All MCAT Biology Resources
Example Questions
Example Question #1 : Types Of Muscle Cells
Which answer correctly mactches an organ or structure with the type of muscle found there?
The stomach—cardiac muscle
The heart—skeletal muscle
The bladder—smooth muscle
The small intestine—skeletal muscle
The aorta—cardiac muscle
The bladder—smooth muscle
Smooth muscle is found is the bladder, intestines, blood vessels, and a lot of other places that have involuntary motion. Skeletal muscle connects bones and muscles and allows us to move things voluntarily. Cardiac muscle is found in one place—the heart; therefore, the only correct match is the bladder to smooth muscle.
Example Question #2 : Types Of Muscle Cells
How many different types of muscle tissue are there in the human body?
Three
Four
None of these
Two
One
Three
There are three classifications of muscle tissue: skeletal, cardiac, and smooth. A major distinction between these groups is that only skeletal muscle can be voluntarily controlled. Smooth muscle (such as that around blood vessels) and cardiac muscle (in the heart) are not consciously controlled. Each muscle type is unique to its specific function.
Example Question #3 : Types Of Muscle Cells
Which muscle tissue type allows for voluntary control?
None of these
Cardiac
Skeletal
Smooth
Rough
Skeletal
Skeletal muscle is the only tissue type that allows for voluntary control; cardiac and smooth do not. Unlike the muscles in your arm, you cannot simply will the other muscle types to work. Think about it: you cannot stop your heart from pumping simply by trying to.
Example Question #4 : Types Of Muscle Cells
Striations are alternating light and dark bands seen in muscle cells under a microscope. What type of muscle tissue does not have striations?
All of these
Smooth
None of these
Cardiac
Skeletal
Smooth
Smooth muscle is the only muscle type that does not have striations. Striated muscle cells can contract rapidly, but cannot sustain this activity for long. Smooth muscle, however, uses slow contractions and is resistant to fatigue from repetitive work.
Example Question #5 : Types Of Muscle Cells
Which muscle tissue type has the most nuclei per fiber?
Skeletal
All of these
Smooth
Cardiac
None of these
Skeletal
Skeletal muscle tissue has the most nuclei out of the different types. Cardiac has one or two nuclei per fiber, and smooth muscle cells only have one. This is because of the high metabolic demands of these cells. There is a constant need for protein production and repairs to maintain muscle tissue, processes which originate in the nucleus. It makes sense that skeletal muscle, which is most active and has the highest energy demands, has the greatest number of nuclei.
Example Question #6 : Types Of Muscle Cells
There are 3 types of muscle: skeletal, smooth, and cardiac.
Which of these muscle types can humans control voluntarily?
Cardiac and smooth muscle
Skeletal muscle
Smooth muscle
Skeletal and cardiac muscle
All 3 muscle types can be fully controlled
Skeletal muscle
Skeletal muscle is the only type of muscle that can be controlled voluntarily. Skeletal muscle is the muscle type used to control the movement of our bones (and therefore our bodies). An exception to this rule is that smooth muscle can be controlled by some individuals, but to a extremely limited capacity.
Example Question #3 : Types Of Muscle Cells
Which of the following statements is true about the three muscle types?
All muscle types require calcium in order to contract.
All muscle types have mutlinucleated cells.
Only one type uses the sarcomere as the functional unit.
Only one type is controlled voluntarily.
Only one type is controlled voluntarily.
The only type of muscle tissue that can be controlled voluntarily is skeletal muscle tissue. Both skeletal and cardiac muscle tissue have the sarcomere as the functional unit, and only skeletal muscle has multinucleated cells. Smooth muscle does not have troponin, and therefore does not require calcium in order to contract.
Example Question #1 : Types Of Muscle Cells
Which of the three muscle types is both striated and multinucleated?
Skeletal muscle
Cardiac muscle
Smooth muscle
Both skeletal and cardiac muscle are striated and multinucleated
Skeletal muscle
The first requirement of this question is that the muscle type be striated. Striated muscle can be identified by the presence of alternating dark and light bands, caused by the repetition of sarcomeres, the basic muscle units composed of actin and myosin. Both cardiac and skeletal muscle types are striated.
The second requirement is that the muscle type must be multinucleate, meaning that individual cells have fused to form larger units with more than one nucleus. The only muscles with multinucleate cells are skeletal muscles, so that is our solution.
Example Question #5 : Types Of Muscle Cells
Skeletal muscle and cardiac muscle are similar in that they both __________.
are striated
are attached to bone
are multinucleated cells
have intercalated discs
are striated
Cardiac muscle and skeletal muscle are both composed of sarcomeres. This layout gives both muscle types a striated appearance, alternating dark bands of myosin with lighter bands of actin. Only cardiac muscle has intercalated discs and skeletal muscle is the only type that is multinucleated. No muscle type is attached directly to bone, but skeletal muscle is linked to bone via tendons.
Example Question #261 : Biology
All of the following are characteristics of cardiac muscle except __________.
striated appearance
autonomic regulation
electrical synapses between nerve and muscle fibers
use of calcium
electrical synapses between nerve and muscle fibers
Cardiac muscle is organized into sarcomeres, giving it a striated appearance, and cardiac contraction is strongly dependent on calcium concentrations and release. While the heart is capable of beating without nervous innervation, autonomic regulation via the parasympathetic nervous system mediates the frequency of cardiac stimulation from the sinoatrial (SA) node.
Signals from the parasympathetic nervous system travel to the cardiac muscle via chemical synapses, by use of a neurotransmitter. Signals from one cardiac fiber to another are transmitted via electrical synapses, or gap junctions, the allow proliferation of the signal without a chemical intermediate.