Midterm 3- Split pea Flashcards
Sensory response pathway of plants
1)Sensory cells perceive a stimulus and transduces the information to an internal signal
2)Cell-Cell Signal released by the sensory cells travels throughout the body
3)Target cells receive the signal and change activity in a way that produces an appropriate response.
Receptor proteins
Detect environmental signals and change shape transferring the signal into an internal signal usually with a hormone
Signal Molecules
Located within the cell and elicit a response when bound to a matching receptor
Two methods of signal transduction
1)Phosphorlaytion, change of ADP into ATP on an associated protein
2)Secondary messengers: Trigger production of release of inter cellular signals that amplify a signal
Different type of response to signals
1)Activate membrane transport
2)Change in electrical potential or Ph
3)Change in gene expression
Phototropisim
Directed movement of plants in response to blue light
Why do plants bend towards blue light?
Blue light triggers the opening of stoma allowing for photosynthesis to occur
Photoreceptors
Receptors that detect blue light and intitate the phototropic response
Coleoptile
Protective sheath that is found on the tip of the plant that promotes the movement of plants towards light
Fritz Went experiment
Use of Mica (horomone blocking) and Agar(Hormone tranducting) in between coleptile and plant, the agar would allow movement to occur where as the mica did not
Auxin
Hormone that signals for plant elongation on the side opposite to detected light, promotes fruit development, leaf and fruit falling, differentiate xylem and phloem as well as vascular cambium, and simulates root growth
Auxin receptors
1)ABP1=Extracellular response
2)T1R1=Intracellular response
Acid growth hypothesis
1)Auxin triggers H+ pumps lowering the Ph to 4.5
2)Lowered Ph triggers expanisins to cut H bonds between cellulose and other cell wall polymers loosening the cell wall
3)K+ wants to restore chemical gradient so moves into the cell and brings water with it, expanding the cell
Role of Red light and Far red light in plants
Red light acts as an on switch for germination and far red light acts as an off switch for germination
Phytochrome and their conformations
Absorbs both red and far red light
Pr: Has absorbed FR light and needs red light, no germination occurs
PFR: Has absored Red light and needs FR light to change back, germination occurs
Etiolation
When no blue light is present then the plant grows extremly long, narrow, thin, and pale to try and break to the light
De-etoliation
Once light levels are sufficient stem growth slows and now energy is invested in chloroplast and leaves
Photoperiodism
Plants internal clock that is controlled by the CO gene, in short day plants they only flower during short days and long day plants only flower in long days
Effect of red and far red on photoperiodism
Red light triggers a daylight response and far red light triggers a night response
Florigen
Flowering horomone
Flowering Locus
Gene that promotes flowering when activated, it triggers the apical meristem to activate and form a flower.
Heliotropism
Tendency for certain plants to track the movement of the sun throughout the day and then reset over the course of the night
Heliotropisim and plant development
1)Tethered stems that cannot response to light photosynthesis less
2)As plant growth slows so did sunlight tracking
3)Auxin is expressed alternating amounts due to gene expression
Gravitropisim
Movement of roots downward in response to gravity
Statolith hypothesis
Hypothesis that states that the movement of roots downward is due to amyloplasts filled with starch, the startch grannuales are heavy and move to the tip of the roots activating pressure receptors
Gravitropisim and Auxin
1)Auxin flows normally untill the root is tipped to one side
2)Gravity sensing cells redistribuste the auxin towards the bottom of the root
3)Change in auxin levels trigger growth on the top side and slow the growth on the bottom side leading to a downward bending of the root
Root vs shoot response of auxin
In shoots the auxin causes the plant to bend towards the light, in the shoot it cause the plant to bend away from gravity
Wind response of plants
Plants produce shorter and stiffer stems in response to proteins produced when wind is detected by the plant
Thigmotropism
Movement in response to touch, tendrils will contact and object and grow towards it (pos) or roots will contact and object and move away from it (neg)
Thigmotropism and Venus fly trap triggering
1) At rest
2)Depolarization from opening of Ca2+ channels
3)Activation of K+ channels to slow depolarization
4)Peak depolarization dominated by K+
5)Initial re polarization due to K+ now moving out of the cell
6)Final repolarization and hyper polarization
7)Further hyper polarization to prevent consecutive firing
Diffrence in plant vs animal action potentials
Plants: Ca2+ and K+ signals, -120mv resting potential, H+ repolarization, slow speed and long cool down
Animal:Na+ and K+ signal, -70mv resting potential, Na+ and K+ repolarization, high speed and fast cool down
Cytokinens
Made in the root meristem and move up the plant, regulate growth by binding receptors that modify the cell cycle
Cell cycle phases
G1 GAP1
S Synthesis
G2 GAP2
M Mitosis
CDC25
Triggers mitosis from the G2 phase via dephosphorlation by CDK
CYCD3
Triggers G1->Sphase via phosphorlation with CDK
ABA
Inhibits growth and seed germination when conditions are unoptimal
Gibberellions
Simulate plant growth and are involved incoverting the endosperm of seeds into sugar
Requirements to trigger plant germination
1)H20
2)O2
3)Warm temperature
4)Damage or tampering of the seed coat
5)Small seeds will need red light
Process of germination triggered by gibberllions
1)Seed absorbs water
2)Gibberellons diffuse to the aleurone layer
3)Amylase is released and breaks down endosperm
4)Sugar is made available for growth
ABA stoma closing
1)ABA reaches gaurd cells inhibiting H+ ATPases
2)Cl- channels open and anions leave
3)K+ follows
4)Water leaves the cell and the guard cells are flaccid and stomata closing
Blue light stoma opening
1)Blue light stimulates photoreceptors allowing H+ to move out fo the cell
2)Cl- and K+ move into cell with water
3)Swollen guard cells
Brassinosteroids
Regulate the growth and plant body size, control cell division and root and shoot growth.
Brassinosteroid receptors
BRI1-Outer plant receptor
BRL- promotes phosphorylation inside of the cell
Ethylene
A gas hormone Involved in fruit ripening, leaf abscission and flower senescence. It converts starch into sugar, breaks down cell walls and chlorophyll
Cellulose microfibrils
Fibres inside of the stomata preventing it from expanding forcing it into the bean shape that is associated with stomata opening.
Four types of Mechanical defence
1)Bark
2)Waxy cuticle
3)Spikes,prickles, and thorns
4)Trichomes
Difference between spines, prickles, and thorns
Spines are modified leaves, Thorns are modified stems to prevent large herbivores, and prickles are modified epidermis that prevents smaller animals from predating on them
Gladular Trichome
Elongated shape that secret compounds like resin or formic acid and histones
Non gladular trichomes
Short and stiff trichomes that can be used to slow down insect movement and prevent proboscis insertion into the plant
Gorgons dewstick adaptation
Has trichomes that secret a sticky resin to attract and trap insects
Peppermint adaptation and Human use
Methol and Menthone repel bugs, humans use it for flavor
Lemon adaptation and Human use
Citrol slows down insect respiration and inhibits their movements and reaction time, humans use it for flavor and as insect repellent
Pine tree adaptation and Human use
Pinene repels insects, humans use it as a solvent and feul
Tanins and Human use
Derived from chloroplasts and inhibits herbivores digestion by binding to digestive proteins. Humans use it as a dye, leather tanning, preserving iron etc.
Pyrethroid and Human use
Found in crysanthmums, prevents the closing of sodium channels in insects, humans use it to treat parasites, pesticide, and mosquito control
Opium, caffeine, nicotine and Human use
Caffine->Nervous system protein disruption
Opium and Nicotine->Blocks firing of action potentials
Humans: Stimulants and pain killers
Stinging nettles adaptation
Injection of formic acid and histones using trichomes that act as hypodermic needles
Inducible plant defences
Defences that only activate when a threat is present
Constituent plant defences
Plant defences that are always being produced by the plant
3 adaptation types for plants vs insects
1)Antixenosis- Disrupts insect behaviour
2)Tolerance- Insects are capable of tolerating toxin
3)Antibiosis- Affects the physiology of the insect
Ways insects use plants
1)Herbivory- directly eaten
2)Phloem feeding- drink the sugar water
3)Egglaying
Hypersensitive response
Response induced in plants when pathogens are present
1)Stomata close
2)Toxins are produced
3)sugars are moved into the cytosol
4)Cell walls thicken to restrict movement
5)Cells infected rapidly die
Systemic acquired resistence
PR gene signals to produce hormones that warn the rest of the plant of infection, they also attack cell walls of pathogens, and stimulate the strengthening of cell walls.
Protease inhibitor
Type of molecule that block the digestive proteases of predators that disrupt that herbivores ability to digest the plant
Systemin
Signals for undamaged cells to prepare for predator
1)Systemin is released from damaged cells
2)Hormone travels via the phloem to the membrane receptors
3)Triggers production of Jasmonic acid
4)Activates transcription of protease inhibitors
Volatile compounds
Compounds release into the air that warn other plants of herbivoires
Pheromone defense
Plants produce pheromones to signal for other species that eat it’s predetors
Positive feedback of climate change
1)Warmer climates more fires,more co2
2)melting icecaps, less solar reflection
3)Tundra melting releasing co2
Negative feedback of climate change
Plants like co2 so more plants will grow
4 outcomes of heat on a plant
1)Energy is absorbed
2)Heat dissipation
3)Convection heat loss
4)Evaporation cooling
Bowen ratio
Heat loss via convection/ heat loss via evaporation, when water is sufficient Bowen ration is low
C3 plant
Traps both CO2 and O2 in the spongy mesophyl meaning the two compete for the binding site of rubsico
C4 plants
Spatial separation of CO2 and O2 inside of the plant allowing more CO2 to bind to RUBISCO
CAM plants
Temporal separation of CO2 and O2, CO2 is collected at night and then processed during the day
CAM idling
permits survival under extreme water loss where somata close during both the day and night time
Affect of climate change and range shifts
Range shifts occur due to warmer climates allowing species to move further north
Affect of photoperiodism and climate change
Warmer temperature favours flowers to bloom earlier and earlier to get a head start on the year
Mechanoreceptors
Responsible to changes in pressure and are involved in orientation of the body and hearing
Describe the process of hearing
Pressure waves in the air his the tympanic membrane and travel to the ear drum to which is transmits the signal to the middle ear bones to the stapes and then the oval window which vibrates the fluid in the cochlea that is sensed by the hairs in the ears
Choclea
set of internal membranes divided into three chambers that house the basilor and tectorial membrane
Basilar membrane
Long membrane that goes thick to thin and transfers it’s vibration to the tectorial membrane
Stereocillia
Hairs arranged from smallest to largest, They serve as the key mechanosensors, responding to fluid motion for various functions, including hearing and balance.
Kinnocillium
Tallest piece of the ear cells and are linked via mechanoreceptor channels that will open when stretched
Process of activating the kinnocillium
1)Pressure wave moves towards the stereocillia
2)Potassium channels flow with calcium into the cell
3)Calcium triggers the synaptic vesicles to fuse with the plasma membrane
4)Neurotransmitter is released into the afferent neruon
What causes hearing loss
1)Tiplink breakage
2)Damage to the sterocillia
3)Ribbon synapse damage
4)Damage to the hair cells
Cornea
Refracts light to the back of the eye
Lens
Focuses the light to the correct distance of the eye
Retina
a layer of photoreceptors cells and glial cells within the eye that captures incoming photons and transmits them along neuronal pathways as both electrical and chemical signals for the brain to perceive a visual picture.
Fovea
a small depression within the neurosensory retina where visual acuity is the highest
Three portions of the vertebrate eye
1)Photoreceptors respond to light held in place via epithelial cells
2)Bipolar cells transmit signal to ganglion cells
3)Ganglion cells, send the message to the brain via the optic nerve
Rods
Sensitive to dim light but not colour
Cones
Less sensitive to faint light but are stimulated by different wavelengths allowing for colour vision
Describe how a photon of light activates the eyes
1)Rhodopsin is activated when light causes retinal to switch cis to trans
2)Rhodopsin activates Transducin which in turn activates PDE
3)PDE breaks down cGMP into GMP
4)as cGMP concentration decreases cGMP gated sodium channels in the plasma membrane of the the photoreceptors closes
5)Hyper polarization occurs
6)Decrease in neurotransmitters release from photo receptor to bipolar cells
7)New pattern of action potential is sent via ganglion cells
G protein amplification of sight
1)Rhodopsin activates 800 g-protein
2)Each g protein activates PDE
3)Each PDE catalyzes 6cGMP
Cones and their wavelengths
Red-Long wavelength
green-Medium wavelengths
blue-short wavelength
Signalling in the olfactory glands
1)Odarant binds to odor receptor
2)g protien activates splitting into alpah and beta subunits
3)alpha subunit goes to adenyly cyclase3 and ATP is used to produce CAMP
4)cAMP activates the sodium gated and calcium gated channels leading to depolarization
5)Calcium binds to chloride channels
6)Action potential is fired
Photo reception vs Olfaction
Olfaction:100s of proteins, receptor neurons, gprotien,depolarization,cAMP
Photoreception:3 proteins,epithelial, g protein, hyper polarization, cGMP
Glucose sensing in the body
1)Glucose increases ATP
2)ATP causes closure of the K channels
3)Depolarization
4)Activation of the Ca2+ channels
5)Calcium triggers release of insulin
Ficks law
Diffusion of gas dependant on
1)Solubility of gas
2)Temperature
3)Surface area for diffusion
4)Difference in partial pressure
5)Barrier thickness
Partial pressure
Pressure of a particular gas in a mixture of gas causing the diffusion of gas from high to low pressure
5 components of circulation
1)Ventilation
2)Diffusion
3)Circulation
4)Diffusion
5)Respiration
Pleural cavity
thin layer of cells in between the lungs and chest cavity to keep the lungs inflated
Negative pressure
Used to pull air into the lungs in inhalation vka the increase in area of the lungs
Positive pressure
Used to push air out of the body with the diaphragm rising up and shrinking the chest cavity
CO2 and water reaction
CO2+H2O<->H2CO2<->H+ + HCO3-
Left shift in oxygen binding
Increases O2 affinity, speeds up loading of o2 but slows down o2 unloading, low temp, higher pH
Right shift in oxygen binding
Decreases O2 affinity, decreases oxygen loading in the lung but increases unloading in the tissues, low pH and high temp
Carbonic anhydrase
Catalyses the formation of carbonic acid from CO2 and H2O
Arteries
Tough, thick walled vessels that take blood away from the heart under high pressure
Capillaries
Thinnest blood vessels allowing exchange of gas and minerals with the tissues
Veins
thin walled vessels that shuttle returning blood to the heart
Aorta
Large artery that receives blood from the heat and shuttles it to the arteries
Pulmonary circuit
the system of transportation that shunts de-oxygenated blood from the heart to the lungs to be re-saturated with oxygen before being dispersed into the systemic circulation.
Systemic circuit
carries oxygenated blood from the left ventricle, through the arteries, to the capillaries in the tissues of the body
Lymphatic system
System that runs alongside the circulatory system to collect excess fluid and return it to the primary circuit
Blood flow through the heart
Blood comes into the right atrium from the body, moves into the right ventricle and is pushed into the pulmonary arteries in the lungs. After picking up oxygen, the blood travels back to the heart through the pulmonary veins into the left atrium, to the left ventricle and out to the body’s tissues through the aorta.
Pulmonary circuit path
Right atria->right ventricle->Lungs
Systemic circuit path
Lungs->left atrium->left ventricle->Aorta->Systemic circuit
Right atrioventicular valve
prevents blood backflow from the right ventricle to the right atrium
Pulmonary valve
It’s between the lower right heart chamber (right ventricle) and the artery that delivers blood to the lungs (pulmonary artery)
Left atrioventricular valve
allow blood to flow from your left atrium to your left ventricle. And they prevent backward flow from the left ventricle to the left atrium
Aortic valve
keeps blood flowing from your heart’s lower left chamber (left ventricle) to the aorta which is the main artery bringing blood from the heart to the body.
Specialty of the cardiac tissue
1)Gap junctions between cells allowing for electrical continuity
2)Desmosomes to link cells allowing for the same force to be applied
Process of cardiac signalling with ions
1)Na channels close
2)Ca2+ channels open allowing for plateau
3)Ca2+ closes
4)Re polarization occurs
Funny current
Immediate rebound of the heartbeat signal due to opening of sodium channels
Pace maker cells
Cells found in the sinoatrial node that control the heartbeat
Signal of a heartbeat
1)SA node generates electrical signal
2)Signal from SA node propagating to atria leading to blood being ejected
3)signal is sent to AV node for the ventricles
4)Impulse is send down the bundle of HIS and Purjinke fibers up and down the bottom of the heart
5)Ventricle relaxes
Systole phase
Contraction phase of atria
Dystole phase
Relaxed phase of the heart
Baroreceptors
Detects changes in blood pressure that will trigger signals to the heart to control the rate and force of contraction
Three types of nitrogenous waste
Uric acid:Low water, high energy, birds and reptiles
Urea:Medium water and energy usage, mammals and amphibians
Amonia: requires excess water to flush, toxic, little energy, bony fish use
Functions of the Kidneys
1)Electrolyte balance
2)Nitrogenous waste removal
3)pH of blood
4)Blood pressure
5)Hormone production
6)Calcium and potassium homeostasis
7)regulate RBC production
Cortical nephron
Shorter nephron that does not dip into the medula
Juxatamedullary nephron
Longer nephron, dips into the medula
Route of waste water
Glomerulus->Proximal tubule->Loop of Henly->Distal tubule->collecting duct
Glomerulus
Removes small molecules and large volumes of water using pressure filtration system
GFR filtration rate
1)Myogenic response
2)Tubleglomerular feedback
3)Mesangial control
Myogenic response
Stretch recpetros respond to an increase in pressure contracting the muscle to increase pressure or relax it to decrease pressure
Tubularglomeular feedback
Macula densa regulates the diameter of the bowmans capsule
Mesangial control
Alters the permiability of the bowmans capsle
Proximal tubule
Filters out urea,glucose,amino acids, vitamins,electrolytes via microvilli
Process of absorption in proximal tubule
1)Na+/K+ ATPase in the basolateral membrane removes NA+ in the fluid
2)Na+ is used to co transport other ions
3)Solutes move into the cell then into the blood stream
4)Water follows the ions
Loop of Henle
Descending limb removes water, thin ascending limb removes cl- and na+ passively and the thick ascending limb removes Cl- and Na+ actively
Distal Tubule
Regulated via osmotic stress and can help reabsorb more water if necessary
Collecting duct
Able to withdraw more ions with proper horomones, leads the filtered material out of the kidney
Aldosterone
Activates sodium pumps in distal tubule
Antideuretic hormone
Activates the insertion of aquaporins into the apical membrane of the collecting duct and increases its permeability to UREA
