Chapters 3 and 4- Cells exchange material, cell membrane

Question 1

What is the function of the cell membrane?

Answer 1

separates cell from neighbouring cells and the external environment. Determines which substances get into or out of the cell

Question 2

What is the function of the cytoplasm?

Answer 2

all structures are suspended in it

Question 3

What is the function of the nucleus?

Answer 3

contains genetic material and produced ribosomal RNA

Question 4

What is the function of ribosomes?

Answer 4

produces proteins

Question 5

What is the function of the endoplasmic reticulum?

Answer 5

provides a surface on which chemical reactions can occur. Also used for storage or transport of materials

Question 6

What is the function of the Golgi apparatus?

Answer 6

modifies proteins and packages them into vesicles for secretion from the cell

Question 7

What is the function of lysosomes?

Answer 7

breaks down materials that are taken into the cell or breaks down worn out cells

Question 8

What is the function of the mitochondria?

Answer 8

releases energy for the cell through the process of respiration

Question 9

What is the function of the centrioles?

Answer 9

involved in the production of the cell (mitosis)

Question 10

What is the function of the cilia/flagella?

Answer 10

moves the cell of substances over the surface of the cell

Question 11

What is the function of the cytoskeleton?

Answer 11

provides support

Question 12

What is the function of a vacuole?

Answer 12

stores food or any nutrients the cell might need to survive

Question 13

What is the chemical equation for the production of cells?

Answer 13

food + oxygen—–energy + carbon dioxide + water dioxide

Question 14

What is homeostasis?

Answer 14

The maintenance of a constant internal environment of cells despite fluctuations in the external environment

Question 15

What are the 4 functions of a cell membrane?

Answer 15

1. physical barrier: protects cell
2. regulates passage of materials: controls what enters and leaves the cell, done through semipermeable membrane
3. sensitivity: protein receptors are sensitive to certain molecules ie hormones
4. support: microfilaments attached which are part of the cytoskeleton

Question 16

What is the main building block of a cell membrane?

Answer 16

phospholipids

Question 17

What do phospholipids consist of?

Answer 17

• phosphate head
• glycerol backbone
• 2 fatty acid tails

Question 18

Describe the phospholipid heads and tails

Answer 18

head group is hydrophilic (water loving) and tails are hydrophobic (water hating)

Question 19

What are the 4 types of proteins within the bilayer?

Answer 19

1. channel: form a central pore to allow small molecules to pass through by simple diffusion
2. receptor: receive information to produce a response
3. carrier: only allow specific molecules to bind to it, facilitated diffusion
4. cell identity markers: prevents attack by the body’s immune system

Question 20

What are the 3 processes involved in the transport of substances in and out of the cell

Answer 20

1. diffusion
2. carrier-mediated transport
3. vesicular transport

Question 21

What are passive and active processes?

Answer 21

passive processes require no cellular energy or ATP

active processes require ATP and include specific membrane pumps and phagocytosis/pinocytosis

Question 22

What factors effect the rate of diffusion?

Answer 22

1. surface area
2. barriers
3. temperature

Question 23

What is osmosis?

Answer 23

the diffusion of water across a semi-permeable membrane

Question 24

What is solute and solvent?

Answer 24

solute is sugar, solvent is water

Question 25

What is endocytosis?

Answer 25

process that brings materials into the cell

Question 26

What is pinocytosis and phagocytosis?

Answer 26

specific types of endocytosis

Question 27

What is exocytosis?

Answer 27

the release of molecules from the cell. ATP is required