2.1.1 EUKARYOTES

Question 1

Eukaryote organelles

Answer 1

nucleus, nucleolus, nuclear envelope, rough and smooth endoplasmic reticulum (ER), Golgi apparatus, ribosomes, mitochondria, lysosomes, chloroplasts, plasma membrane, centrioles, cell wall, flagella and cilia

Question 2

3 functions of nucleus

Answer 2

Organelle stores DNA (instructions for protein synthesis)
controls cell activity to regulate gene expression
involved in transcription to produce mRNA for protein synthesis

Question 3

nucleus structure

Answer 3

nuclear membrane with nuclear pores spanning it
surrounding the nucleoplasm which holds the nucleolus and chromatin

Question 4

nuclear membrane

Answer 4

made up of double lipid bilayer
surrounds nucleus
barrier from cytoplasm preventing unwanted substances in nucleus
has nuclear pores which selectively allow stuff like proteins through

Question 5

nucleolus

Answer 5

dense sphere in nucleus
made up of RNA and proteins
- it transcribes and processes rRNA
- assembles rRNA into ribosome
- which is then transported into cytoplasm for protein synthesis

Question 6

nuclear pore

Answer 6

allows needed substances in (steroid hormones) and out (eg mRNA) of nucleus

Question 7

Rough endoplasmic reticulum structure

Answer 7

System of flattened membrane (cisternae)
Contains cisternae fluid
coated with ribosomes

Question 7

RER function

Answer 7

RER’s ribosomes translate mRNA into amino acids, which are then assembled into polypeptides
RER modifies proteins for use in the cell.
RER checks proteins for proper folding and formation
protien is pinched off from rer into vesicle and moves to golgi

Question 7

Smooth endoplasmic reticulum structure

Answer 7

cisternae flattened membranes that have fluid filled cavities

Question 8

SER function

Answer 8

lipid-synthesis
cholestrol/lipids/steroid hormones

Question 9

golgi apparatus structure

Answer 9

stacked membrane-bound, flattened sacs

Question 10

golgi appartus function

Answer 10

modifies proteins (adds glucose for glycoprotein, adds lipid for lipoprotein, folds into 3d shape)
then these proteins are packaged into vesicles and pinched off to be stored in cell or moved to plasma membrane

Question 11

mitochondria structure

Answer 11

rod shaped
surrounded by two membranes (inner membrane is highly folded into cristae)
it is filled with fluid-filled matrix
(in microscope lines go up down the cell)

Question 12

mitochondria function

Answer 12

site of ATP production during aerobic resp
self-replicating so it can make more if needed
lots in muscle/liver cells/neurotransmitters where energy is most needed

Question 13

chloroplast structure

Answer 13

found only in plant cells
surrounded by double membrane
inner membrane is continous stacks of flattened membrane-sacs called thylakoids
each stack of thylakoids is called granum
the fluid inside chloroplast is stroma

Question 14

chloroplast function

Answer 14

site of photosynthesis
1- light trapped by chlorophyll to make ATP in grana
2- h reduces co2 using energy from ATP to make carbs

Question 15

large permanent vacuole structure

Answer 15

surrounded by tonoplast membrane
filled w cell sap

Question 16

large permanent vacuole function

Answer 16

filled w water and solutes to maintain cell stability
makes cell turgid when full of water

Question 17

lysosome structure

Answer 17

small bags formed by golgi apparatus
surrounded by single membrane
contains hydrolytic enzymes
has wbc’s

Question 18

lysosome function

Answer 18

engulfs old cell organelles and digests them to return them as digested components to be reused

Question 19

cilia structure

Answer 19

protrusions from cell
surrounded by plasma membrane
contains microtubules
formed from centrioles

Question 20

cilia function

Answer 20

moves mucus in your esophagus to clear and protect airway
protects lungs from pathogens by trapping them in mucus

Question 21

undulipodia structure

Answer 21

sperm tail

Question 22

ribosomes structure

Answer 22

80s = eukaryotes
made of rRNA
made in nucleolus

Question 23

ribosomes function

Answer 23

protein synthesis

Question 24

centrioles structure

Answer 24

consists of two bundles of microtubules at right angles to each other the microtubules are made of tubulin arranged in cylinder

Question 25

centriole function

Answer 25

before cell division, spindle made of tubulin thread forms from centriole chromosomes attatc to middle part of spindle and motor proteins walk along tubulin thread pulling chromosomes to opp ends centriolesform cilia and undelopodia: centrioles multiply and line upbeneath plasma membrane microtubules then sprout outwards from each centriole forming cilium/undelepodium

Question 26

cytoskeleton structure

Answer 26

rod like microfilaments made of subunit of protein actin microtubules made of tubulin cytoskeletal motor proteins are mlecular motors they also allow hyrolysis of ATP

Question 27

cytoskeleton function

Answer 27

microfilaments: intermediate filaments anchors nucleus in place in cytoplasm provides tensile strength in cell microtubules: forms mitotic spindle fibres, cilia, flagella assists in cell-cell signaling

Question 28

cellulose cell wall structure

Answer 28

outside the plants plasma membrane made of bundles of cellulose fibres Cellulose molecule is polymer made of b-glucose molecules form a H bond with each other forming larger microfibrils These overlap, forming mesh like structure of cell wall

Question 29

cellulose cell wall function

Answer 29

high tensile strength: prevents cell bursting when turgid permeable to small molecules: allows water in needed for photosynthesis

Question 30

plant cell vs animal cell

Answer 30

plants have: cellulose cell wall large permanent vacuole chloroplast animal cells: lysosome centrioles

Question 31

how is the structure of a mitochondrion adapted for its function

Answer 31

Large surface area due cristae to allow more ATP production Matrix contains enzymes for aerobic respiration Double membrane allows compartmentalization for efficient ATP synthesis