Chapter 1

Question 1

Plasma Membrane

Structure & Function

Answer 1

Semi permeable barrier that defines the outer perimeter of the cell

Made of lipids and proteins

Made of ampiapathic phospholipid by-layer

Question 2

Simple Diffusion

Answer 2

Process of spontaneous spreading of a substance going from an area of high concentration to an area of low concentration

A concentration gradient exists

Gradient can be chemical or electrical
Unequal charge or unequal distribution of molecules.

Question 3

Osmosis

• Hypotonic
• Hypertonic
• Isotonic

Answer 3

Diffusion of water across a semi permeable membrane. Moving from high water concentration to low.

Hypotonic - Low solute concentration.
Hypertonic - High Solute concentration.
Isotonic - osmotic pressure is equal.

Question 4

Carrier Mediated Transport

Answer 4

Amino Acids, Sugars + other solutes need to bind to proteins (carriers) to get across the membrane.

Carriers are limited so there is a levelling off point
- Saturation Kinetics

Question 5

2 X Types of mediated transport

Answer 5

Facilitated - a carrier helps it across. Down Ion channels

Active - when energy is used (ATP) to transport across a gradient

Question 6

Endocytosis Vs Exocytosis

Answer 6

Endo -
Substance brought into a cell
Cell membrane invaginate m, pinches off + is released into the cell.
Solids, phagocytosis - Fluids Pinocytosis

Exo
Stuff evacuated from cells. Versicle fuses with membrane - releases it outside.

Some ‘kiss and run’
Some join the wall

Question 7

Cytoplasm

Answer 7

Interior of the cell - Everything inside the membrane

Question 8

Cytosol

Answer 8

The solution that bathes the organelle - contains solution like amino acids, proteins etc.

Question 9

Cytoskeleton

Answer 9

Extends through the cell

Gives shape and important for intracellular transport

Question 10

Mitochondrion

Answer 10

Power house of the cell - ATO

Inner membrane sac folds called Cristae

Matrix fluid inside the inner membrane contain enzymes for krebb cycle.

KC to Make ATP

Have their own DNA to replicate independently

Question 11

Lysomes

Answer 11

Suicide Sacs

Can release acids to destroy a dead cell

Can form with a versicle to just destroy a pathogen.

Question 12

Endoplasmic Reticulum

Answer 12

Synthesis Centre

Goes from call membrane to the nucleus membrane

Rough ER has proteins + ribosomes on - syntheses proteins

Smooth ER - synthesises lipids

Question 13

Golgi Apparatus

Answer 13

Export Department

Wraps proteins in versicle for exocytosis

Question 14

Peroxisome

Answer 14

Membrane bound vesicles that contain enzymes to determine oxidative of aminos

Question 15

The nucleus

Answer 15

Surrounded by the nuclear envelope
- Nuclear pores along that
— They control the in and out of the nucleus

Responsible for protein synthesis

DNA found here in chromatin + chromosomes

Question 16

Chromosomes

Answer 16

Extremely folded chromatin

Maintained by histone proteins - made of nucleosome - chromatin

Question 17

Cell Cycle

Time - Stages

Answer 17

18-22 Hours

Mitosis - nuclear division - usually followed by cell division.

Mitosis and cytokinesis together make (m) myotic period.

Resting cells go into G0

Interphase G, S, Gn, - 90% of the cycle

G, prepare for DNA synthesis - replicate DNA (S)

Replicate of chromosomes (G2)