Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

emergency biology > aaa > Flashcards

aaa Flashcards

1
Q

light dependent reaction

A

chlorophyll (ps2) absorbs light energy

excites electron - released from ps2 - photoionisation
water split using light energy - photolysis
electrons from water replace electron

high energy electron travels down electron carriers - loses energy for H+ pump - stroma to thylakoid lumen

electrons ps2 replace electrons used by ps 1

electrons ps1 reduce NADP

H+ diffuse into stroma via ATP synthase - photophosphorylation

oxygen diffuses from chloroplast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

light independent reaction

A

stroma of chloroplast

ribulose bi-phosphate combines with co2 = 2x glycerate phosphate catalysed by rubisco

glycerate phosphate reduced to triose phosphate using electron from NADPH
ATP hydrolysis - energy

1/6 trios phosphate - leaves cycle to form glucose
5/6 form ribulose phosphate

ribulose phosphate phosphorylated to ribulose biphosphate using ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

glycolysis

A

glucose phosphorylated twice - fructose diphosphate
- ATP hydrolysed Pi added to glucose

this activates glucose

fructose diphosphate converted - triose phosphate
triose phosphate oxidised to pyruvate - electrons removed reduce NAD
ADP phosphorylated - ATP - substrate level phosphorylation
= 2ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

link reaction

A

mitochondrial matrix

pyruvate decarboxylated and dehydrogenated = acetyl group

electrons reduces NAD

acetyl group joins coenzyme A = acetyl coA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

krebs cycle

A

x2 - mitochondrial matrix

acetyl coA + 4c = 6C = decarboxylation and dehydrogenation
NAD reduced - co2 - coenzyme A released

substrate level phosphorylated - ATP
electron removed - 4C compound
FAD reduced

electron removed from 4C compound - NAD reduced

fully oxidised glucose - all 6C released as CO2 and all 12H stored on reduced co-factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

oxidative phosphorylation

A

NADH binds to first electron carrier in ETC - dehydrogenated to NAD
NAD - glycolysis, link reaction, krebs cycle

high energy electron from NADH passed down ETC - loses energy - pump protons against chemiosmotic gradient - matrix to inner lumen

electrons combine with oxygen - water
oxygen - terminal electron acceptor

H+ diffuse from inner membrane space to matrix via ATP synthase - changed 3 str of enzyme - active site for ADP+Pi to combine - oxidative phosphorylation

NADH joins first ETC pump - activated 3H+ pumps - 3ATP per NADH
FADH - second ETC pump - activates 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

biomass

A

mass of carbon or dry mass of tissue per given area - seasonal moisture changes

  • productivity and diversity of ecosystem
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

collecting animal cample

A

create grid

random number generator

quadrat

collect organic material

repeat for average

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

bomb calorimeter

A

burn organic material

energy released heats surrounding water

increase in water temp allows to calculate energy content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

chemical energy stored in biomass

A

gpp = npp + r

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

net production of consumers

A

N = I - (F+R)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

phosphorus cycle

A

released into soil + water - weathering as phosphate ions

phosphate ions taken up by plants - roots or absorbed by water by algae - transferred to consumers by feeding

phosphate ions - waste products and dead organisms - release into soil or water
- saprobiont decomposition

phospholipid+3H2O breaks ester bond - glycerol, fatty acid and a phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nitrogen cycle

A

nitrogen fixation
- atmospheric nitrogen gas converted nitrogen-containing compounds
- nitrogen-fixing bacteria (nitrogen to ammonia)
forming ammonium ions -> plants

ammonification
- proteins and nucleic acids in dead organic matter converted to ammonium ions by saprobionts

nitrification
- ammonium ions converted (oxidised) into nitrite ions by nitrosomonas
- nitrite ions converted to nitrate ions by nitrobacter
- bacteria are chemo-autotrophs
- bacteria outcompete with plants for ammonium ions - plants only have access to nitrate ions

  • faster in aerobic conditions

denitrification
- nitrate ions reduced to nitrogen gas by denitrifying bacteria - faster in anaerobic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

receptors

A

pacinia corpuscle
- receptors only respond to specific stimuli

pressure on capsule - formation of lamella

pressure transmitted to nerve ending

pressure gated Na+ channels in cell membrane of nerve ending open

Na+ diffuses in - depolarisation - generator potential
- more pressure, more open channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

rods

A

light causes rhodopsin to break down - sheets of membrane with photosynthetic pigment
causing production of generator potential
release of neurotransmitter to bipolar neuron
if enough neutransmitter Na+ release for action potential

connected in groups - spatial summation - low light but low acuity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

photoreceptors

A

specialised cells in eye to detect light and covert to neural signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

cones

A

individual - bright light - high acuity

3 pigments - trichromatic

fovea - area in centre of eye with only cone cells - high acuity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

control of heart

A

myogenic - generates own contractions

right atrium - sino atrial node
sino atrial node at regular intervals generates waves of electrical activity - spreads through walls of atria so atria contracts

passes through artio-ventricular node - ventricles fill

electrical activity travels rapidly via bundle of his to base of heart - spread at bottom causing contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

speed of heart

A

sympathetic nerve - accelerator nerve - releases neurotransmitter noradrenalin into heart surface, adrenal receptors - SAN more often

parasympathetic nerve - vagas nerve - acetylcholine - cholinergic receptors, SAN less often

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

synaptic transmission

A

actin potential travels down axon - arrives at synaptic knob triggering calcium inrush

vesicles containing neurotransmitter move to presynaptic membrane - exocytosis

neurotransmitter diffuses and binds to receptors causing sodium channels to open - if enough sodium diffuses in - threshold

recovery - enzymes hydrolyse neurotransmitter and reabsorb into synaptic knob for resynthesis
- neurotransmitter removed by reabsorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

myelinated neurones

A

ion exchange - sodium in, potassium out - only in nodes

  • saltatory conduction - depolarisation jumps from node to node
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

restriction endonuclease

A

enzymes cut a DNA molecule at a specific set of bases - recognition sequence - breaking phosphodiester bonds between adjacent nucleotides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

reverse transcriptase

A

adds DNA nucleotides to mRNA molecule which forms cDNA - then enzyme destroys mRNA molecule - second DNA strand is built by enzyme DNA polymerase producing complete DNA fragment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

gene machine

A

DNA sequence - starting from protein

amino acid sequence of protein is identified - using this, complementary DNA sequence can be identified

DNA sequence entered into computer which checks if DNA safe then gene machine assembles short strands (~20-100nt) of DNA or RNA one nucleotide at a time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

in vivo

A

inside a living organism

dna fragment placed in plasmid (vector) - carries the DNA fragment into host cell

restriction endonuclease - DNA fragment has sticky ends - same cuts plasmid so complimentary = joins by h bonds

DNA ligase binds nucleotides on fragment and plasmid - catalyses formation of phosphodiester bonds

recombinant plasmid forms

promoter and terminator need to be added

26
Q

in vivo - transformation

A

inserting into bacterium - cell membrane
plasmid - polar, hydrophilic and negatively charged

add calcium ions - positively charged - takes plasmid closer to membrane

heat shock - holes in membrane

27
Q

PCR

A

polymerase chain reaction

  • denaturation - 95C - high heat to break H-bonds in DNA fragment and make DNA template strand single stranded
  • annealing - cooling to allow primers join to complimentary bases at end of each strand by H bonds
  • polymerisation - temp increases - all DNA nucleotides bind to exposed template and thermostable DNA polymerase join them by phosphodiester bonds
28
Q

DNA probes

A

short single stranded piece of DNA complimentary to a specific gene sequece

DNA hybridisation - when DNA probe attaches to complimentary DNA sequence

labelling probes - radioactive or fluorescent

29
Q

DNA probes - hybridisation

A
  1. produce copies of labelled DNA probes - pcr
  2. heat up sample - H-bonds break - DNA strands seperate
  3. add DNA probes and cool mixture - H-bonds form
  4. wash DNA sample with ethanol solution
  5. check if hybridisation has occurred
30
Q

genetic fingerprinting

A

variable number of tandem repeats - VNTRs
- repetitive non-coding DNA sequences directly next to each other

  1. collect DNA sample
  2. PCR to amplify DNA
  3. restriction enzymes to produce VNTR DNA fragments
  4. VNTR fragments separated by gel electrophoresis
  5. add alkali to separate VNTRS to single strands
  6. add complimentary DNA probes to identify VNTRs
  7. compare patterns
31
Q

DNA sequencing

A

finding nucleotide sequence for gene or whole genome

human genome project - 2003

proteome - set of proteins in organisms

we have non-coding DNA and regulatory proteins so hard to find proteome

32
Q

Gel electrophoresis

A
  • to separate molecules of DNA, RNA or proteins
    DNA and RNA - mass = length
    AA - mass = R group or number of aa or charge

DNA negative charge due to phosphate group

DNA fragments loaded into get at top
electrodes connected -ve at top and +ve at bottom
DNA move from negative to positive
short = fast
stain gel to visualise DNA

33
Q

mutations

A

addition - one or more DNA nucleotide added = frameshift or addition of aa

duplication - one or more bases duplicated = frameshift or addition of aa

inversion - set of nucleotides separate from a DNA sequence and rejoin in inverse order

translocation - set of nucleotides separate from sequence in one chromosome and attach to a different chromosome - changes gene expression

34
Q

gene therapy

A

replacement of non-functional allele with functional allele - for monogenic diseases

somatic gene therapy - introducing good allele to body cells - own symptoms cured but gametes contain bad allele

germ-line gene therapy - good allele introduced to gamete - illegal

35
Q

transcription factors

A

proteins that move from cytoplasm of eukaryotic cell to nucleus to stimulate or inhibit transcription

each transcription factor has a complimentary binding to particular base sequence in DNA - can be active or inactive

  • important for induced pluripotent - altering unipotent cells to enable translation of additional genes
36
Q

epigenetics

A

heritable changes in gene function without genes to the base sequence

DNA-histone complex - tight = gene hidden to transcription hard to take place as transcription factors and DNA polymerase cannot reach

epigenome - chemical tags - attach to DNA and histones - determines shape - added or removed by environmental factors

acetylation - increase - stimulation
methylation - descrease - stimulation

37
Q

treating disease using epigenetics

A

target enzymes as both acetylation and methylation involve enzymes

responsible for adding or removing chemical tag

eg inhibit the enzyme responsible for adding methyl groups

must ONLY target disease cell

38
Q

RNAi

A

RNA interference - translation inhibition by RNA

microRNA - miRNA - binds to protein complex in cytoplasm - RNA-induced silencing complex - then binds to complementary base pairs on mRNA - prevents translation by preventing ribosome from attaching or enzyme destroys mRNA

SiRNA - cell naturally produces short double stranded RNA - one strand complimentary to mRNA - enzyme called DICER cuts into shorter fragments - siRNA - same as miRNA

39
Q

tumour suppressor genes

A

code for proteins that slow or prevent cell division

code for proteins that repair mistakes in DNA

code for proteins that tell abnormal cells to die

mutation
deletion mutation - changes aa sequence - protein cannot function correctly

proto-congenes - stimulate cell division
oncogene - mutated proto-oncogene

40
Q

role of eostrogen

A

oestrogen - hormone produces by ovary and fat cells in breast tissue

passes through cell surface membrane and initiates transcription by binding to receptor on transcription factor - changes 3 str to comp with DNA - initiates transcription

menopause - fat cells increase oestrogen production

41
Q

too high blood glucose

A

stimulates B cells in islets of Langerhans in the pancreas - these release insulin into the blood

insulin binds to insulin receptor proteins on cell surface membrane of liver and muscle cells - insulin receptor 3str change - series of reactions

vesicles containing glucose carrier proteins move and added to membrane - exocytosis - glucose transported into cell from blood - facilitated diffusion - enzyme glycogen synthase activated by phosphorylation - glycogenesis

insulin no longer binds with receptor - cell membrane loses glucose carrier and enzyme inactive
B cells stop secreting insulin

42
Q

too low blood glucose

A

a cells - islets of langerhans - release protein hormone glucagon into blood - binds with glucagon receptor proteins on cell surface membrane of liver and muscles - changes 3str - activates enzyme adenylate cyclase

adenylate cyclase converts ATP to cAMP - secondary messenger causing reactions involving kinase enzyme to activate other enzymes in cell

  • hydrolysis of glycogen to glucose - glycogenolysis
  • glucose synthesised from non-carbohydrate sources eg fatty acids - gluneogenesis
  • more glucose - transport proteins introduced so glucose can leave cell into blood

glucagon no longer binds to receptor, membrane loses glucose carrier proteins, enzymes inactive a cells stop secreting glucagon

43
Q

gross muscle structure

A

sarcomere - section inside myofibril made up of a vertical stack of atleast 4 thin and 1 thick

m line - middle of sarcomere - thick
z line - mid point between m lines - thin
I band - where only thin
A band - thick and thin
H zone - only thick

44
Q

depolarisation of muscle fibre

A

neuromuscular function

nerve impulse passes from motor neurone to muscle fibre - triggers depolarisation - spreads across whole muscle fibre

  • depolarisation reaches sacroplasmic endoreticulum - wrapped around muscle fibre’s myofibrils
  1. depolarisation causes sacroplasmic reticulum to release calcium ions into myofibrils
45
Q

actin

A

thin filament - wrapped with tropomyosin protein chain - binding sites under - specific for myosin heads

calcium ions - tropomyosin changes shape exposing binding sites

actomyosin bridge

46
Q

myosin

A

active site on myosin head - ATP hydrolysis
ATPase

47
Q

sliding filament mechanism

A
  • calcium ions trigger tropomyosin to move away from binding site
  • actinomyosin bridge forms
  • ADP and Pi released from myosin head - power stroke
  • ATP molecule binds to myosin - bridge broke
  • ATP hydrolysis
  • starting position reading to bind again
48
Q

autosomal linkage

A

two or more genes are on the same autosomal chromosome

49
Q

epistasis

A

interaction of different loci on the gene

one gene locus affects the other gene - can mask or suppress expression

recessive - 9:3:4
dominant - 12:3:1

50
Q

hardy-weinberg equation

A

used to estimate the frequency of alleles in a population - see whether change in allele frequency is occurring in population over time

  • assumed no mutation
  • large population
  • no selection

p + q = 1.0
p^2 + 2pq + q^2 = 1
p = frequency of dominant allele
q = frequency of recessive allele
p^2 = frequency of AA
2pq = frequency of Aa
q^2 = frequency of aa

51
Q

primary succession

A

area previously devoid of life - colonised by community of organisms

colonised by pioneer species - as organisms die, they decompose by microorganisms - makes environment less harsh - more suitable for complex organisms

richer in mineral over time - larger plants
climax community - final stage - self-sustaining stable community

52
Q

secondary succession

A

previously colonised area has been cleared eg forest fire - soil layer already present

53
Q

types of stem cells

A
  1. Totipotent - can form any type of cells in the body plus extra embryonic cells.
  2. Pluripotent - these cells can form any cell type in the body, however cannot form extra embryonic cells. They are also found in the early stages of an embryo. These are often used in replacing damaged tissues in human disorders.
  3. Multipotent - can differentiate into other cells types but are more limited e.g. the cells in the bone marrow and umbilical cord.
  4. Unipotent - these cells can only differentiate into one type of cell.
54
Q

osmoregulation

A

sensory neurones - osmoreceptors monitor water potential

if water potential decrease - nerve impulse - sensory neurones to posterior pituitary gland - release antidiuretic hormones which causes kidneys to reabsorb more water

55
Q

effect of ADH on kidneys

A

ADH binds to receptor proteins in the cell surface membranes of the collecting duct cells

aquaporins are phosphorylated - activates them

vesicles move towards luminal membranes of collecting duct cells

vesicles fuse with luminal membranes

water moves through aquaporins down water potential gradient

56
Q

structure of a nephron

A

Within the Bowman’s capsule of each nephron is a structure known as the glomerulus
Each glomerulus is supplied with blood by an afferent arteriole (which carries blood from the renal artery)
The capillaries of the glomerulus rejoin to form an efferent arteriole
Blood then flows from the efferent arteriole into a network of capillaries that run closely alongside the rest of the nephron
Blood from these capillaries eventually flows into the renal vein

57
Q

ultrafiltration

A

arterioles branch off renal artery to nephron - form glomerulus inside bowman’s capsule

capillaries get narrower - increases pressure of blood which forces smaller molecules out of the capillaries into the bowman’s capsule - filtrate

blood passes through glomerular capillaries - holes in endothelial cells and gaps between podocytes allow substances dissolved in blood plasma to pass into bowman’s capsule - aa, water, glucose

58
Q

how ultrafiltration occurs

A

due to differences in water potential between plasma in glomerular capillaries and filtrate in bowman’s capsule

59
Q

selection reabsorption

A

only substances body needs - most reabsorption in proximal convoluted tubule
- microvilli, many co-transporter proteins, mitochondria

  • sodium-potassium pumps use ATP from mitochondria to pump sodium ions out of proximal convoluted epithelial cells into blood
  • sodium ions move passively down concentration gradient from filtrate to epithelial cells - protein co-transporter molecules in membrane which also bring glucose and aa into cell
  • transport proteins in basal membrane allow solutes to diffuse down conc gradient from epithelial cells into blood
60
Q

reabsorption of water and salts

A
  • filtrates goes through loop on henle - salts reabsorbed by diffusions
  • water follows by osmosis
  • after necessary reabsorption - filtrate leaves nephron

emergency biology (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions