TOPIC 1 CELL BIOLOGY

Question 1

Cell theory

Answer 1

All living things are composed of cells
The cell is the smallest unit of life
Cells only arise from pre existing cells

Question 2

Cells that don’t conform to cell theory

Answer 2

Striated muscle- They have multiple nuclei
Giant Algae- Grows to very large sizes challenging larger organisms being made of microscopic ones

Question 3

Calculation of Magnification

Answer 3

Magnification= Image size / actual size

Question 4

Calculation of Actual size

Answer 4

Actual size= Image size / magnification

Question 5

Definition of Cell Differentiation

Answer 5

Process during development where newly formed cells become more specialized as they mature

Question 6

Draw Prokaryotic cell and label

Question 7

Draw a Eukaryotic cell and label

Question 8

Draw a plant cell

Question 9

Prokaryotic cell

Answer 9

Lack a nucleus
Divide by Binary Fission
DNA a single circular loop

Question 10

Process of Binary Fission

Answer 10

Circular DNA is copied in response to signal
Two DNA attach to the membrane
Membrane elongates and pinches off forming two cells.

Question 11

Eukaryotes

Answer 11

Contain a Nucleus

Question 12

Advantages of electron microscopes

Answer 12

Higher range of magnification
Higher resolution

Question 13

Disadvantage of electron microscope

Answer 13

Cant display living species in natural color

Question 14

Definition of an organelle

Answer 14

Specialized sub structure within a cell

Question 15

Example of organelles

Answer 15

Everything- Ribosomes and Plasma membrane
Plants only- Chloroplast and Cell Wall
Animal only- Lyosome

Others include mitochondria and Nucleus

Question 16

Difference between Eukaryotic and Prokaryotic

Answer 16

NO Nucleus vs nucleus
Binary fission vs Meiosis
70s ribosomes vs 80s ribosomes

Question 17

Structure of a Phospholipid

Answer 17

Hydrophilic head composed of glycerol and phosphate
2 Hydrophobic tail composed of fatty acid

Question 18

Properties of the Phospholipid bilayer

Answer 18

Held together by weak hydrophobic interactions between tails

Restrict passage of substances

Question 19

Draw the Fluid-Mosaic model

Question 20

Integral Protein

Answer 20

Permanently attached to the membrane

Question 21

Peripheral protein

Answer 21

Temporarily attached to the membrane

Question 22

Purpose of Cholesterol

Answer 22

Functions to maintain integrity and mechanical stability

Interacts with phospholipid tails to recuce fluidity in the cell

Question 23

Diffusion

Answer 23

The net movement of molecules from a high to a low concentration

Question 24

Osmosis

Answer 24

The net movement of water across a semi-permeable membrane from low solute concentration to high solute concentration

Question 25

Meaning of hypertonic

Answer 25

High solute concentration which gains water

Question 26

Hypotonic

Answer 26

Low solute concentration which loses water

Question 27

Isotonic

Answer 27

Same solute concentration which has no movement of water

Question 28

Active Transport

Answer 28

Requires energy and moves against the concentration gradient