If an aerobic organism is exposed to oxygen that contains a radioactive oxygen isotope, which of the molecules listed below is likely to be radio labeled
A. water is a correct answer be
b. pyruvate I choose this answer because
C. NADH and FADH2
D. CO2
Explain why the correct answer is correct and the other answers are wrong
Answer
- A. water
Explanation:
- Aerobic respiration involves three stages. The glycolysis in which glucose is converted to two pyruvate molecules, TCA cycle which forms electron carriers and ATP, and lastly, oxidative phosphorylation which has electron transport chain and chemiosmosis. Oxygen is important because it acts as the final electron acceptor. Electrons are passed from one molecule to another, and energy is released and in chemiosmosis, the energy stored in the gradient is used to make ATP. Oxygen sits at the end of ETC, picking up protons to form water. Thus, if oxygen is radiolabelled, we will see the label in water molecule.
- Pyruvate does not use oxygen; it is formed by splitting glucose molecule
- NADH and FADH are not formed with the use of oxygen, there they cannot contain the radiolabelled oxygen as well
- Carbon dioxide is produced by decarboxylation of molecules in TCA cycle, which means it is not formed by use of oxygen either.
What anterior arm muscle can you observe when you flex a heavy object?
Answer
- Flexor muscle
Explanation:
The muscles in the posterior compartment of the forearm are extensor muscles while the anterior muscles are the flexor muscles. When flexing the arm, the muscle on the anterior part that is visible is the flexor muscle. biceps is one type of flexor muscle that is visible when lifting a heavy object as they bulge upwards.
What anterior arm muscle can you observe when you flex a heavy object?
Answer
- Flexor muscle
Explanation:
The muscles in the posterior compartment of the forearm are extensor muscles while the anterior muscles are the flexor muscles. When flexing the arm, the muscle on the anterior part that is visible is the flexor muscle. biceps is one type of flexor muscle that is visible when lifting a heavy object as they bulge upwards.
Besides diffusion, cells can also move molecules using motor proteins. Many motor proteins move at about 10 micrometers/second. Given this information, how many hours will it take for a motor protein to transport another molecule a distance of 1 meter? (enter a number, rounded to the nearest hour)
Answer
- 28 hours to the nearest hour
Explanation:
The motor proteins speed is 10 micrometers/second.
This implies that for every 1 second, the motor proteins moves 10 micrometers
To move 1 meter, which is equivalent to 1,000,000 micrometers, motor proteins will spend how much time?
10 um = 1 second
1,000,000 um = ?
1,000,000 * 1 / 10 = 100,000 seconds
Convert to hours
3600 seconds = 1 hour
100,000 seconds = ?
100,000 * 1 / 3600 = 27.78 hours which is 28 hours to the nearest hour
In the fertilization process, what is process that prevents the second sperm from entering the ovum after the first sperm has inserted itself into the ovum?
a) the propagation of Ca+ wave that solidifies the ovum cell wall
b) the propagation of Na+ wave that solidifies the ovum cell wall
c) the propagation of K+ wave that solidifies the ovum cell wall
d) the ovum cell wall has become an egg shell
e) the second sperm can always enter the ovum independent of whether the first sperm had inserted itself into the ovum
Answer
- a) the propagation of Ca+ wave that solidifies the ovum cell wall
Explanation:
When the first sperm enters the oocyte, the oocyte deployes two mechanisms to prevent another sperm from fertilizing the same oocyte. The first mechanism is a change in sodium ion permeability upon binding of the first sperm which depolarizes the oocyte plasma membrane. An influx of calcium ions triggers the second mechanism through zonal inhibiting proteins.
The four broad categories of cells include those specialized for each of the following functions except A. movement. B. synthesis of complex molecules. C. secretion. D. support. E. conduction of electrical impulses.
Answer
- B. synthesis of complex molecules.
Explanation:
The four broad categories of cells include epithelial cells which are specialized for protection from injury and digestion within the gut through production of substances. Nerve cells are responsible in conducting electrical impulse. Muscle cells are responsible for movement and regulating other organs. Connective tissue cells offer structural strength to the body and defends against invaders.
the three ways that neurotransmitters can be removed from a synapse
Answer
-
- Diffusion
- Reuptake
- Degradation
Explanation:
-
- The neurotransmitter can drift away from the synaptic cleft where it can no longer have an effect on the receptor.
- The neurotransmitter can as well be degraded or deactivated by specific enzymes such a acetylcholinesterase.
- The neurotransmitter can also be taken back into the axon terminal from where it was released, most common with serotonin and dopamine.
Why is using a blank important when measuring with spectrophotometer?
Answer
- To ensure you document the influence of the cuvette itself on your readings.
Explanation:
Spectrophotometry can be used to theoretically measure any substance that absorbs light. It is important to make sure that the absorbance only reflects on the substances inside the cuvette and not any other property like cuvette itself. This can be determined by blanking, which measures the absorbance of an empty cuvette and therefore quantity how much effect is the cuvette causing on the final readings.
If you were an organism that requires sunlight to grow, where might you live in a pond? Why?
Answer
- Along the banks of the pond, with shallow ends. This is to ensure maximum exposure to sunlight for growth because deep in water, sunlight penetration is poor and hence poor growth.
Explanation:
Aquatic organisms that requires sunlight to grow, must have majority of their shoot exposed to the sunlight to effectively absorb more sunlight. Sunlight has poor penetration water, hence an organism that is submerged may have stunted growth if sunlight is a main requirement for its survival. This is common for photosynthetic organisms with poor sunlight absorption in water.
What is a male and female gametophyte?
Answer
- Male and female gametophytes exists in flowering plants.
Male gametophyte is derived from the pollen grain or miscospore while the female gametophyte is derived from the megaspore ( is the embryo-sac).
Explanation:
The male gametophyte comes from the pollen grains through the pollen tube and all its cells are functional. The pollen tube carries two make gametes, both of which are involved in the process of fertilization. Female gametophyte’s growth takes place inside the mega sporangium and all cells are formed by a single growth phase.
Endolymph is the fluid found in the semicircular canals that are responsible for dynamic equilibrium.
Select one:
True
False
Answer
- True
Explanation:
- The semicircular canals are three ring-like extensions from the vestibule. They are responsible for dynamic equilibrium.
- When the head rotates, endolymph does not move as quickly as the head.
- The ear contains motion sensors with the fluid, that detects the movement of the head
If there are three copies of chromosome number 21, this condition is called?
Answer
- Down syndrome
Explanation:
This condition is called Down Syndrome. It is described as Trisomy 21; each cell has three copies of chromosome 21. Some people with this condition might be healthy or develop serious heart defects among other health issues. This is caused by an abnormal cell division resulting an extra pair of chromosome 21.
In polyQ and non-polyQ categories of Huntington disease, the Q is meant to refer to which of the following amino acids?
A. Lysine
B. Glutamine
C. Aspartate
D. Arginine
E. Tryptophan
Answer
- B. Glutamine
Explanation:
- In full, polyQ is used to refer to Polyglutamine. This is a group of neurodegenerative disorders caused by expanded CAG repeats.
- In coding, CAG codon represents the amino acid Glutamine, represented by a single letter Q.
- Huntington disease is a progressive brain disorder which causes loss of thinking ability.
Which of these conditions does not usually result in a metabolic acidosis with increased anion gap?
DKA
Diarrhea
Chronic renal failure
Ethylene glycol poisoning
Answer
- Diarrhea
Explanation:
Metabolic acidosis refers to the process that leads to accumulation of hydrogen ions and decrease in bicarbonate ions in the body. The common causes of metabolic acidosis include diabetic ketoacidosis (DKA), uremia, lactic acidosis, and ethylene glycol intoxication.
Toxicity of ethylene glycol is mediated by its metabolites which raises the anion gap metabolic acidosis. With diarrhea, the anion gap is normal
Reference
https://www.justintimemedicine.com/CurriculumContent/p/4954
The hormone glucagon is a water-soluble peptide hormone secreted by the pancreas; it acts primarily on liver cells. A molecule of glucagon is about the size of a small protein. How does glucagon move into and out of capillaries?
Group of answer choices
bulk flow
transcytosis
diffusion
venocongestion
None of the above
Answer
- transcytosis
Explanation:
Transcytosis is a process by which macromolecules are transported across the endothelium of capillaries. Glucagon is large-sized molecule which cannot diffuse through the capillaries, bulk flow does not involve crossing a barrier. Glucagon is captured in vesicles on one side of the capillaries, drawn across the cell and ejected on the other side where it initiates a cell response (transcytosis process).
How can adverse drug events be minimized?
Answer
- 1medication should be discontinued
2)number of prescribers should be reduced to avoid repeating prescriptions,
3administering medications that can help generate a low risk to adverse drug events
4drugs should be reconciled before giving the medications to patients,
Explanation:
- adverse drug events include adverse drug reactions, error in medication, therapeutic failure and also overdose of the drug
- when you withdraw medication, the symptoms of ADE reduces considerably. in cases of overdose, withdrawal of the drug reduces drug doses in the body hence minimizing adverse drug events.
- in cases of therapeutic error, minimizing prescribers helps reduce this error
Which two factors act together to determine a person’s normal resting heart rate?
I. The intrinsic rate at which Purkinje fibers generate action potentials
II. The amount of acetylcholine released by the adrenal medulla
III. The intrinsic rate at which the sinoatrial (SA) node generates action potentials
IV. Parasympathetic input from the Vagus nerve
V. The rate at which blood enters the left atrium
Answer
- III. The intrinsic rate at which the sinoatrial (SA) node generates action potentials
V. The rate at which blood enters the left atrium
Explanation:
- normal resting heart rate ranges between 60 and 100.
- the sinoatrial node provides impulses that allow the heart to contract and enter the left ventricle. SA node generates impulse which causes atrium to contract and pump blood into the ventricles.
- the entry of blood into left atrium means that the left atrium have relaxed hence bringing up state of normal action of the heart
