Glucose Lab
Define glycemic load. Give an example of a food type with a high glycemic load and a low glycemic load
Definition: the amount and duration of glucose elevation in the blood. High: foods with high sugar/starch content. Low: protein/fat/fibrous foods
Define antigen and antibody.
Antigen: Substances that trigger an immune response from the body. Triggers the production of antibodies leading to foreign invader destruction.
Antibody: Binds to antigen to create a target for the immune system
Define permeability and conductance. What do they both rely on?
Permeability: how much an ion can cross a cell membrane
Conductance: how much charge can be conducted across the membrane from an ion
Both rely on how many ion channels are open.
Define temporal summation and spatial summation
Temporal Summation: When multiple excitatory signals arrive at a synapse closely in time, cumulatively increasing the membrane potential. If the combined effect is sufficient to cross the threshold, it triggers an action potential in the neuron.
Spatial Summation: When multiple excitatory signals from many synapses arrive at a synapse simultaneously. If the combined effect is sufficient to cross the threshold, it triggers an action potential in the neuron.
What is a blind spot?
The lack of light-sensitive cells causes a blind spot, due to them entering the optic nerve
light-sensitive cells: Rod cells are susceptible to light and function in night vision, whereas cone cells can detect a wide spectrum of light photons and are responsible for color vision.
For both insulin and glucagon, describe the steps by which they trigger a change in blood glucose level. Start at "released from pancreas", and end at "blood glucose drops/increases"
Insulin: pancreas > bloodstream > activates glucose transporters in cells > blood glucose drops
Glucagon: pancreas > bloodstream > stimulates liver cells to break glycogen down into glucose > blood glucose increases
What is the normal range of clotting time for human blood?
Does a blood clotting time of 6 minutes and 30 seconds be the norm?
A) 2-6 minutes
B) No
If you increase the internal Na+ concentration, what happens to the following: K+ concentration, Na+ concentration gradient, Na+ equilibrium potential, resting membrane potential.
K+ concentration: no change
Na+ concentration gradient: decreases
Na+ equilibrium potential: decreases (moves towards 0)
Resting membrane potential: decreases (becomes more negative)
Explain in simple language, in a way anyone could understand, how you determined the conduction velocity of the nerve
(Time it took to get from 1 probe to another probe) / Distance
Define and use the following terms: receptive field, sensory adaptation, myopia, hyperopia, astigmatism, accommodation (of the lens), optic nerve, optic disc, presbyopia, conduction deafness, sensorineural deafness, presbycusis
receptive field: the sensory space that can evoke a sensory neuronal response
sensory adaptation: the change in response to stimuli- tend to ignore sounds in the background
myopia: also known as near-sightedness, is an eye disease where light from distant objects focuses in front of, instead of on, the retina
hyperopia: light focuses behind the retina
astigmatism: lack of roundness of the eyeball
accommodation:changes optical power to maintain a clear image or focus on an object as its distance varies
optic nerve: nerve at the back of the eyeball that carries sensory stimuli to the brain
conduction deafness: hearing loss caused by physical obstruction
sensorineural deafness: hearing loss caused by nerve defect
presbycusis: hearing loss with age
If you haven't eaten a meal in a long time, what will happen to your insulin, glucagon, and glucose levels?
Insulin down, glucagon up, glucose up
Provide the function of the following:
1) thrombocyte
2) lymphocyte
3) erythrocyte
1) coagulate at damaged blood vessels
2) responds to specific pathogens and creates memory cells to prevent a successful secondary infection
3) delivers oxygen to cells with a protein that binds oxygen
If you decrease the external K+ concentration, what happens to the following: K+ concentration gradient, resting membrane potential, initiation of action potential, rising phase of action potential, falling phase of action potential.
K+ concentration gradient: increases
Resting membrane potential: decreases
Initiation of action potential: takes longer
Rising phase of action potential: no change/slightly speeds up possibly
Falling phase of action potential: goes faster
Describe and explain physiologically the effect of temperature on conduction velocity
At higher temperatures, the speed of conduction increases due to the increased mobility of ions across the cell membrane. This is because higher temperatures increase the kinetic energy of ions, allowing them to move more rapidly across the cell membrane, resulting in a faster conduction velocity. However, if temperatures exceed a certain point, the speed of conduction can decrease as the protein structures in the cell membrane denature, affecting the ion channels. This can result in decreased conduction velocity, as well as potential damage to the nerve or muscle fibers.
The reduction in temperature can cause the channels to close or become less responsive, leading to a decrease in the overall speed of the nerve impulse. Ion channels open and close slower, and ions move slower as well.
What is the type of graph to plot allometric equations?
Log-log transformation places numbers into a geometric domain so that proportional deviations are represented consistently, independent of the scale and units of measurement.
You’ve just finished your crayfish experiment and written down the following data: Concentration of glucose standard: 0.5 mg/dL. Absorbance of standard: 12. Absorbance of unknown glucose sample: 8. What is the concentration of your unknown glucose sample?
0.5/12 = x/8
0.33 mg/dL
I am a type A+. My friend is type B-. Which blood types can we donate to and receive from?
Me: Type A+ can donate to A+ and AB+, and receive from A+, A-, O+, and O-
Friend: Type B- can donate to B+, B-, AB+, and AB-, and receive from B- and O-
Calculate the membrane potential for a cell with the following concentrations:
pK = 1.5, pNa = 0.75
K(out) = 50, K(in) = 300
Na(out) = 450, Na(in) = 75
58log[ (1.5*50 + 0.75*450) / (1.5*300 + 0.75*75) ]
58log[(75+337.5)/(450+56.25)]
58log[0.815]
-5.162 mV
Explain why the refractory period exists (what causes it), and what evidence you have from this experiment that it exists:
The refractory period is caused by the inactivation of sodium channels that occurs after an action potential is fired. During an action potential, sodium channels open, allowing positively charged sodium ions to rush into the neuron and depolarize the membrane. Once the membrane potential reaches a certain threshold, the neuron fires an action potential. However, after the action potential has been fired, the sodium channels become inactive, and it takes time for them to recover and be ready to fire again.
From this lab, we saw that an action potential did not occur immediately after an action potential occurred, this is because the neuron was going through the refractory period.
If a 20 gram snake starts at 30 degrees Celsius, how long would it take for it to cool to 25 degrees? Assume the cooling rate is equal to 2.5(mass)^(-0.67).
Y= 2.5 (20)^ (-0.67)
Y=0.335 deg/min
5 degrees/0.335 = 15 minutes
Compare and contrast the physiology of glucose control in crustaceans and vertebrates.
In vertebrates, blood glucose is controlled by pancreatic hormones insulin and glucagon. In crustaceans, glucose is controlled by crustacean hyperglycemic and hypoglycemic hormones, produce in the X-organs in the eyestalk
You centrifuge a capillary tube of your blood. You measure the entire liquid to take up 16mm, and the red liquid at the bottom takes up 7.2mm. What is your hematocrit?
7.2/16 = 0.45 or 45%
If you decrease the permeability of sodium channels, what is the effect on the resting membrane potential, initiation of action potential, rising phase of action potential, and falling phase of action potential.
Resting membrane potential: no change
Initiation of action potential: slower
Rising phase of action potential: slower
Falling phase of action potential: no change
Describe and explain physiologically the relationship between stimulus strength and stimulus duration in producing an action potential
Stimulus strength refers to the intensity of a stimulus, which can be measured by the magnitude of the depolarization it causes in the neuron's membrane potential. When a stimulus is applied to a neuron, it causes the opening of ion channels in the membrane, allowing ions such as sodium (Na+) and calcium (Ca2+) to flow into the cell, depolarizing the membrane potential. The stronger the stimulus, the more ion channels will open, allowing more ions to flow in, and producing a greater depolarization of the membrane potential. If the depolarization exceeds the threshold for firing an action potential, then an action potential will be generated.
Stimulus duration, on the other hand, refers to how long the stimulus is applied to the neuron. If a stimulus is applied for a short duration, it may not be enough to depolarize the neuron's membrane potential to the threshold required for firing an action potential. However, if the stimulus is applied for a longer duration, it may allow enough time for the depolarization to build up and reach the threshold for firing an action potential.
What is the the image in complementary colors that appear after continuous exposure to a color in one visual field area?
An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image.
Afterimages occur because photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus