OCR A Flashcards
stem cell
a cell that is, unspecialised / not differentiated ; capable of, division / mitosis ; able to, differentiate / specialise / become other cell types ;
place that contains stemcells in plants
cambium / meristem / early embryonic cells ;
need fo mitosis
growth (of tissue / organism) ; replace (cells) / repair (tissues) ; asexual reproduction/cloning / producing genetically identical cells ; maintain chromosome number in all cells ;
advantages of stm cells
1 greater availability of cord cells / more likely to find donors;
2 easier to harvest / no pain for donor ;
3 cells at earlier stage of development ;
4 can be stored for future, use/repair / gene therapy, of donor ; 5 slightly mismatched cord cells work (almost) as well as marrow cells ;
increased probability of survival
cell signalling
communication between cells / AW ;
cell, recognition / identification ; cells work together / coordination between action of different cells ; to trigger, response / reaction ( inside the cell) ;
2
phospholipid (bilayer) / phospholipid head ;
to act as a barrier (to, polar / charged, particles) / select what enters or leaves cell ;
protein / glycoprotein / intrinsic protein / protein channel / protein pump / transport protein / carrier protein
allow communication across membrane OR allow, polar / charged, particles to pass through membrane ;
cholesterol ;
stabilise the membrane OR maintain / affect / control / AW, fluidity OR reduces permeability to, polar / charged, particles ;
how glycolprotein acts a receptior
(receptor) specific shape / described ; complementary to (shape of), trigger / named trigger / communicating ; molecule ; (trigger / AW) binds / attaches to receptor ;
struvted asssocated witht the cytoplasm for cell movement
flagellum / cilium / microtubule / microfilament / undulipodium ;
processs that relys on cytoskeleton for movement
(movement inside cells of)
chromosomes / chromatids (in cell division) ; (cytoplasm in) cytokinesis ; organelles / named organelle ;
RNA (in protein synthesis) ; proteins ;
2
what happens if DNA not checked
mutation / faulty DNA produced / error in copying ; daughter cells will not receive identical genetic information ; proteins / (daughter) cells, not made / do not function ;
2
meiosis vs mitosis daughter cells
haploid / half genetic information / chromosome number is n ;
genetic information not identical / produces genetically different cells ; 4 cells produced ;
resolution
ability to see (two) objects (that are close together) as separate objects / AW ; see detail ;
tissure
collection / group, of cells (of one or more types) ; (cells), working together OR with, common / same, function ;
function of mesosome in prokaryotes
production of ATP ; aerobic respiration ;
adaptatyions of guard cells
A1 a vacuole ; E1 to take up water / to become turgid ;
A2 cell wall thicker on one side ; E2 causes, cell to bend / open stoma(ta) ;
A3 mitochondria ; E3 generates ATP (for active transport) ;
processes that occur during interphase
1 checking, genetic material / DNA / chromatin / chromosome(s) / genes, (for errors) ;
2 protein synthesis ;
3 synthesis / replication / increase in number of, organelles / named organelle ;
4 ATP production / respiration ;
5 cell growth / increase in cell, volume / size ;
two ways cell divisions differs in plants than animals
in plant
(cell) , plate / wall, forms (between new cells) ; idea of : cytokinesis starts from middle of cell ;
(only) occurs in meristem ;
no centrioles ;
AVP ;
2
roles of the cyto skeleton
1 provides, strength / stability / support (cell) ;
2 determines shape / changes shape / moves membrane (for endo / exocytosis) ;
3 movement of, organelles / named organelle / RNA / protein / chromosomes / chromatids ;
4 attachment to / hold, organelles / named organelle, in place;
5 make up, centrioles / spindle fibres ;
how is the neutrophil specialised
1 (many) lysosomes / vesicles containing enzymes ;
2 (many) microfilaments / microtubules OR ref to, extensive / well developed, cytoskeleton ;
3 (many) ribosomes / (a lot of) rough endoplasmic reticulum / (a lot of ) RER ;
4 (many) mitochondria ;
5 (lots of) Golgi ;
6 (many) receptor (sites) on, cell surface / plasma , membrane
how water passes through the csm
fit between (phospho)lipids / through (phospho)lipid (bi)layer ;
via, protein channels / protein pores / aquaporins ;
why plant cells nah burst when placed inside pure water
cell wall ;
provides strength / withstands (internal) pressure / prevents cell membrane over expanding / exerts pressure potential ;
limits uptake of water ;
function of the golgi
production of vesicles / packaging proteins ;
modification of / processing of / adding carbohydrate to , proteins ;
production of lysosomes ;
why nuclear envolpe has pores
allow movement (of substances) in or out of nucleus ;
correctly named substance (entering or leaving nucleus) ;
ref to correct destination of substance
function of lysosome
contain / release , lysins / lytic enzymes / hydrolytic enzymes / digestive enzymes ;
digest / break down , organelles / foreign objects / toxins / cells / pathogens ;
apoptosis / autolysis / described ;
organ
idea of more than one (type of) tissue ;
working together / performing a function(s) ;
active transport
(movement of substances) against / up , concentration gradient or from low to high concentration ;
using , ATP / (metabolic) energy ;
using a , transport / carrier , protein ;
componants of the csm
phospholipids ; proteins ; glycoproteins ; cholesterol ; glycolipids
two examples of AT in cells
(mineral) ions / salts / named e.g, (into) root hair (cell) ;
hydrogen ions (out of) companion cells ;
(mineral) ions / salts / named e.g, (across) endodermis ; sucrose out of sieve tube at sink ;
difference between magnification and resolution
magnification is the number of times larger the image is compared to the object ;
resolution is ability to, distinguish / differentiate between, two separate points OR the, level / degree, of detail that can be seen ;
function of the nuclear pores
allow communication between nucleus and cytoplasm or allow, molecules / named substances, to, enter / leave (the nucleus
features light microscope cant see
(named) membranes / phospholipid bilayer ; ribosomes ; Golgi ; endoplasmic reticulum / ER / RER / SER ; cytoskeleton / microtubules / microfilaments / spindle fibres ; centrioles ; vesicles / lysosomes ; mitochondria ;
three roles of membraines inside the cell
form / produce / make, compartments / organelles / named organelles (within a cell) / AW ;
isolation / AW, of, contents (of organelle) / substance / named substance / reactions / metabolic pathways ;
site for attachment of, enzymes / other named molecules / ribosomes ;
provide selective permeability / described ;
creation of, concentration gradients / specific environments / described ;
how vesicles moved from one place to the next
cytoskeleton / microtubule / microfilament ; provide, pathways / tracks, (for movement) ;
(vesicle) moves along, microfilaments / microtubule ;
microtubules, extended / broken down ;
uses, ATP / (metabolic) energy ; AVP
how are extracellular enzymes secreated from the cell
exocytosis ; vesicle fuses / merges ; (with), cell surface / plasma, membrane ;
discharging / releasing, enzyme / contents (to exterior
how proteins on the memebrane of vesicles ensure vesicle transported to right place
receptor found only on, correct / target, (named) organelle ; idea that: address protein provides a way of, labelling / identifying / recognising, the vesicle ; protein / has a specific shape ; (shape of) receptor and (address) protein are complementary
wy must gnetic material replicate before division
idea that: cells, genetically identical / have same DNA ;
so both (daughter) cells receive a full, copy / complement
homologous chromosome
1 one maternal and one paternal / AW ; 2 carry same genes ;
3 carry, same / different, alleles ; 4 (usually) same / similar, length ;
5 centromere in same position ; 6 same banding pattern ;
7 pair up in meiosis / form bivalent ;
squamous epitioal vs ciliated epitihelial
squamous acts as a surface
or
short (diffusion) pathway ;
alveoli
or
cheek lining
or
in blood vessels ;
ciliated move, mucus / AW
or
secrete mucus ;
bronchioles
or
bronchi
or
trachea
or
airways ;
why plant cells don’t lysis
1 cell (cytoplasm) has a lower water potential than (distilled) water / ORA ;
2 water moves (into cells) , down water potential gradient / from high to low ;
3 (water) enters the cell by osmosis ;
4 idea of: cell surface / plasma, membrane (of blood cell) weak so, bursts / cannot withstand pressure / haemolyses ;
5 idea of: (plant) cell wall , strong / provides support, so, does not burst / can withstand pressure ;
6 (plant) cell becomes turgid / turgidity increases, which reduces water uptake ; 4 max
QWC – two technical terms used in context and spelt correctly ;
how the root epidermal cells absorb minerals from soil and how are these cells specialised
1 active, transport / uptake ;
plus any two from: 2 cells have, extensions / hairs ;
3 thin cell wall ;
4 large / increased, surface area ;
5 many / more, mitochondria ;
6 (many) carrier proteins in cell (surface) membrane ;
how are the cells in a muliticellular organism organised
(cells) differentiate(d) / specialise(d) ;
(groups of) cells form tissue(s) ;
(groups of) tissues form organ(s) ;
(groups of organs) form organ system(s) ;
(group of) cells / tissues / organs / organ systems, work together / interact ;
named example of a tissue / an organ /an organ system ;
how csm contribute to cell singalling
communication between cells ;
idea that: molecule released by one cell, attaches to / causes change in, another cell ; release of signal molecule by, exocytosis / secretion OR described ;
idea that: proteins / glycoproteins / glycolipids, act as / have, receptors OR described ;
idea that: receptor / signal, is specific ;
idea that: shape of receptor and signal are complementary ;
idea that: attachment of signal molecule causes change (inside cell / on cell surface) ;
cell surface membrane allows entry of some signal molecules
describe structure of csm
phospholipid bilayer containing proteins ;
head / hydrophilic region, facing outwards OR tail / hydrophobic region, facing inwards ;
ref to intrinsic and extrinsic (glyco)proteins / described ;
idea of: glycoproteins / glycolipids, sticking out (of bilayer / membrane);
cholesterol, inside bilayer / between phospholipids
describe the effect of heigh temperatuees on csm
phospholipids / (named) molecules, vibrate more / move around more / have more kinetic energy ;
increases, size / number, of gaps, in membrane / between phospholipids ;
bilayer, becomes more fluid / melts ;
proteins / glycoproteins, denatured ;
describe the effect of heigh temperatures on csm
phospholipids / (named) molecules, vibrate more / move around more / have more kinetic energy ;
increases, size / number, of gaps, in membrane / between phospholipids ;
bilayer, becomes more fluid / melts ;
proteins / glycoproteins, denatured ;
two thinga plant cells have that animal cells dont
cellulose / cell, wall ;
chloroplast(s) ; starch grain(s) / amyloplast(s) ; large / permanent, vacuole ;
tonoplast ; plasmodesma(ta) ;
one thing found in animals and not plants
centriole / glycogen granule ; ACCEPT lysosomes, cilia, flagella
how cells work together to release proteins
1 nucleus , contains gene (for protein) / site of transcription / produces mRNA ;
2 ribosomes / rough endoplasmic reticulum / RER, site of, protein synthesis / translation ;
3 vesicles for transport (of protein) ;
4 Golgi (apparatus / body), processes / modifies / (re)packages, proteins ;
5 (vesicles) fuse to, cell surface / plasma, membrane
role of the cyto skeleton
1 (whole) cell, support / stability / scaffolding / maintain shape ;
2 movement of, cilia / flagella / undulipodia OR use of cilia / flagellum / undulipodium to move cell ;
3 changing shape of cell / cytokinesis / pseudopodia / phagocytosis / endocytosis / exocytosis / muscle contraction ;
4 (named) organelles, moved / held in place ;
5 movement of, chromosomes / chromatids / (m)RNA ;
the detailed structure of cells visible only with an electron microscope
ultrastructure
group of organs working together to perform an essential function
organ system
mitochondria
produces ATP
SER
SER / smooth endoplasmic reticulum transport / production / processing, of, fats / lipids / steroids / carbohydrates
why cant you see the mito with a light micro?
mitochondrion / cristae, too small ;
resolution (of light microscope), not high (enough) OR idea of only, 0.2µm / 200nm ;
wavelength of light too long ;
describe and explain the function of the components of the csm
A1 phospholipids form bilayer /described OR phospholipid hydrophobic tails pointing inwards and hydrophilic heads pointing out ;
F1 provide barrier to, large / polar / (named) molecules OR ions OR described ;
A2 proteins form, pores / channel / carriers OR extrinsic / intrinsic / transmembrane / described, proteins ; F2 for (active) transport / cotransport / facilitated diffusion OR enzymes ;
A3 cholesterol molecules fit, within bilayer / between phospholipid / between fatty acids / between (phospholipid OR hydrophobic) tails ; F3 stabilise membrane (structure) / regulates fluidity
A4 glycoproteins / glycolipids , on surface / sticking out from surface, (of cell surface membrane) ;
F4 cell signalling / receptor sites / adhesion / antigens / recognition OR stabilising (cell shape) ;
which component of the csm becomes more fluid as temp increases
phospholipid) bilayer ;
which component of the csm becomes more fluid as temp increases
phospholipid) bilayer ;
DNA codes for the structure of polypeptides.
State the role of messenger RNA (mRNA).
DNA codes for the structure of polypeptides.
State the role of messenger RNA (mRNA).
Explain why different enzymes are involved in each stage of the digestion process
enzymes are specific ; the , carbohydrate molecules / substrates , are different shapes ; active site and substrate are complementary ; so that substrate will fit / formation of ESC ; lock and key / induced fit ;
Explain why the activity of enzyme 2 falls to zero at pH 7.
pH much , higher / less acidic , than optimum (for enzyme 2) ; change in charge of active site ; hydrogen / ionic , bonds break ; tertiary structure / 3D shape / active site shape , altered ; enzyme / tertiary structure , denatured ; substrate no longer fits active site / ESC does not form
