Student Doc Forum

MCAT Forum | USMLE Forum

MCAT preparation and implications of MCAT scores.

Re: MCAT practice questions

Sat Nov 12, 2016 5:37 am

MCAT practice questions

Re: MCAT practice questions

Mon Nov 21, 2016 7:08 am

So these practice questions are very useful, but I am a visual learner, so I tend to use YouTube a lot to learn.

One of my friends recently started this playlist where he has been posting one question a day and I have found it to be extremely helpful. ... cn&index=1

Do you guys have any other channels for MCAT practice problems that would help?

Re: MCAT practice questions

Thu Dec 29, 2016 3:31 am

What is the name and frequency of the majority of the electromagnetic waves produced during non–rapid eye movement (NREM) sleep stage 4 (name, frequency, respectively)?

A. Delta, <4 Hz
B. Theta, 4–7 Hz
C. Alpha, 8–12 Hz
D. Beta, 13–24 Hz

Correct Answer: A

Foundational Concept: 6 Biological, psychological, and sociocultural factors influence the ways that individuals perceive, think about, and react to the world
Content Category: 6B Making sense of the environment
Scientific Reasoning and Inquiry Skill: 1 Knowledge of Scientific Concepts and Principles

A is correct. During stage 4, 50% or more of the waves are delta waves, which have a frequency of 4 Hz or less. During this stage, sleep is deepest and the waves are slowest and largest in amplitude. Human growth hormone is released, boosting restorative biological processes; metabolic functions slow down; breathing becomes slow and regular; muscular activity is limited; and no dreams are thought to occur. It is very difficult to wake a person up during this stage, and the sleeper will wake up confused. Somnambulism and sleep terrors can occur.

B. This is incorrect. Theta waves are produced during sleep stages 1, 2, and 3; very deep relaxation; and meditative states. During stage 3, there are 50% or more theta waves, which have a frequency between 4 and 8 Hz. In stage 2, the electromagnetic phenomena of spindles and K-complexes occur.

C. This is incorrect. Alpha waves are emitted during awake states of overall deep relaxation, such as during meditation, hypnosis, and listening to music, and during REM and non-REM sleep stage 1. The person is conscious, feels drowsy, or experiences light sleep.

D. This is incorrect. Beta waves characterize the normal waking, conscious, thinking, focused, and alert psychophysiological state of consciousness. They are also produced under stressful situations and during REM.

For more free MCAT sample questions, visit [url][/url]

Re: MCAT practice questions

Wed Jan 25, 2017 5:39 pm

Oxidative phosphorylation is best described as:

A. the process in which ATP is formed as electrons are transferred from electron carriers to oxygen.
B. the process to repay the oxygen debt.
C. the process in which ATP is formed as pyruvate is converted into acetyl CoA.
D. the process in which ATP is formed as acetyl CoA is completely oxidized to carbon dioxide.

Correct answer: A

Oxidative phosphorylation is defined by A; B may be true but it is an inadequate description of oxidative phosphorylation; C describes the intermediate step between glycolysis and the Krebs cycle; D describes the Krebs cycle.

For more free MCAT practice questions, visit [url][/url]

Re: MCAT practice questions

Mon Nov 13, 2017 9:32 pm

An anesthesiologist is preparing an anesthetic mixture at standard pressure and 25 oC which contains 564 torr N2O and 12.4 torr of the halogenated anesthetic halothane (CHClBrCF3). If the mixture contains only these two compounds and oxygen, what is the partial pressure of oxygen in the mixture at 25 oC?

A. 124 torr
B. 154 torr
C. 184 torr
D. 214 torr

Correct Answer: C
Explanation: Standard pressure is 1 atm, 101.3 kPa or 760 mmHg or torr.
Using Dalton's law [pp = partial pressure]:
pp(N2O) + pp(halothane) + pp(O2) = 760
564 + 12.4 + pp(O2) = 760
pp(O2) = 183.6 = approx. 184 torr

MCAT practice question from Gold Standard MCAT