Topic 8 - Response Flashcards
Nature: genetic component
70% twins recognised
Identical twins agreement is greater - 41% more
Alleles are involved
Non-identical twins have genetic differences, identical twins are genetically the same
Because less than 100%, some other factor is involved
Recognising handwriting vs. faces of twins
Less of a gap between the results
fMRI during face identification: suggest why fMRI
Active areas have more oxygen/ oxygenated blood
Active areas involved in face recognition will be identified
Level of brain activity between identical twins and non-identical twins is compared: more areas showing activity in common in identical twins
To offer supportive evidence/improve validity of study
fMRI shows brain activity in real time
High resolution
Safer: fMRI does not use X-rays
Photosensitive pigment in plants
Phytochrome
Plant growth valid experiement
Standardise: water, mineral ion concentrations, light intensity, wavelength of light, CO2 conc., temp, pH, soil type
Study could be changed to produce a more accurate conclusion
Using shorter time intervals e.g. 1 hour intervals, only known between 12-15h, repeat with 12, 13 hours
Suggest one environmental cue other than day length stimulate flower production
Temperature Water availability the wavelength/quality of light Intensity of light edaphic factor
State the location of rhodopsin within a rod cell
Outer segment (internal membranes, inner membranes, vesicles)
Rhodposin responding to light
Opsin binds to the rod cell mebrane
Rhdoipsin bleaches
(ATP IS NOT USED)
Rhodopsin being reset
ATP used
(Opsin DOES NOT bind to the rod cell mebrane)
(Rhdoipsin DOES NOT bleach)
Medulla oblongata functions
Controls breathing/ heart rate
Involuntary muscles: swallowing, vomiting, sneezing
Cerebral hemisphere/ cerebrum frontal cortex function
Feel emotions
*GMO restriction enzymes - only one used
Cuts at a specific sequence of base (DNA sequence)
Generates sticky ends
so easier to join together
*Chemical which causes a gene to be ‘switched on’
The chemaical could be a transcription factor/ horone
Interations at bacterial cell surqfce memebrane
Transcription factor being activated e.g. transciprtion initiation complex formed, binds to trasctoption factor, or counters inhibitor
Binds to promoter region
Transcription occurs eg.g RNA polymerase binds, mRNA is produced
*Protein synthesis organelle structure
Ribosome has larger and smaller subunit: ribosomal protein and rNA.
*GMO injecting into vein rather than artery
Larger lumen so easier to put into blood
Less muscle/thinner wall so wasier to penetrate
Bloodpressure is less so less damage to vein - less blood loss
Vein is easier to find: nearer skin surface
Mitosis
PMAT - prophase, metaphase, anaphase, telophase
NOT cytokinesis or interphase
Produces two nuclei
Genetically identical to the orginal
Motor neurone infection by virus can stop nerve impulse transmission and lead to muscle paralysis
Motor neurone (its cell body, nucleus) is destroyed
Depolarisation does not occur in neurone, insuffiecient so no action potential set up in the neurone
Depolarisation/action potential does not occur in the neurone: Na+ does not diffuse into neurone
Neutotansmitter not released ar junction with muscle (at motor newurone preseynaptic emebrane/ motor end plate)
Lack of neurotransmitter release: vesicales contain NT do not move or fuse with presymaptic memebrane
Ca++ not released into muscle cytoplasm
Ca++ not released from sarcoplasmic reticulum/sactoplasm
no Ca++ to activate troponin
Muscle does not contract
*Provirus genetic structure and HeLa genetic structure similarities
Both contain bases Contain phosphate groups Have a pentose sugar Have phosphodiester bonds Discrete stands
*Human genome map
all the DNA found in a huamn/ the huamn species (all bases, introns, and exons)
Genes on different chromosomes/ different loci on same chromosome)
*Tumor suppressor gene
Could stop a potential tumour forming
Product stops/ regulates progression of cell cycle towards mitosis - keeps it in interphaae
Act as an inhibitor of transcription protien synthesis
DNA repair
Leads to apoptosis (shortens telomeres)
Specific DNA sequence from a blood cell codes for what that allows it to be susceptible to HIV?
proteiun/glycoprtein, this being CD4, found on cell surface membrane, that acts as a recpetor for HIV
What is the rod cell pigment, , made of?
opsin and retinal
Light stimulates a rod cell and what pigment changes?
rhodopsin
Once the pigment has changed, the concentration of sodium ions inside the rod cell …?
Once the pigment has changed, the concentration of sodium ions inside the rod cell DECREASES
After changing, the pigment takes time to become functional again. Why?
Because it has to bleach.
The cell that links a rod cell to a sensory neurone is a … neurone,
The cell that links a rod cell to a sensory neurone is a bipolar neurone,
Decrease in light leads to pupil dilation
Muscles work antagonistically
Circular muscle relaxes
Radial muscle contracts
CT vs/ mRI for studying brain structures
CT can only identify larger structures, MRI can identify smaller structures
Both identify soft tissue: MRI is better for soft tissue, CT for bones/tissues of different density, both for tumours
MRI uses radio waves/magnetic field, CT uses X-rays
Both give 2d/3d images - easier to get 3D from MRI
MRI IS NOISY, NEED TO KEEP STILL, NOT SO GOOD FOR PEOPLE WITH METAL IMPLANTS, PACEMAKERS
CT USES X-RAYS SO THERE ARE SAFETY ISSUES
Both images are only at one point in time]
MRI is more expensive than CT.
fMRI better than CT for studying brain function
View brain directly
Seeing brain activity over a period of time
Safer as does not used X-rays
No need to use special dyes.
Tumour appeared white in the MRI scans
Tumour tissue differs from brain tissue
Effect on scan : energy source - magnetic field/ radio waves - absorbed
Difference in blood supply -oxygen presence
Using info. diagrams - effect on the treatment on the tumour: a large circle, becoming a smaller cirlce
Treatment has been partially sucessful
Tumour reduced
In contact with less brain tissue, affecting less brain tissue, halved in size
(fMRI)
Functional magnetic resonance imaging or functional MRI
Two brain functions that would improve after treating a tumour at the front of the brain.
Two appropriate functions given, e.g. think, learn, show emotions, memory, personality, reasoning
Because tumour is situated in the frontal lobe/ cerebrum
Functions of enzymes in a metabolic process
Enzyme 1 converts subrate p to product q
This product becomes the substrate of the next step
Specificity
Controls the conversion
Speeds up the conversion
By reducing activation energy
Whole process can be controlled by end product inhibition
Suggest one NT that might bind to receptors on cell surface membrane in cardiac muscle cell in SAN
Acetylcholine or noradrelaine
Eye-like feature protruding from axon in sensory neurone.
Cell body
The simplest line in neurones that runs through the myelin sheaths
Axon
Describe the relationship
Between concentration of eugenic and % inhibition Na+ movement
Increasing Eugenol concentration increases percentage inhibition
Positive correlation
Non-linear correlation
Eugenol affects Ca2+ movement and reduces pain
Reduced Ca2+ enters presynaptic membrane into sensory neurone
Due to Ca2+ channel not opening - decreased sensitivity to Ca2+
Fewer vesicles move towards and fuse with presynaptic membrane.
Less neurotransmitter released into/less diffuses across synaptic gap.
Less neurotransmitter binds to receptors on post-synaptic membrane/adjacent neurone
Reduced depolarisation/ less Na+ or cation channels open
Threshold intensity/action potential, less likely to occur
Pain not being sensed as impulse stopped before entering CNS /leaving the sensory neurone.
IAA experiment control?
Cut shoot without IAA present/without agar blocks
How did Auxin affect growth of shoot?
Both sides of shoot taller
Than control
Both IAAs diffuse down, out of agar, to zone of elongation
Cell elongation occurs
Shoot beds to the right - bends away from side with (artificial) IAA
Due to more growth on left side of shoot/side with artificial IAA
*IAA is known to bind to transcription factors. How can IAA stimulate cells to synthesise protein?
IAA enters the cell.
Movement within cell/IAA in cytoplasm to nucleus
Effect when binds to transcription factor e.g. forms a transcription initiation complex or countering an inhibitor, joins to promotor region, activates transition factor
Switching on gene
Activity at promoter region, RNA polymerase activity
Allows formation of mRNA
Translation produces protein
Cellulose vs. Starch
Alpha glucose in starch and beta glucose in cellulose
Only starch/amylopectin can be branched, while cellulose is only a linear molecule
Starch contains two types of molecules, cellulose only one
Alternate monomers rotated through 180’ in cellulose only.
Only amylopectin/starch can have 1-6 glycosidic bonds, while cellulose has 1,4 glycosidic bonds only
Rank air tunnels of naked mole rats adapted
It would leave us gasping for air
This air has higher CO2 content
CO2 level in blood increases/pH of blood falls
Change detected by chemoreceptors in carotid body/artery/aortic body/aorta/medulla
Sends more impulses along neurones
To intercostal muscles/diaphragm
Causing an increased ventilation rate, rate of breathing, depth of breathing
Non-motile sperm structure
Irregularity of flagellum
Irregularity associated with mid region - mitochondria non-functional, less effective, not enough mitochondria
Importance of dispersion of colonies
Reduces inbreeding depression Increases outbreeding Leading to increase in genetic diversity Colony size regulation Increase in fecundity/fertility Increased chance of survival
The maximum change in pd across the membrane of this neurone during depolarisation
100mv
-70 to +30
Stage when the concentration of positive ions is greatest inside the axon
At +30, peak of graph, Na+ diffuse in, voltage-gated Na+ open
Stage when hyper polarisation first occurs
Curve goes down to -80
K+ leaves
Stage showing resting potential
First stage, before peak, at -70mv
After NT (ACh) release
NT diffuses across gap and binds to receptors on post-synaptic membrane
Gated channels open.
Na+ travels through post-synaptic membrane.
This causes a depolarisation
If sufficient present, an action potential is set up in post synoptic membrane/adjacent cell
Temporal or spatial summation occurs
This allows coordination one way flow of information,
It allows integration in post-synaptic cell.
NT is broken down by enzyme.
So that you do not get prolonged action potential in post synaptic membrane and to make receptors available again.
The fate of the products of NT break down: reabsorbed through presynaptic membrane.