unit 2 cells & immunity

Question 1

What is a nuclear envelope?

Answer 1

A double membrane, surrounding the nucleus, which controls the entry and exit of materials

Question 2

What is the function of the mitochondria?

Answer 2

The site of aerobic respiration and for the production of ATP.

Question 3

What are cristae?

Answer 3

Fold in the inner membrane of the mitochondria, they are the site of oxidative phosphorylation.

Question 4

What is the rough endoplasmic reticulum

Answer 4

System of membranes that is continuous with the nucleus, with ribosomes on the outer surface. Site of synthesis and transportation of proteins and glycoproteins.

Question 5

How does the structure of the rough endoplasmic reticulum help enable synthesis of proteins?

Answer 5

The rough endoplasmic reticulum has ribosomes and a large surface area.

Question 6

What is the smooth endoplasmic reticulum?

Answer 6

Site of synthesis, storage and transportation of lipids and carbohydrates.

Question 7

What are the four functions of the golgi apparatus?

Answer 7

1. produces secretory enzymes and carbohydrates
2. stores and modifies proteins and triglycerides
3. forms vesicles for transporting proteins/triglycerides
4. forms lysosomes

Question 8

What is a lysosome?

Answer 8

A lysosome is membrane- bound organelle that releases hydrolytic enzymes.

Question 9

What is the structure of ATP?

Answer 9

A pentose sugar (ribose), a nitogenous base (adenine) and three inorganic phosphate groups.

Question 10

What is the function of ATP?

Answer 10

An immediate source of energy for biochemical processes and synthesis of biological molecules.

Question 11

How does the structure of ATP make it a good source of immediate energy?

Answer 11

The bonds between the phosphate groups have a low activation energy . This means they can be easily broken . Breaking the bonds releases energy.

Question 12

What is active transport?

Question 13

What are grana?

Answer 13

Stacks of thylakoids found in the chloroplast.

Question 14

What are thylakoids?

Answer 14

Flattened sacs in the chloroplast, containing chlorophyll. Site of light dependent reaction for photosynthesis.

Question 15

What is the stroma?

Answer 15

The stroma is the matrix of the chloroplast in a plant cell. Sight of the light independent reaction for photosynthesis.

Question 16

What is the function of the plant cell wall?

Answer 16

Provides rigidity to the cell and stops the cell from bursting by exerting inward pressure to prevent osmosis. This enables turgidity which makes the plant semi rigid

Question 17

What are plant walls mainly composed off?

Answer 17

The polymer, cellulose

Question 18

What is a vacuole?

Answer 18

A fluid filled sac with a single membrane.

Question 19

What is the function of the vacuole in a plant cell?

Answer 19

It supports the plant by making it turgid. Stores sugars and amino acids, which can act as a temporary food storage. In petal cells, it can store pigments to attract pollinating insects.

Question 20

State three purposes of mitosis

Answer 20

Mitosis is needed for growth, repair and asexual reproduction

Question 21

State two purposes of meiosis

Answer 21

Meiosis is needed for the production of haploid cells for asexual reproduction. It helps ensure genetic variability.

Question 22

Define mitosis in the terms of the daughter cells produced

Answer 22

The cell divides once to produce two daughter cells. Each daughter cell has an identical copy of DNA produced by the parent in reproduction.

Question 23

Define meiosis in the terms of the daughter cells produced

Answer 23

The cell divides twice to produce four daughter cells. Each daughter cell is genetically different.

Question 24

What is the function of the phospholipid bilayer?

Answer 24

Allows diffusion of lipid soluble substances. Prevents movement of water soluble substances.

Question 25

What are two functions of cholesterol embedded in the cell membrane?

Answer 25

Reduce fluidity and permeability of the cell membrane. Increase rigidity of the cell membrane.

Question 26

What is a glycoprotein?

Answer 26

A protein attached to a carbohydrate chain on the cell surface membrane.

Question 27

What are the two functions of a glycoprotein?

Answer 27

Acts as a recognition site for hormones, neurotransmitters and other cells. Helps cells attach together to form tissues.

Question 28

Define simple diffusion

Answer 28

A passive method of transport across the cell membrane via the phospholipid bilayer.

Question 29

Define facilitated diffusion.

Answer 29

A passive method of transport across membranes involving carrier proteins and channel proteins.

Question 30

What type of transport are channel proteins involved in?

Answer 30

Involved in facilitated diffusion across the cell membrane.

Question 31

What type(s) of transport are carrier proteins involved in?

Answer 31

Involved in facilitated diffusion and active transport across the cell membrane

Question 32

What is the term used to define the response of T cells to a foreign antigen?

Answer 32

Cell mediated response

Question 33

Define humarol immunity

Answer 33

The response of B-lymphocytes to a foreign antigen, clonal selection and release of monoclonal antibodies.

Question 34

How does the secondary immune response differ from the primary immune response?

Answer 34

In the secondary immune response, plasma cells and antibodies are produced at higher speed and concentration as a result of memory cells produced during the primary immune response

Question 35

What is an antibody?

Answer 35

A protein produced by B lymphocytes in response to the presence of a specific antigen.

Question 36

What are monoclonal antibodies?

Answer 36

Antibodies with the same tertiary structure, produced from cloned B-lymphocytes