MCAT Biology Question — Muscle Types
- Mar 06, 2017
- MCAT Question of the Day
Mono-nucleated muscle cells are a predominant muscle fiber found in all of the following EXCEPT:
- the stomach
- the pharynx
- the heart
- the lungs
Click for Explanation
This question is testing your familiarity with the predominant muscle cell types found in various structures or organs within the body. To answer this question, you must know the characteristics of the three different muscle types: 1) skeletal, 2) cardiac, and 3) smooth. Skeletal muscle is striated, multi-nucleated, and under voluntary control and is typically attached to bones and cartilages. Cardiac muscle is involuntary, striated, and mono-nucleated and is found only in the heart. Smooth muscle is involuntary, mono-nucleated and non-striated is generally associated with viscera.
Since skeletal muscles contain only multi-nucleated cells, the correct answer to this question must be a structure that is under voluntary control. The stomach and the lungs are internal organs found in the thoracic and abdominal cavities. These visceral organs are involuntary and consist primarily of smooth muscle fibers eliminating choices A and D. The heart is also involuntary and contains mostly cardiac muscle eliminating answer choice C.
The pharynx is part of the digestive tract and is located above the esophagus. Both the pharynx and the upper third of the esophagus consist mostly of skeletal muscle, while the rest of the digestive system is controlled by smooth muscle. Since the pharynx contains primarily skeletal muscle, the cells are multi-nucleated. Thus the correct answer is B.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.
Search the Blog
Interested in our Online MCAT Course, One-on-One MCAT Tutoring or Med admissions packages? Set up a free consultation with one of our experienced Senior Student Advisors.Schedule Now
MCAT Blog What's on the MCAT?
MCAT Blog How to Review MCAT Full Lengths
Free MCAT Practice AccountNeed great MCAT practice?
Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.Learn More