module 2.1

Question 1

plasma membrane?

Answer 1

phosolipid by layer that controls entry/exit.

Question 2

nucleus?

Answer 2

• has a nucleolus (contains RNA & makes ribosomes)
• MRNA leaves through pores
• nuclear envelope
• nuclear pores (substances to enter/leave)
• inside nucleus= chromatin (chromosomes) found here

Question 3

RER?

Answer 3

• doubler membrane with cisternae for transporting molecules

- contains ribosomes for protein synthesis

Question 4

SER?

Answer 4

-synthesise cholesterol and lipids

Question 5

Golgi?

Answer 5

• receives proteins from ribosomes in a vesicle(small membrane sac)
• proteins are folded, processed & sent to membrane in vesicle.

Question 6

Lysosomes?

Answer 6

-bind to old organelles & pathogens to release enzymes and digest them.

Question 7

Centriole?

Answer 7

• animal cells only
• involved in cilli & pseudopodia formation (2.5)
• involved in cell division (2.6)

Question 8

mitochondria?

Answer 8

• site of aerobic respiration

- membrane bound organelle

Question 9

what are the 3 plant only organelles?

Answer 9

cell wall, permanent vacuole, chloroplasts

Question 10

PLANTS ONLY- chloroplasts?

Answer 10

• site of photosynthesis
• membrane bound organelle
• high internal surface area for photosynthesis

Question 11

PLANTS ONLY-permanent vacuole?

Answer 11

• membrane bound( called tonoplast)
• contains sap
• maintains turgidity (firmness)

Question 12

PLANTS ONLY- cell wall?

Answer 12

• made out of cellulose(sugar)

- protects the cell

Question 13

what is the cytoskeleton?

Answer 13

a collection of filaments and tubules that give the cell its shape and structure + allows movement within a cell

Question 14

state necessary things about microfilaments

Answer 14

polymers of actin
provide shape and structure
very small
7nm diameter

Question 15

state necessary things about microtubules

Answer 15

polymers of tubulin
provide a transport network for KINESINS( motor proteins) to pull vesicles + organelles around the cell
used in mitosis and flagella
18-30 nm

Question 16

what is a stage micrometre

Answer 16

standard sized ruler to calibrate microscopes

Question 17

what is an eye graticule

Answer 17

standard sized ruler in the eyepiece that remains in focus at all times. used for measuring cells.

Question 18

compare eukaryotic cells and prokaryotic cells (6)

Answer 18

eukaryotic:
\_\_\_\_\_\_\_\_\_\_
true nucleus
membrane bound organelles(eg golgi)
larger (usually)
animal/plant/fungi/protists

Prokaryotic
\_\_\_\_\_\_\_\_\_\_
no nucleus
no membrane bound organelles
smaller
bacteria+archea

Question 19

prokaryotic cells:

pilli?

Answer 19

attaching to other surfaces or cells

Question 20

~prokaryotic cells:

plasma membrane

Answer 20

~surrounds cytoplasm

Question 21

prokaryotic cells:

no nucleus/ loose dna

Answer 21

continuous loop, no histones

Question 22

prokaryotic cells:

ribosomes

Answer 22

smaller

no rer

Question 23

prokaryotic cells:

cytoplasm

Answer 23

no cytoskeletal structures

Question 24

prokaryotic cells: wall around it name??

Answer 24

peptidoglycan wall (protein)

Question 25

prokaryotic cells: plasmids?

Answer 25

small circle of genetic material

Question 26

prokaryotic cells: flagellum

Answer 26

mobility

Question 27

name all the structures in prokaryotic cells:

Answer 27

- pilli - no nucleus, loose DNA - cytoplasm - plasma membrane - ribosomes - plasmids - flagellum - no membrane bound organelles - peptidoglycan wall (protein) - protective waxy capsule surrounding cell wall

Question 28

how can bacteria pass on genetic material between organisms? (1)

Answer 28

pilus draws bacteria together

Question 29

how can bacteria pass on genetic material between organisms? (4)

Answer 29

plasmids can be passed from one bacterium to an adjacent bacterium. This naturally occurring phenomenon allows beneficial traits to spread quickly. -used to produce desired proteins

Question 30

what is the Endosymbiotic theory

Answer 30

explains how early eukaryotic cells consumed respiring bacteria+ photosynthesising bacteria for mutual benefits.

Question 31

what is millimetres to micrometres?

Answer 31

1mm= 1000um

Question 32

what is micrometres to nanometers?

Answer 32

1um=1000nm

Question 33

coordination between organelles- state how proteins are made

Answer 33

1. a gene is copied into a molecule of MRNA (messenger RNA). This is called TRANSCRIPTION. 2. the mRNA leaves the nucleus via a pore and travels to the ribosome on RER. 3. The mRNA is read by a ribosome in triplet code to make a primary structure protein, this is called TRANSLATION. 4. The primary structure protein is budded off the RER in a vesicle and moved to the golgi body. 5. At the golgi, the primary structure proteins are folded into secondary/tertiary/quaternary structure formation. Other components are added to the protein. 6. The finished protein is budded off the golgi into a vesicle and moved to the plasma membrane. 7. Vesicle merges with plasma membrane and the proteins released from the cell. This is called EXOCYTOSIS.

Question 34

Coordination between organelles:7 steps of making proteins

Answer 34

1. A gene is copied into a molecule of mRNA(TRANSCRIPTION) 2. The mRNA leaves the nucleus via a pore and travels to the ribosome on RER. 3. The mRNA is read by a ribosome in triplet code to make it a primary structure protein. 4. The primary structure protein is budded off the RER in a vesicle and moved to the Golgi body. 5. At the golgi, the primary structure protein is folded into secondary/tertiary/ quaternary formation. 6. The finished protein is budded off the golgi into a vesicle and moved to the plasma membrane. 7. Vesicle merges with plasma membrane and the protein is released from the cell (EXOCYTOSIS)

Question 35

state general things about optical microscopes... red and mag included

Answer 35

rely on lenses to focus a beam of light. mag up to x1500. and res (0.2um)

Question 36

advantages of optical microscopes

Answer 36

cheap, easy to use, specimen can be alive

Question 37

disadvantages of optical microscopes

Answer 37

low mag, low res

Question 38

advantages of tems

Answer 38

high level mag/res | fine detail can be observed

Question 39

disadvantages of tems

Answer 39

large, expensive, specimens have to be dead. skills and training needed.

Question 40

advantages of sems

Answer 40

3D image given, high mag, depth of field given

Question 41

disadvantages of sems

Answer 41

black and white image, expensive, large, specimens have to be dead

Question 42

how do laser scanning microscopes work

Answer 42

use laser light to scan an object point by point and assemble it by computer

Question 43

advantages of laser scanning microscopes

Answer 43

can focus on structures at diff depths within a specimen so can observe whole living specimens

Question 44

disadvantages of laser scanning microscopes

Answer 44

costly, relatively small field of vision

Question 45

state 4 similarities and differences between bacterial cells (prokaryotes) and fungal cells (eukaryotes)

Answer 45

- both have ribosomes in the cytoplasm - only fungi have a membrane bound nucleus - bacteria have plasmids, fungi do not. - both have cell walls. Fungal is made of CHITTIN and bacteria is PEPTIDOGLYCAN.

Question 46

uses of light microscope, TEM, SEM, laser scanning!!

Answer 46

light microscope- whole cells and tissues TEM- organelles SEM- cell surfaces laser scanning- an object at a certain depth within a cell

Question 47

resolution and magnification of: light microscope; TEM; SEM;

Answer 47

light microscope; x1500 |200nm (0.2um) TEM; x500000 | 0.2nm SEM; x100000 | 0.2 nm

Question 48

how do you find the value of one eyepiece division

Answer 48

1000/total magnification =___um

Question 49

why do specimens need to be stained

Answer 49

to make them visible, to increase contrast

Question 50

2 processes inside cells that rely on cell movement

Answer 50

- chromosomes in cell division | - exocytosis