Cell Biology

Question 1

Eukaryotic cells are…

Answer 1

…large, complex organisms
(Plant and animal cells)

Question 2

What organelles do plant cells have

Answer 2

Cells wall
Nucleus
Cell membrane
Vacuole
Chloroplast
Mitochondria
Cytoplasm
Ribosomes

Question 3

What organelles do animal cells have

Answer 3

Nucleus
Cell membrane
Mitochondria
Cytoplasm
Ribosomes

Question 4

Prokaryotic cells are…

Answer 4

…non-complex organisms
(Bacteria)

Question 5

What organelles are in bacteria cells

Answer 5

Ribosomes
Loose chromosomal DNA
Cell wall
Cytoplasm
Plasmid DNA
Cell membrane
Flagellum

Question 6

Functions of the nucleus

Answer 6

Controls the cell and stores DNA

Question 7

Functions of the cytoplasm

Answer 7

Carry out chemical reactions and hold organelles in place

Question 8

Functions of the ribosomes

Answer 8

Carry out protein synthesis

Question 9

Functions of the chloroplasts

Answer 9

Carry out photosynthesis

Question 10

Functions of the cell membrane

Answer 10

Controls what enters and exits the cell

Question 11

Functions of the cell wall

Answer 11

Supports and protects the cell

Question 12

Functions of the vacuole

Answer 12

Stores sugars/water and salt. Turgid shape

Question 13

Functions of the mitochondria

Answer 13

Carry out respiration which releases energy

Question 14

What is DNA

Answer 14

The molecule in the cell that stores genetic information

Question 15

What is a gene

Answer 15

A short section of DNA found in a chromosome that controls the development of 1 characteristic

Question 16

What is a chromosome

Answer 16

A long strand of DNA that contains many genes

Question 17

How many pairs of chromosomes are there in 1 cell

Answer 17

23
Except red blood cells and sperm/egg cells where the pairs are separated

Question 18

What chromosomes do men have

Answer 18

X and Y

Question 19

What chromosomes do women have

Answer 19

X

Question 20

Equation for mitosis stage length

Answer 20

Length of stage = number of cells in stage (divided by) total number of cells
X length of cell cycle

Question 21

Stage 1 mitosis

Answer 21

1. The cell grows, producing more mitochondria and ribosomes
2. The DNA replicates (interphase)

Question 22

Stage 2 mitosis

Answer 22

3. The chromosomes line up in the centre of the cell
4. They get pulled to opposite sides of the cell

Question 23

Stage 3 mitosis

Answer 23

5. The cell membrane and cytoplasm divide (cytokinesis)
6. Two genetically identical daughter cells are produced

Question 24

What substances are diffused through cells

Answer 24

Carbon dioxide
Glucose
Oxygen
Amino acids

Question 25

Definition of diffusion

Answer 25

The movement of particles from an area of higher concentration to an area of lower concentration

Question 26

What factors is diffusion affected by

Answer 26

Surface area Concentration gradient Temperature (Not energy - passive process)

Question 27

Large surface area…

Answer 27

…increases space available for exchange

Question 28

Large blood supply…

Answer 28

…maintains steep concentration gradient

Question 29

Thin walls…

Answer 29

…short diffusion pathway/distance

Question 30

Equilibrium meaning

Answer 30

No net movement, equal concentration

Question 31

Isotonic meaning

Answer 31

Same concentration of solute as inside the cell

Question 32

Hypertonic meaning

Answer 32

Higher concentration of solutes inside the cell (Shrinks/shrivels) (Plants plasmolysis)

Question 33

Hypotonic meaning

Answer 33

Lower concentration of solute inside the cell (Expands/bursts) (Plants become rigid)

Question 34

Osmosis definition

Answer 34

The diffusion of water particles from an area of high water concentration to an area of low water concentration across a partially permeable membrane

Question 35

Is energy required for osmosis

Answer 35

No it’s a passive process

Question 36

Definition of active transport

Answer 36

When molecules move from an area of low concentration to an area of high concentration against the concentration gradient

Question 37

What does active transport require

Answer 37

Energy Protein carrier molecule

Question 38

What factors affect active transport

Answer 38

Temperature Surface area Oxygen availability (respiration)

Question 39

What do root hair cells absorb through active transport

Answer 39

Mineral ions

Question 40

What do villi absorb through active transport

Answer 40

Glucose

Question 41

What do you use to place a cell on a microscope slide

Answer 41

Forceps

Question 42

What do you stain microscope slides with

Answer 42

Iodine

Question 43

Which objective lens do you start with on a microscope

Answer 43

Lowest magnification

Question 44

What does the course focus wheel do on a microscope

Answer 44

Raises the stage

Question 45

What does the glass slide do on a microscope

Answer 45

Prevents the specimen from dying out

Question 46

What is the equation for magnification

Answer 46

I =AM I - image size (mm) A - actual size (um) M - magnification

Question 47

How do you convert from mm to um

Answer 47

Multiply by 1000

Question 48

What does the head of a sperm call contain

Answer 48

Genetic material

Question 49

What does the acromosome in a sperm call contain

Answer 49

Enzymes to penetrate an egg

Question 50

What is the middle piece of a sperm full of

Answer 50

Mitochondria for energy

Question 51

Why does a nerve cell have branches (dendrites)

Answer 51

To communicate with other nerve cells, muscles and glands

Question 52

Why is the nerve cel covered in a fatty sheath

Answer 52

Insulates Speeds up nerve impulse

Question 53

Why does a root hair cell have a large surface area

Answer 53

For fast osmosis with more contact to the soil water

Question 54

What to muscle cells contain that allow contraction

Answer 54

Filaments of protein that can Slide over each other

Question 55

Why do phloem cells have companion cells

Answer 55

Because they have no mitochondria so use the mitochondria in the companion cells for energy

Question 56

What are xylem cell walls thicken with

Answer 56

Lignin

Question 57

What are stem cells

Answer 57

Cells that have not yet become specialised cells

Question 58

What can bone marrow stem cells differentiate into

Answer 58

Blood and immune system cells

Question 59

Where does cell division in plants occur

Answer 59

The meristems

Question 60

Functions and adaptations of plant structure

Answer 60

Leaf - thin (short diffusion pathway) large surface are for photosynthesis Waxy cuticle - prevents evaporation of water from leaf and entry of pathogens Upper epidermis - transparent to allow light through Palisade mesophyll - site of most photosynthesis, cells contain lots of chloroplasts and have a large surface area Spongey mesophyll - contains lots of air spaces for gas exchange Stomata - allow gases in and out of the leaf Guard cells - control opening and closing of stomata