PHYL Final

to allow signal to spread quick to neighbouring cells so all cells behave the same way at the same time, smooth muscle cells are connected by_______.

Gap Junction

Potassium chloride (KCl) is a salt made of two ions, K+ and Cl-. The opposing electrical charge of K+ and Cl- is the force that keeps KCl together. Based on this information, which types of chemical bonds are present in KCl?

ionic bonds

Exocrine cells in the pancreas produce digestive enzymes (i.e proteins). Which organelle would you expect to find in large numbers within these cells?

rough endoplasmic reticulum

In addition to our lungs and skin that can remove waste (CO2, volatile acids, head) from our body, which of these physiological systems are the main "waste disposal systems" in our bodies?

renal and digestive systems

When you sweat, water in your cells moves into your blood and then onto your skin. Which of the following sequences best describe this movement?

Intracellular fluid --> extracellular fluid --> external environment

When a tissue is injured, a chemical is released that activate platelets to start the blood clotting process. Once these platelets are activated, they release another chemical that stimulate the activation of more platelets. This is an example of _____________.

positive feedback loop

Which of the following statement best describes the ability of the body to maintain homeostasis?

Quickly restoring changing conditions to within a normal range

A teaspoon of olive oil is dropped into 1 L of water. Select ALL the characteristics that accurately describe olive oil in this situation.

hydrophobic, lipid, non-polar molecule

Solution A contains 100 mL of hydrochloric acid (HCl) in 1 L of water. Solution B contains 250 mL of hydrochloric acid (HCl) into 2 L of water. Which of the following statement is TRUE?

Solution B is more acidic than solution A

During a 5h-long movie marathon, you enjoyed the salty deliciousness of popcorn and chips (remember: salt is NaCl). What is the most appropriate response to restore homeostasis?

Excrete more Na+ from the kidneys

phopspholipid

lipid molecule with glycerol, 2 fatty acids and a phosphate group

non-essential amino acids

molecule that the human body can synthesize that contains an amino group (NH2) and a carboxyl group (COOH).

Ribolnucleic acid (RNA)

series of nucleotides linked with a sugar-phosphate backbone

disaccharide

2 molecules of carbohydrate linked together

saturated fatty acid

lipid molecule with carbons linked to hydrogen to their fullest capacity

You drop a normal red blood cell into a solution of unknown composition. The cell swells. Which of the following statements would be TRUE?

The concentration of non-penetrating solutes in the solution is less than 300 mOsm. The solution is hypotonic to the cell.Water moved into the cell.

What is the osmolarity of a solution that contains 100 mM of glucose, 20 mM of KCl, 10 mM of CaCl2, and 60 mM of urea?

230

Na+/K+ pump

It moves Na+ out of the cell and K+ into the cell

The transporter GLUT4 is a uniport that moves glucose passively across cell membrane. Given this information, which of the following statements is TRUE?

GLUT4 is a protein carrier

In the immune system, specialized cells transport large pathogens from the extracellular to the intracellular environment. Given your knowledge of cellular transport, how would large pathogens be transported inside the cell during an immune response?

via endocytosis

The concentration of sodium (Na+) in the intracellular fluid is ________ than in the interstitial fluid. Therefore, when Na+ leak channels are present, Na+ move towards the __________.

lower; intracellular fluid

There are 2 solutions separated by a semipermeable membrane. Only water can pass through. Solution A is 20 mM glucose and solution B is 15 mM NaCl. Which of the following statements is TRUE?

Water flows from A to B

A variable is proportional to the rate of diffusion if an increase in the variable will increase diffusion rate. If an increase in the variable will instead decrease diffusion rate, the variable is described as inversely proportional.

Fick's law of diffusion states that the rate of diffusion of a solute across a plasma membrane is:

proportional to concentration gradient, surface area and membrane permeability

The reaction CO2 + H2O

More CO2 is produced

A biomedical engineer student created a molecule that increases the activity of the enzyme glutamate dehydrogenase (GDH) in order to treat a specific case of hypoglycemia in infants. This molecule works by binding directly to the GDH enzyme, changing its shape, and allowing the ligand to bind to GDH. This molecule is a(n) __________.

Allosteric activator

Which of the following statements does NOT correctly explain why enzymes are essential to physiology?

Enzymes prevent the degradation of ATP.

Just after we eat a lipid-full meal (e.g. fish & chips), most fats we ate are stored in our fat tissue. This is done by glycerol and fatty acids joining together to synthesize triglycerides in an endergonic reaction. Which of the following statement is TRUE?

Energy gets stored during triglyceride synthesis.

Glycolysis

Glucose produces ATP

Glycogenesis

Glucose is stored as glycogen

De novo lipogenesis

Glucose is stored as triglycerides

Glycogenolysis

Glucose is released from glycogen

Gluconeogenesis

Glucose is produced from lactate or amino acids

Which of the following is NOT a difference between the aerobic and anaerobic metabolism of glucose?

Anaerobic metabolism produces more NADH than aerobic metabolism

The aerobic metabolism of one molecule of glucose yields a maximum of ________ net ATP.

32

Glycogen

Glycogenolysis

Pyruvate or lactate

Gluconeogenesis

Triglycerides

Lipolysis

Fatty acids

Beta-oxidation

.

Glucose

Glycolysis,

De novo lipogenesis

Acetyl-CoA

Citric acid cycle

Amino acid

Deamination

The Nernst equilibrium potential for ion A is -40 mV. The Nernst equilibrium potential for ion B is -10 mV. The resting membrane potential of this cell is -30 mV. Which of the following statement is TRUE?

The cell membrane is more permeable to ion A than to ion B.

The lymphatic system is involved in immunity and other physiological functions. Which of the following statements about the lymphatic system is TRUE?

The lymphatic system absorbs some fluid from the interstitial space and filters it before returning it to the blood circulation.

Innate immune system

Immune responses are the same for chickenpox and zika viruses.The low pH of the stomach is part of this immune system. Fever is part of this immune system

Acquired immune system

It prevents you from getting the chickenpox twice in your lifetime

Both innate and acquired immune systems

It works to protect the body from disease-causing pathogens

Which of the following characteristics correctly describe inflammation?

The site of the injury becomes red and warm. It is easier for white blood cells to leave the blood and enter the tissue. Pathogens undergo phagocytosis

Which of these lymphoid organs play a role in filtering pathogens?

Tonsils,Lymph nodes of the armpit, Lymph nodes of the groin, Spleen

Activation of helper T cells (CD4+ T cells) is essential for antigen recognition. Order the events below that follow the activation and proliferation of helper T cells due to a VIRAL infection.

Infected cells present antigen determinants on MHC I molecules.Helper T cells (CD4+) activate cytotoxic T cells (CD8+).Cytotoxic T cells proliferate. Granzymes and perforin are secreted. Infected cells die via apoptosis.

T cell receptor

Antigen determinant

CD4 protein

MHC II

CD28 protein

B7 protein

IL-1 receptor

IL-1

Where do you expect to find MHC II molecules?

On the cell surface of antigen-presenting cells

Last week, Courtney participated in the blood drive of her University. Knowing her blood type is B-, select all blood types Courtney can donate to.

B-, AB+,B+, AB

\-.

the events that would lead to an inhibitory potential

Increased potassium movement towards the extracellular fluid. More potassium channels open

"Permeability" is a key concept in physiology. How would you explain the phrase "decreased K+ permeability" to a person who does not have a science background?

Decreased K+ permeability means that it is more difficult for K+ to move across the plasma membrane.

A neuron that sends signals from the brain to the smooth muscle of your bladder can be characterized as ____________?

an efferent neuron, part of the autonomic nervous system, part of the peripheral nervous system

The disease "herpes" occurs when the herpes simplex virus moves very quickly from the cell body to the axon terminal of neurons. Based on this information, which type of transport does the herpes simplex virus use?

Axonal transport using the microtubule system

Draw a neuron, draw one Na+ channel and one K+ channel in the membrane of its trigger zone, and label the inside and outside of the cell with "low Na+ concentration", "high Na+ concentration", "low K+ concentration", and "high K+ concentration". Based on this information, which of these events would happen if K+ channels opened while Na+ channels remained closed?

K+ permeability would be increased.

Which of these signals will reach the axon terminal the fastest?

An action potential using saltatory conduction in a large axon

action potential

Last Friday afternoon, you studied material from PHYL while listening to quiet classical music. Then, later that same evening, you attended a rock concert at the Scotiabank Centre. What is the only way your auditory system can code the difference in loudness between the quiet and loud music?

The action potentials would have a higher frequency at the rock concert (e.g. 100 action potentials every second instead of 10).

You run an experiment where you place a neuron in a solution that replicates the extracellular fluid. You then stimulate the neuron at the trigger zone and record the changes in potential at the axon terminal. However, during a practice run, you notice that the membrane potential in the axon terminal never changed so no action potentials reached the axon terminal. You know the stimulus is above threshold, that myelin is present, and that voltage-gated Na+ and K+ channels are present and functioning.

Which of the following verifications would help you determine why your experiment is failing?

Checking the concentration of Na+ and K+ in the experimental solution

In response to neurotransmitter release at a synapse in the central nervous system, the postsynaptic neuron conducts and action potential to its axons terminal.

Which of these would you expect was the neurotransmitter?

Glutamate

Organize the following events in the order (1-5) in which they occur at a chemical synapse.

Action potentials reach the axon terminal.

Voltage-gated Ca2+ channels open in the plasma membrane of the axon terminal. Ca2+ enter the cell, via passive transport. Pre-synthesized neurotransmitters are released into the synaptic cleft via exocytosis. Neurotransmitter bind to receptors on the post-synaptic cell.

Which of the following would increase the amount of neurotransmitter released?

Temporal summation of EPSPs at the trigger zone

In the eye, photoreceptors called rods receive visual sensory input. Several rods will synapse with the same bipolar cell and then several bipolar cells synapse with the same ganglion cell. The ganglion cell transmits the information to the central nervous system.

signal convergence providing less precise information about a visual stimulus.

Acetylcholine (ACh) is a neurotransmitter that can bind to two types of receptors: nicotinic and muscarinic. The nicotinic receptor is a receptor-channel while the muscarinic receptor is a G-protein coupled receptor (GPCR).

Based on this information, which of the following statements is FALSE about the NICOTINIC receptor?

The nicotinic receptor requires intracellular second-messengers to work.

The postsynaptic neuron has a resting membrane potential of -70 mV and a threshold of -57 mV.

Fifteen neurons send signals to this postsynaptic neuron at the same time. Four of these neurons produce EPSPs of 2 mV each at the trigger zone. Seven neurons produce EPSPs of 1 mV each at the trigger zone. The other 4 neurons produce IPSPs of -3 mV each at the trigger zone.

Will an action potential be generated in the postsynaptic neuron?

no

Excitatory neurotransmitters of the CNS may act by opening _____________ channels.

Na+ and acetylcholine

You want to increase the response of the postsynaptic neuron to neurotransmitter secreted by the presynaptic neuron.

You pick a drug to use --- which of these actions would give the response you need?

Block enzymatic breakdown of the neurotransmitter in the synaptic cleft

Your heart rate is controlled by synapses between neurons and the heart. In these synapses, ACh binds to its muscarinic receptors and slows your heart rate down. Based on this information, how would you treat someone who has an abnormally low heart rate?

HINT: Determine whether you would want to increase or decrease the actions of ACh in this situation.

Treat with atropine, a competitive antagonist of ACh

Which of the following phase(s) of a skeletal muscle twitch do(es) NOT require ATP?

Latent period

In the sarcoplasm, calcium (Ca2+) ions act to ____________

Remove the blocking action of tropomyosin

Drug X inhibits acetylcholinesterase in the neuromuscular junction. Which effect would drug X have on the contraction of the muscle fiber?

Drug X would increase the duration and strength of muscle contraction.

Which of the following statements best describes excitation-contraction coupling (ECC)?

Action potentials in the myofiber are necessary for the shortening of sarcomeres.

Which of the following would NOT be a plausible explanation for muscular fatigue?

Decreased diameter of the myofiber

Only in muscles

A somatic motor neuron releases Ach via exocytosis.Depolarization in the target cell leads the conformational change of DHPR and RyR proteins.

The depolarization travels down the T-tubules of the target cell