Small cytoplasmic granules

Question 35

What is the function of ribosomes?

Answer 35

To synthesise proteins

Question 36

What size of ribosomes are found in eukaryotic cells?

Answer 36

80S

Question 37

What size of ribosomes are found in prokaryotic cells?

Answer 37

70S

Question 38

What are ribosomes made of?

Answer 38

Two subunits

Question 39

What are the subunits called?

Answer 39

Large and Small

Question 40

What do the subunits contain?

Answer 40

Ribosomal RNA and proteins

Question 41

What is a cell wall made from?

Answer 41

Microfibrils of the polysaccharide cellulose

Question 42

What does the cell wall provide?

Answer 42

It holds the cells turgid, prevents them from bursting. Also allows water to pass along it.

Question 43

What are the cell walls of fungi made from?

Answer 43

Chitin (another polysaccharide)

Question 44

What is the middle lamella?

Answer 44

Thin layer that marks the boundary between adjacent cell walls and cements adjacent cells together.

Question 45

What does the vacuole contain?

Answer 45

Mineral salts, sugars, amino acids, wastes and sometimes pigments.

Question 46

Waht do vacuoles do to the cell?

Answer 46

Keep the cell turgid. The sugars and amino acids can act as a temporary store of food.

Question 47

What do the pigments in the vacuole do for the plant?

Answer 47

Attract pollinating insects