MCAT practice questions

[mcat_gold]

If the sum of all the forces acting on a moving object is zero, the object will:

A. decelerate and stop.
B. accelerate uniformly.
C. change the direction of its motion.
D. continue moving with constant velocity.

Answer: D

Explanation: For something to change direction or accelerate there must be a net force acting on it (Newton’s 2nd Law).
Also, Newton’s 1st Law states that an object in motion will stay in motion at constant velocity (a form of inertia) unless acted upon by a net (an unbalanced) force.

See more MCAT questions here:
MCAT 2015 sample questions http://www.mcat-prep.com/mcat-2015-chan ... eQuestions
Pinterest http://www.pinterest.com/mcatprep/mcat- ... questions/

[mcat_gold]

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

Explanation:
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.

More MCAT 2015 sample questions here http://www.mcat-prep.com/mcat-2015-changes-preparation/#MCAT2015SampleQuestions

[mcat_gold]

Choose the molecule that has the correct dipole orientation.

See image here https://s-media-cache-ak0.pinimg.com/originals/e4/ac/10/e4ac1050268e9f96246feeed0f057b58.jpg

Correct Answer: B
The polarization of a bond is determined by the relative electronegativity of each particular atom. As Cl is more electronegative than a hydrogen atom, so the dipole moment points towards the Cl atom along the H-Cl bond. As a good memory guide, from your physics review, you would know that an electric field line always points away from a positive charge.

[mcat_gold]

Gold Standard MCAT sample Psychology question with explanation:

How would Jenny, a salesperson at an organic pre-made meals company, use the door-in-the-face technique to persuade people who do not want to subscribe to purchase the meals?

A. Ask individuals if they want to subscribe to the meals for two years, and then later scale it down to a month.
B. Ask individuals if they want to subscribe to the meals, and if they are interested, say that they should do so immediately because the 15% discount will end within two days.
C. Ask individuals if they want to subscribe to the meals using a trial basis of one week. Once they agree, she would then ask if they want a six-month subscription.
D. Ask individuals if they want to subscribe to the meals and then hand out a flyer of endorsements given by famous chefs.

Correct Answer: A
Explanation
Foundational Concept: 7. Biological, psychological, and sociocultural factors influence behavior and behavior change
Content Category: 7B. Social processes that influence human behavior
Scientific Reasoning and Inquiry Skill: 1 Knowledge of Scientific Concepts and Principles

With the door-in-the-face technique, the requester starts with a very large appeal and more often than not will be denied (the door will be slammed in his/her face). The requester then makes a concession and offers a second request, upon which the person being asked will feel that he/she should also make a concession and will more likely accept the offer.

Distractors

B. This is incorrect. This scenario describes a persuasive technique that relies on using a deadline such as a sale that will end in two days. This produces feelings of anxiety that the same deal will not be offered in the future.

C. This is incorrect. This scenario illustrates the foot-in-the-door technique, which involves asking for a smaller request. Once the requester has the individual’s attention and the requester thus has his/her foot in the door, the requester makes a larger request.

D. This is incorrect. This scenario relies on using testimonials that demonstrate the legitimacy and credibility of the product.

[goldstandard_mcat]

The human placenta is implicated in all of the following EXCEPT one. Which one is the EXCEPTION?

A. Transporting urea and carbon dioxide from the fetus to the mother
B. Initiating uterine contraction prior to birth
C. Synthesizing glycogen to be used as an energy source for the fetus
D. Secreting estrogen and progesterone during the gestation period

Correct answer: B
Explanation:

The placenta is formed from cells of the chorion of the embryo and the maternal endometrium, following implantation of the fertilized egg into the uterus. The placenta has 3 main functions:

1. the transfer of nutrients from the mother to the fetus and the transfer of wastes from the fetus to the mother (answer choice A.);

2. the production of nutrients for energy (answer choice C.), and

3. the production and secretion of hormones such as hCG, estrogen and progesterone (answer choice D.).

Note that IgG is the only isotype that can pass through the human placenta. An increase in the hormone oxytocin, produced by the posterior pituitary, is associated with the initiation of uterine contractions.