B1.1 Cell Structures

Question 1

Eukaryotic cell

Answer 1

Genetic material contained within a nucleus

Question 2

Prokaryotic cells

Answer 2

Genetic material floats within the cytoplasm

Question 3

Organelles that eukaryotic cells contain

Answer 3

Nucleus
Cell membranes
Mitochondria
Cytoplasm

Question 4

Extra sub cellular structures found in plants not animal cells

Answer 4

Chloroplast
Cell wall
Vacuole

Question 5

Function of the nucleus

Answer 5

Controls all the activities in the cell
Contains genetic material of organism arranged as chromosomes
Determines cell appearance and function

Question 6

Mitochondria

Answer 6

Provides energy by respiration

Question 7

Function of the cell membrane

Answer 7

Delicate surface membrane made from 2 layers of phospholipid
Holds the cell together
Controls what goes in and out of the cell

Question 8

Cytoplasm

Answer 8

Transfers energy, stores food
Jelly like substance where 100s of reactions take place making up metabolism

Question 9

Cell type that is relatively large 10 - 100 um

Answer 9

Eukaryotic cells
Plant and animal cells

Question 10

Who discovered cells using his self designed microscope in 1665

Answer 10

Robert Hooke

Question 11

MRS GREN

Answer 11

Movement
Respiration
Sensivity
Growth
Reproduction
Excretion
Nutrition

Question 12

Cell type that is simple and typically smaller at 1 - 10um

Answer 12

Prokaryotic cells
Bacteria cells

Question 13

What are ribosomes

Answer 13

Tiny granules on membrane and in cytoplasm of cell
Ribosomes are where proteins are made in the cell

Question 14

Chloroplast

Answer 14

Harnesses energy from the sun for photosynthesis

Question 15

Vacuole

Answer 15

Large cavity in plant cells filled with cell sap
Helps keep the cell rigid, pushing outwards

Question 16

Cell wall

Answer 16

Surrounds the cell
Made from cellulose which is a tough rubbery fibre

Question 17

Archaea

Answer 17

Primitive bacteria-like organisms

Question 18

What is a plasmid and its advantage

Answer 18

Circular piece of DNA found in bacteria cells
Gives the bacterium advantages such as antibiotic resistance

Question 19

Pili

Answer 19

Tiny hair like structures that allow the cell to attach to structures, such as the cells in the digestive tract
Used to transfer genetic material between bacteria cells

Question 20

Function of a slime capsule

Answer 20

Protects bacteria from drying out and from poisonous substances
Helps bacteria stick to smooth surfaces

Question 21

Structures and organelles to find in a bacteria cell

Answer 21

Cell wall
Cell membrane
Flagella
Single loop DNA
Plasmids
Pili
Cytoplasm
Slime capsule

Question 22

3 examples of commonly found bacteria

Answer 22

E. coli - food poisoning
Streptococcus - sore throats
Streptomyces - bacteria in soil and used to develop antibiotic streptomycin

Question 23

Flagellum

Answer 23

Tail like structures that allow bacteria cells to move through liquids

Question 24

Parts of a light microscope

🔬

Answer 24

Lens
Coarse focussing wheel (top wheel)
Revolving nosepiece
Arm
Objectives
Stage
Fine focussing wheel (bottom wheel)
Mirror
Base
🔬

Question 25

Magnification equation triangle

Answer 25

image size
—————————————————
Magnification x size of actual object

Question 26

Resolution

Answer 26

Degree to which it is possible to distinguish between 2 objects that are very close together
Higher the resolution, the greater the detail you may see

Question 27

Types of electron microscope

Answer 27

Transmission electron microscope (TEM)
Examine extremely thin slice or section of cells or tissues
Revelled subcellular structures in cells not visible with a light microscope such as mitochondria and chloroplasts

Scanning electron microscope (SEM)
Large depth of field so can be used to examine surface structure of specimens
Produce a 3D image of a surface by bouncing a beam of electrons off a specimen

Question 28

millimetres (mm) to micrometers (um)

Answer 28

1mm = 1000um

Question 29

Why staining is used

Answer 29

Makes organelles more visible under the microscope,
because cells are transparent

Question 30

Light microscopes vs electron microscopes

Answer 30

Light microscopes:
Cheap to buy and operate
Small and portable
Simple to prepare sample
Natural colour of sample is seen unless staining is used
Specimens can be dead or living
Resolution up to 0.2 um

Electron microscopes:
Expensive to buy and operate
Large and difficult to move
Sample preparation is complex
Black and white images produced
Specimens have to be dead
Resolution up to 0.1 nm

Question 31

Type of microscope most used in schools

Answer 31

Compound microscope