Week 1 Content (Cells)

Question 1

What are the three main componenets of the cell

Answer 1

1. Plasma membrane:
   * Outer cell membrane
2. Cytoplasm:
   * Cytosol: the intracellular fluid
   * Cytoskeleton
   * Organelles
3. Nucleus:
   * Holds most of the genetic material

Question 2

What term is used to describe the Plasma membrane

Answer 2

Fluid mosaic model

Question 3

Outline the diagram

Answer 3

Question 4

Parts of the Phospholipid bilayer

Answer 4

Phospholipid bilayer

Polar parts (heads) are hydrophilic (love water)
- face on both surfaces towards an aqueous environment
- two aqueous compartments - inside cell and outside cell
Non-polar parts (tails) are hydrophobic (hate water)
- line up next to each other in the interior of the bilayer.

Question 5

Types of proteins in the cell membrane

Answer 5

INTEGRAL AND PERIPHERAL PROTEINS

Question 6

The funcition of a GLYCOLIPID

Answer 6

Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition (connecting cells to form tissue)

Question 7

The types of Passive transport

Answer 7

Simple diffusion and Facilitated diffusion

Question 8

Define simple diffusion

Answer 8

Simple diffusion:
* Substances move from high
concentration to low concentration
through the plasma membrane.(sovents) (liquid)

Question 9

Define Facilitated diffusion:

Answer 9

Substances move from high
concentration to low concentration
via a protein (solutes (ions))

Question 10

What are the two different facilitaed protein channels

Answer 10

Channel-mediated facilitated diffusion and carrier-mediated facilitated diffusion (Transporter Protein)

Question 11

Define Active transport

Answer 11

Substances move from low concentration to high concentration via a protein and energy against the concentration gradient (hydrolysis of atp)

Question 12

Vesicular transport….

Answer 12

Transport bulky material in small vesicles

Question 13

Types of movement for visicular transport

Answer 13

exo cytosis and endo cytosis

Question 14

What makes the cytoskeleton

Answer 14

Micro filaments, intermidiate filaments and microtubles

Question 15

1) Microfilaments:

Answer 15

Aid in maintaining cell shape
and cell motility

Question 16

Intermediate filaments:

Answer 16

High tensile strength
* Internal guy-wires to resist
pulling forces exerted on the
cell.

Question 17

Microtubules:

Answer 17

Functions:
* Repositioning of organelles
* Chromosomal movement during
division of cells
* Movement of cilia and flagella

Question 18

1) Microfilaments:Intermediate filaments:Microtubules: are part of the …………..

Answer 18

cyto skeleton

Question 19

Outline the diagram

Answer 19

Question 20

Nuclear Envelope

Answer 20

The nuclear envelope
* Consists of a double
Membrane

• Outer surface is
  continuous with RER
• Punctuated by nuclear
  pores
  – Aqueous transport
  channel regulating entry
  and exit of molecules.
• Selectively permeable
  – Pores are hydrophobic

Question 21

Chromatin

Answer 21

The DNA from one
cell, stretched out, is
approx 2 meters long.
– Needs to be
condensed!
* Chromatin is composed
of approx.
– 30% DNA
– 60% Histone proteins
– 10%RNA

Question 22

The Nucleolus

Answer 22

Sits inside the nucleus.
* Not membrane bound.
* Typically one or two per
nucleus.
* Spherical bodies that
make ribosomal subunits.
* Subunits then leave the
nucleus via the nuclear
pores.
* Senses cellular stress.

Question 23

The nucleus consists of three regions / Function

Answer 23

• Nuclear envelope
• Nucleoli
• Chromatin

Main store for the
cell’s
genetic information

Question 24

The Endoplasmic Reticulum

Answer 24

A network of membranes closely associated with the nucleus.

Question 25

What are the two classes of endo plasmic reticulum

Answer 25

Rough ER (RER) * ribosomes attached to surface * “studded” appearance Smooth ER (SER) * no ribosomes attached

Question 26

The steps of the nucleus and er

Answer 26

DNA transcribes on RNA and then translates into proteins though ribosomes on the endoplasmic reticulum (ribosomes makes proteins from RNA)

Question 27

What are the three pathways of the Golgi apparatus

Answer 27

Question 28

Where do the vecicles from the rer travel to

Answer 28

the membrane of the the golgi apparatus

Question 29

What happens to the proteins in the golgi apparatus

Answer 29

The proteins are modified and then packaged in different vesicle type

Question 30

What are the functions of the Mitochondria

Answer 30

The synthesis of ATP (adenosine triphosphate)

Question 31

The functions of lysosomes

Answer 31

Perform metabolic activities 1) breakdown of glycogen to glucose 2) breakdown of bone 3) ca2+ ions into bloodstream

Question 32

Traits of the mitochondria

Answer 32

Contain their own DNA and RNA/ribosomes