1.
What are the different types of muscles that are in our bodies?
Correct Answer
C. Cardiac, smooth, and skeletal
Explanation
The different types of muscles in our bodies are cardiac, smooth, and skeletal. Cardiac muscles are found in the heart and are responsible for pumping blood. Smooth muscles are found in the walls of organs and blood vessels, and they help with involuntary movements like digestion and blood flow. Skeletal muscles are attached to bones and are responsible for voluntary movements like walking and lifting.
2.
What is a neuromuscular junction?
Correct Answer
B. A motor neuron that allows communication between the muscle and the nervous system
Explanation
A neuromuscular junction is a motor neuron that allows communication between the muscle and the nervous system. This junction is where the motor neuron releases neurotransmitters that stimulate the muscle fibers to contract. The communication between the motor neuron and the muscle is essential for coordinating muscle movement and maintaining proper functioning of the nervous system.
3.
What are the differences between adduction and abduction of a muscle?
Correct Answer
A. Adduction allows for movement towards, whereas abduction allows for movement away from the middle of the body.
Explanation
Adduction refers to the movement of a body part towards the midline of the body, while abduction refers to the movement of a body part away from the midline of the body. Therefore, the correct answer states that adduction allows for movement towards the middle of the body, while abduction allows for movement away from the middle of the body.
4.
What two muscles work together to allow total movement of an appendage?
Correct Answer
D. Hamstring and quadricep
Explanation
The hamstring and quadricep muscles work together to allow total movement of an appendage. The hamstring muscles are located at the back of the thigh and are responsible for flexing the knee and extending the hip. The quadricep muscles are located at the front of the thigh and are responsible for extending the knee and flexing the hip. By working together, these muscles allow for a full range of movement in the leg, enabling activities such as walking, running, and jumping.
5.
What is the main function of the muscular system?
Correct Answer
C. To control the movements of the body
Explanation
The main function of the muscular system is to control the movements of the body. Muscles work together with the skeletal system to enable movement and provide stability and support to the body. They contract and relax to allow us to walk, run, lift objects, and perform various other activities. The muscular system also helps maintain posture and balance. While muscles do contribute to strength, their primary role is to facilitate and control movement rather than solely making humans strong.
6.
What is the fundamental unit of a muscle fiber?
Correct Answer
A. Sarcomere
Explanation
A sarcomere is the fundamental unit of a muscle fiber. It is the basic structural and functional unit of a muscle. Sarcomeres are composed of actin and myosin filaments, which slide past each other during muscle contraction. This sliding action is what allows muscles to shorten and generate force. Therefore, sarcomeres play a crucial role in muscle contraction and are considered the building blocks of muscle fibers.
7.
According to the Sliding- Filament Theory,
Correct Answer
A. A sarcomere will contract when a thin filament slides past a stationary thick filament.
Explanation
The Sliding-Filament Theory states that muscle contraction occurs when the thin filaments slide past the stationary thick filaments in a sarcomere. This occurs due to the interaction between the proteins actin and myosin. As myosin heads attach to actin, they pull the thin filaments towards the center of the sarcomere, causing it to contract. Therefore, a sarcomere will contract when a thin filament slides past a stationary thick filament.
8.
Which, if any, of the following muscles lacks striations?
Correct Answer
A. Smooth
Explanation
Smooth muscles lack striations. Unlike skeletal and cardiac muscles, smooth muscles do not have the organized pattern of alternating light and dark bands called striations. Smooth muscles are found in the walls of internal organs and blood vessels, and their contractions are involuntary.
9.
A cat is sitting in its bed outside when it sees a crow land in the backyard. When she starts to chase the bird, what muscles is the cat using?
Correct Answer
C. Cardiac and skeletal
Explanation
When a cat starts to chase a bird, it requires the coordination of both cardiac and skeletal muscles. Cardiac muscles are responsible for the contraction and relaxation of the heart, ensuring that blood is pumped efficiently throughout the body to provide oxygen and nutrients to the skeletal muscles. Skeletal muscles, on the other hand, are responsible for the movement of the cat's limbs and body, allowing it to run and jump. Therefore, both cardiac and skeletal muscles are used when a cat chases a bird.
10.
Voluntary muscles require this to contract.
Correct Answer
D. Neural stimulation
Explanation
Voluntary muscles require neural stimulation to contract. This means that the muscles need signals from the nervous system to initiate and control their contractions. Without neural stimulation, the muscles would not receive the necessary instructions to contract and therefore would remain relaxed. Neural stimulation allows for the coordination and control of voluntary muscle movements, enabling us to perform various actions and tasks.