Cells

Question 1

what are the 4 functions of the cell membrane?

Answer 1

1. physical barrier between cytoplasm and fluid outside of the cell
2. Semi-permeable, controls what enters and exits the cell (phospholipid bilayer)
3. sensitivity, its the first part of the cell to be affected by change in extracellular fluid
4. support, cytoskeleton is attached to the cell membrane

Question 2

What is the function of the cytoplasm?

Answer 2

Jelly like substance that fills the space between the cell membrane & nucleus

Question 3

What is the cytosol?

Answer 3

The liquid part of the cytoplasm, it’s 75-95% water

Question 4

What is the function of the nucleus

Answer 4

Contains DNA - chromosomes/chromatin who’s genes control the activities of the cell

Question 5

What is the function of the ribosome

Answer 5

Synthesis proteins by assembling amino acids, proteins travel through endoplasmic reticulum to the Golgi body

Question 6

function of the endoplasmic reticulum

Answer 6

stores and transports molecules using channels

surface of the membrane is a site for chemical reactions to occur

Question 7

function of the Golgi body

Answer 7

Responsible for the modification of proteins and packaging them for secretion from the cell

Question 8

function of the lysosomes

Answer 8

Contains powerful digestive enzymes

Question 9

function of the mitochondria

Answer 9

Powerhouse of the cell

site for cellular respiration

Question 10

function of the nucleolus

Answer 10

manufactures and stores RNA

Question 11

What is the fluid mosaic model

Answer 11

The cell membrane is a phospholipid bilayer, the parts consist of a hydrophilic (water loving) head on the outside and a hydrophobic (water hating) tail in the inside.

Question 12

function of vesicles

Answer 12

sack containing waste waiting to be removed from the cell

Question 13

why are cells so small?

Answer 13

The longer it takes a cell to pass across the cell membrane, the less efficient it is

A large cell could not support itself because it would not have enough surface area to absorb and remove the products required for efficient functioning

Question 14

what is diffusion?

Answer 14

the spreading of particles (liquid or gas) until they are evenly distributed over the available space

Question 15

what is osmosis?

Answer 15

diffusion of water through a different permeable membrane

high solvent concentration -> low concentration

glucose and ions such as sodium cannot enter through diffusion

water can fit through lipid tails or through channel proteins