unit 1.2 - cell structure and organisation

Question 1

what is a eukaryotic cell?

Answer 1

refers to cells that have a nucleus and membrane bound organelles

Question 2

example of a eukaryotic cell?

Answer 2

plant and animal cells

Question 3

Nucleus?

Answer 3

contains DNA which codes for or controls protein synthesis

Question 4

Nucleus Pores

Answer 4

Allow the transport of mRNA and ribosomes out of the nucleus.

Question 5

Nucelolus

Answer 5

synthesis rNA tRNA and ribosomes

Question 6

Nuclear envelope

Answer 6

Separates the contents of the nucleus form the cytoplasm.

Question 7

Chromatin

Answer 7

condenses before cell division to form chromsomes

Question 8

Rough
Endoplasmic
Reticulum

Answer 8

Packaging and storing proteins. Producing transport vesicles
which merge to form the Golgi body.

Question 9

Endoplasmic reticulum

Answer 9

ribosomes attached to it

Question 10

Golgi body

Answer 10

Packaging proteins for secretion from the cell. Modification
of proteins

Question 11

lysosomes

Answer 11

contains powerful digestive enzymes to break down worn out organelles or cells

Question 12

centrioles

Answer 12

form the spindle during cell division. not present in higher plant cells

Question 13

mitochondria

Answer 13

ATP synthesis by aerobic respiration

Question 14

chloroplasts

Answer 14

Contain photosynthetic pigments which trap light energy for
photosynthesis.

Question 15

Vacuole

Answer 15

Contains cell sap and stores solutes such as glucose. Swells
due to osmosis for turgidity.

Question 16

Ribosomes

Answer 16

Protein synthesis. Primary protein structure is formed at the
ribosome.

Question 17

Plasmodesmata

Answer 17

connects cells via cytoplasm filled canals which pass through cell walls.

Question 18

cell surface membrane

Answer 18

absorption of amino acids

Question 19

cell wall

Answer 19

protects the cell and keeps it upright

Question 20

what are the similarities between mitochondria and chloroplasts?

Answer 20

Both have double membrane
Both have highly folded inner membranes
Both have a circle of DNA for self-replication
Both have ribosomes
Both produce ATP

Question 21

what are the differences between mitochondria and chloroplasts?

Answer 21

Mitochondria have cristae, but chloroplasts have thylakoid membranes.
Chloroplasts contain photosynthetic pigments to absorb light energy, mitochondria
do not.
Mitochondria have an inner matrix, but chloroplasts have a stroma.

Question 22

Prokaryotic cells?

Answer 22

don’t have membrane bound organelles in their cells - no nucleus, rough endoplasmic reticulum,golgi body,mitochondria or chloroplasts

Question 23

compare eukaryotic and prokaryotic cells

Answer 23

prokaryotic cells =

small 1 -10 nanometres
ribosomes are smaller and free in cytoplasm
no membrane bound organelles
DNA = free in cytoplasm
no nuclear envelope

eukaryotic cells =

big 1 -100 nanometres
ribosomes = larger and bound to the rough endoplasmic reticulum
membrane bound organelles = present
DNA contained with the nucleus
nucleus has double membrane

Question 24

why don’t viruses fit the cell theory?

Answer 24

they have no cell membrane, no cytoplasm, no
organelles and no chromosomes. and can only reproduce with the help of a host cell.

Question 25

Atoms tissues?

Answer 25

Atoms are arranged into molecules
moleucules form cells
cells work together to form tissues
tissues form organs and organs form tissues

Question 26

epithelial tissue

Answer 26

type of tissue forms a continuous layer, covering or lining the internal or external surfaces of the body. cells sit on a basement membrane and vary in shape and complexity.

Question 27

examples of epithelial tissue

Answer 27

cuboidal epithelium - lines kidney tubules and small intestine - cube shaped

ciliated epithelium - composed of cells which transport substances like mucus in the bronchi and ova in the oviducts. cilia move and sweep substances along. cells = obular

squamous epithelium - consists of flattened cells on a basement membrane . form the walls of the alveoli and line bowman’s capsule in the kidney nephron.

Question 28

Muscle tissue

Answer 28

comes in 3 main types- each w a different structure and function

skeletal muscle - attached to bones and moves the skeleton

Question 29

connective tissue

Answer 29

they connect support or seperate tissues and organs

Question 30

examples of connective tissues

Answer 30

areolar
collagen
ligaments
adipose

Question 31

what are organs?

Answer 31

comprised of several tissues working together performing a specific function

Question 32

what are organ systems?

Answer 32

group of organs working together with a particular role

Question 33

how to calculate the true size of a structure from magnified image?

Answer 33

measure the A to B with ruler in mm
divide this by the magnification
then multiply by 1000 to convert mm to micrometres
give your answer to 3 sig figs

Question 34

units to remember

Answer 34

1000 nanometres = 1 micrometre
1000 micrometres = 1 milimetre
1000 milimetres = 1 metre
1000 metres = 1 kilometre