Bio unit 1

Question 1

What are the two types of cells?

Answer 1

Eurkaryotic and prokaryotic

Question 2

What are examples of eukaryotic cells?

Answer 2

plants and animal

Question 3

What are examples of prokaryotic cells?

Answer 3

bacteria

Question 4

What do eukaryotic cells have?

Answer 4

Cytoplasm
Cell membrane
Genetic material inside the nucleus

Question 5

What do prokaryotic cells have?

Answer 5

Cytoplasm
Cell membrane
Cell wall
Genetic material (not in nucleus) has a single DNA loop and possibly one or more plasmids which are small rings of DNA.

Question 6

Nucleus

Answer 6

Controls all the activities in the cell
Contains the genes on chromosomes which carry instructions to make the proteins that are needed in order to build new cells or organisms

Question 7

Cytoplasm

Answer 7

The liquid gel in which organelles are suspended
Where most chemical reactions needed for life take place

Question 8

Cell membrane

Answer 8

Controls the entrance of substances like mineral ions and glucose into the cell.
Controls exit of substances like urea or hormones out of the cell.

Question 9

Mitochondria

Answer 9

Where aerobic respiration takes place
Releases energy for the cell
Small

Question 10

Ribosomes

Answer 10

Where protein synthesis takes place (process where cells make protein)
Makes all proteins needed in cell

Question 11

Cell wall

Answer 11

Made of cellulose
Strengthens cell and provides support

Question 12

Chloroplasts

Answer 12

Found in green parts of plant
Contain (green) chlorophyll that absorbs light for photosynthesis

Question 13

Permanent vacuole

Answer 13

Space filled with cell sap
Supports plants by keeping cells rigid.

Question 14

Animal cells contain:

Answer 14

Nucleus
Cytoplasm
Cell membrane
Mitochondria
Ribosomes

Question 15

Plant cells contain

Answer 15

Nucleus
Cytoplasm
Cell membrane
Mitochondria
Ribosomes
Chloroplasts
Permanent vacuole
Plant and algal cells also have a cell wall.

Question 16

Sperm cell job

Answer 16

It’s job is to join with an egg cell (fertilization)

Question 16

specialization

Answer 16

Most animal and plant cells are specialized
They have adaptations that help them to carry out a specific function
Differentiation is when cells become specialized

Question 17

Sperm cell structure:

Answer 17

-Flagellum, a long tail which allows it to swim
Streamlined to make swimming easier
-Mitochondria which provides the energy to allow it top swim
-Enzymes that allow them to digest the outer layer of the egg cell

Question 18

Nerve cell job

Answer 18

It’s job is to send electrical impulses around the body

Question 19

nerve cell structure

Answer 19

-Myelin protects the axon and speeds up transmission of nerve impulses
-Synapses (junctions in which an impulse to passes from one nerve cell to another)
-Dendrites increase the surface area to connect nerve cells easily

Question 20

Muscle cell job

Answer 20

Its job is to make muscle contractions

Question 21

structure of muscle cell

Answer 21

-Protein fibers can change the length of muscles (when a muscle contracts they shorten)
-Mitochondria provide energy for muscle contraction

Question 22

Animals cells specialisation

Answer 22

sperm, muscle, nerve

Question 23

Root hair cells job

Answer 23

Its job is to allow plants to absorb more water

Question 24

Structure root hair cell

Answer 24

Structure:
-Hairs increases surface area of root to absorb water
-No chloroplast because underground
-Permanent vacuole that speeds up movement of water by osmosis from soil to across root hair cells.
-Mitochondria, energy for active transport of mineral ions to the cells.

Question 25

Xylem cell job

Answer 25

Found in plants stem, their job is to form long tubes that carry dissolved minerals from the roots to the leaves(only upwards)

Question 26

Xylem cell structure

Answer 26

-Thick walls that contain chemical called lignin, spirals and rings of lignin provide support for cell
-Lignin causes cell to die and form hollow tubes, allow mineral ions and water to move through them

Question 27

Phloem cell job

Answer 27

Its job is to carry food made by photosynthesis around the plant(up and down)

Question 28

phloem cell structure

Answer 28

-Sieve plates allow the water that carries dissolved food to move up and down tubes to where needed.
-Companion cells for support
-Mitochondria of companion cells provide energy to move dissolved food around.

Question 29

Plant cell specialization

Answer 29

root hair cell, xylem, phloem

Question 30

Cell differentiation

Answer 30

As an organism develops, cells go through a process called differentiation.
Most animal cells differentiate at an early stage
Most plant cells have the ability to differentiate throughout life
In animals that are mature, cell division (making new cells) is mainly there to repair and replace
When a cell differentiates it gets a new subcellular structure so it is able to carry out a certain function, it has become a specialized cell.

Question 31

How has electron microscopy increased understanding of sub-celluar structure?

Answer 31

help us to see smaller things in more detail. e.g plasmids

Question 32

Difference of prokaryote and eukaryote?

Answer 32

• Prokaryotes are smaller
• Prolaryotes do not have nuclues
  -Prokaryotes have circular DNA, Eukaryotes have linear DNA.

Question 33

Two types of microscopes

Answer 33

light and electron

Question 34

Difference between electron and light?

Answer 34

-Electron has a higher magnification and resolving power than light.
- Electron can study cells in finer detail
- Electron enable biologist to understand sub-celluar structures.

Question 35

magnification formula

Answer 35

size of image/size of real object

Question 36

How do bacteria multiply?

Answer 36

By simple cell division(binary fission) every 20 mins if have enough nutrients and suitable temperature.

Question 37

How can bacteria be grown?

Answer 37

in nutrient broth solution or as colonies on an agar jelly plate

Question 38

What is required for investigating the action of disinfectants and antibiotics?

Answer 38

Uncontaminated cultures of microorganism