cc2 - cell structure + organisation

Question 1

eukaryotic cell

Answer 1

cell containing true nucleus + membrane bound organelles

Question 2

structure of nucleus

Answer 2

surrounded by nuclear envelope - semi permeable + double membraned
nuclear pores - allow substance to enter/exit
dense nucleolus - (made of RNA + proteins) assembles ribosomes

Question 3

function if nucleus

Answer 3

contains DNA coiled around chromatin into chromosomes
coordinates cellular activity

Question 4

chromatin

Answer 4

DNA-protein complex in eukaryotic cells

Question 5

structure of mitochondria

Answer 5

surrounded by double membrane, mitochondrial envelope
folded inner membrane forms cristae (large SA)
fluid matrix contains mitochondrial DNA, respiratory enzymes, lipids + proteins

Question 6

function of mitochondria

Answer 6

site of aerobic respiration producing ATP

Question 7

structure of endoplasmic reticulum

Answer 7

series of flattened membrane bound sacs (cisternae) within cytoplasm, continuous w/ nuclear envelope
two types: rough er + smooth er

Question 8

function if smooth er

Answer 8

lipid synthesis

Question 9

function of rough er

Answer 9

many ribosomes attached for protein synthesis + transport

Question 10

structure of ribosomes

Answer 10

made of rRNA and proteins
found free in cytoplasm or associated w/ RER

Question 11

function of ribosomes

Answer 11

protein synthesis (translation)
- large subunit joins amino acids
- small subunit reads RNA

Question 12

structure of golgi body

Answer 12

planar stack of membrane bound organelles, flattened sacs
cis face aligns w/ rer
molecules processed in cisternae
vesicles bud of trans face via exocytosis

Question 13

fuction of golgi body

Answer 13

modifies + packages proteins for export
synthesises glycoproteins

Question 14

structure + function if lysosomes

Answer 14

fluid filled vesicles surrounded by single membrane, contains enzymes
role in phagocytosis, digest unwanted materials in cytoplasm

Question 15

structure of centrioles

Answer 15

cylindrical
organised into microtubules in a 9+0 pattern
found in pairs in centrosomes

Question 16

function of centrioles

Answer 16

migrate to opp poles of cells in prophase
involved in organisation of spindle fibres

Question 17

structure of chlorplast

Answer 17

disc shaped surrounded by double membrane
thyalkoids - flattened discs stacked to form grana
grana - contain photosystems w/ chlorphyll
intergranal lamellae - tubes attach thylakoids in adjacent grana
stroma - fluid filled matrix

Question 18

function of a chlorplast

Answer 18

site of photosynthesis

Question 19

structure of permanent vacuole in plants

Answer 19

surrounded by single membrane - tonoplast
contains cell sap (mineral ion, water, enzymes, soluble pigments)

Question 20

function of permanent vacuole in plants

Answer 20

controls turgor pressure
water storage
isolates harmful waste producst
maintains ph

Question 21

plasmodesmata

Answer 21

microscopic channels between plant cell wall that facilitate communication and symplastic transport

Question 22

prokaryotic cell

Answer 22

type of cell not containing any membrane bound organelles or a true nucleus

Question 23

structure + function of flagella in prokaryotic cells

Answer 23

long whip like protrusion made of flagellin
rotates to propel organism
sensory organ

Question 24

how is genetic information stored in prokaryotes

Answer 24

plasmids - small rings of DNA that carry non essential genes, exchanged between bacterial cells via conjugation
loop of DNA - circular DNA stored in nucleoid region of cell

Question 25

structure + function of pili in prokaryotic cells

Answer 25

hair like microfibres made of pilin that extend through cell wall enable attachment of bacteria to each other + to other surfaces

Question 26

structure + function of mesosome

Answer 26

infolds of cell memrbrane increase SA of cell, aiding cellular respiration

Question 27

function of capsule in prokaryotic cells

Answer 27

protective slimy layer helps cell retain moisture + adhere to other surfaces

Question 28

organelles found in both eukaryotic + prokaryotic cells

Answer 28

cell membrane cytoplasm with form of cytoskeleton ribosomes

Question 29

contrast eukaryotic + prokaryotic cells

Answer 29

prokaryotic: small, unicellular no membrane bound organelles circular DNA, not associated with proteins 70s ribosomes reproduce by binary fission peptidoglycan cell wall eukaryotic: large, often multicellular contain membrane bound organelles + true nucleus linear chromosomes associated with histones 80s ribosomes reproduce by sexual or asexual reproduction cellulose (plant), chitin (animal) cell wall

Question 30

contrast eukaryotic plant + animal cells

Answer 30

plant cell: cellulose cell wall large permanent vacuole contains chlorplasts no pseudopodia animal cells: no cell wall small temporary vacuoles (vesicles) no chloroplasts some may have pseudopodia

Question 31

light microscope

Answer 31

uses series of lenses to magnify visible light reflecting off a specimem

Question 32

magnification

Answer 32

number of times bigger an image appears compared to size of specimen

Question 33

how magnification of image is calculated

Answer 33

size of image magnification = ———————— size of specimen

Question 34

cell theory

Answer 34

cell is fundamental unit of all life forms new cells can be formed from existing cells cells contain genetic material which can be transferred to daughter cells

Question 35

virus

Answer 35

non living microorganism that consists of genetic material surrounded by a protein husk

Question 36

how viruses differ from prokaryotic + eukaryotic cells

Answer 36

virus: non living smaller + simpler in structure genetic material in form of DNA or RNA can only reproduce within a host cell no ribosomes prokaryotic + eukaryotic cells: living larger + more complex structure genetic material in form of DNA independent cell division, sexual or asexual contain ribosomes

Question 37

how are multicellular organisms organised

Answer 37

cells make tissue tissues make organ organs make organ system

Question 38

tissue

Answer 38

group of cell working together to carry out specific function

Question 39

organ

Answer 39

group of tissues working together to carry out specific function

Question 40

organ system

Answer 40

group of organs working together to carry out specific function