1.
The study of muscles is known as;
Correct Answer
C. C. Myology
Explanation
Myology is the study of muscles, including their structure, function, and diseases. It involves the examination of muscle tissues, their composition, and how they work together to produce movement in the body. This field of study helps in understanding muscle development, muscle disorders, and the effects of exercise on muscles.
2.
Which type of muscle is multi nucleated and has striations?
Correct Answer
A. A. Skeletal
Explanation
Skeletal muscle is multi nucleated and has striations. Skeletal muscles are attached to the bones and are responsible for voluntary movements of the body. The presence of multiple nuclei in skeletal muscle fibers is due to the fusion of multiple myoblasts during development. The striations are caused by the arrangement of contractile proteins, actin, and myosin, within the muscle fibers.
3.
Which type of muscle cell is uni-nucleated and is spindled shape?
Correct Answer
C. C. Smooth
Explanation
Smooth muscle cells are uni-nucleated and have a spindled shape. They are found in the walls of organs and blood vessels and are responsible for involuntary movements. Unlike skeletal and cardiac muscle cells, smooth muscle cells do not have striations and have a single nucleus.
4.
The functional property of which muscle type is voluntary?
Correct Answer
A. A. Skeletal
Explanation
Skeletal muscle is the only muscle type that is under voluntary control. This means that we have conscious control over the contraction and relaxation of skeletal muscles, allowing us to move our body parts as desired. Cardiac muscle, found in the heart, and smooth muscle, found in the walls of organs and blood vessels, are both involuntary muscles, meaning they contract and relax without conscious control.
5.
Which muscle type is highly branched and has intercalated discs?
Correct Answer
B. B. Cardiac
Explanation
Cardiac muscle is highly branched and has intercalated discs. These discs are specialized junctions that connect cardiac muscle cells together, allowing for coordinated contraction of the heart. The branching nature of cardiac muscle allows for a greater number of cells to be connected, increasing the efficiency and strength of the contractions. Smooth muscle does not have intercalated discs, and skeletal muscle is not highly branched. Therefore, the correct answer is b. Cardiac.
6.
Muscles of the heart wall are examples of which muscle type?
Correct Answer
B. B. Cardiac
Explanation
Cardiac muscles are the muscles of the heart wall. These muscles are unique to the heart and are responsible for the contraction and relaxation of the heart, allowing it to pump blood throughout the body. Unlike skeletal muscles, which are under voluntary control, cardiac muscles are involuntary and contract rhythmically to maintain the heart's pumping action. Smooth muscles, on the other hand, are found in organs like the stomach and intestines, and are responsible for involuntary movements like digestion.
7.
The muscles of the hollow organs and the Iris are examples of which muscle type?
Correct Answer
C. C. Smooth
Explanation
Smooth muscles are found in the walls of hollow organs such as the stomach, intestines, bladder, and blood vessels. They are also present in the iris of the eye. Smooth muscles are involuntary muscles, meaning they are not under conscious control. They contract and relax to help with the movement of substances through the organs and to regulate the size of the iris, controlling the amount of light entering the eye. Therefore, the muscles of the hollow organs and the iris are examples of smooth muscles.
8.
Fusiform single cells are structural properties of which muscle type?
Correct Answer
C. C. Smooth
Explanation
Fusiform single cells are structural properties of smooth muscle. Smooth muscle is characterized by its spindle-shaped cells, known as fusiform cells, which are elongated and tapered at both ends. These cells are arranged in sheets or bundles and are responsible for involuntary movements in various organs and tissues of the body, such as the walls of blood vessels, the digestive system, and the respiratory system. Skeletal muscle, on the other hand, is composed of long, cylindrical, multinucleated fibers, while cardiac muscle consists of branching, interconnected cells with a striated appearance.
9.
Which is not an example of a smooth muscle?
Correct Answer
D. D. Pectoralis
Explanation
The pectoralis muscle is not an example of a smooth muscle. Smooth muscles are involuntary muscles found in the walls of organs and blood vessels. They are responsible for the contraction and relaxation of these structures. The stomach and iris are examples of smooth muscles, as they are both involuntary muscles that control movement and dilation. Arrector pili muscles are also smooth muscles, responsible for causing hair to stand on end. However, the pectoralis muscle is a skeletal muscle, which is a type of voluntary muscle responsible for movement and stability of the skeletal system.
10.
The structure of a muscle is comprised from which components?
Correct Answer
E. E. All of the above
Explanation
The correct answer is e. All of the above. The structure of a muscle is comprised of skeletal muscle tissue, connective tissue, nervous tissue, and blood. Skeletal muscle tissue is responsible for the actual contraction of the muscle. Connective tissue provides support and connects the muscle to other structures. Nervous tissue allows for the transmission of signals that control muscle contraction. Blood supplies oxygen and nutrients to the muscle tissue. Therefore, all of these components are necessary for the structure and function of a muscle.
11.
Layers of dense connective tissue are called?
Correct Answer
D. D. Fascia
Explanation
Fascia refers to the layers of dense connective tissue in the body. It surrounds muscles, organs, and other structures, providing support and protection. The other options, perimysium, epimysium, and endomysium, are also types of connective tissue but have specific roles in relation to muscles. Perimysium surrounds bundles of muscle fibers, epimysium surrounds entire muscles, and endomysium surrounds individual muscle fibers. Therefore, the correct answer is d. Fascia.
12.
The layer of connective tissue around the entire muscle?
Correct Answer
B. B. Epimysium
Explanation
The correct answer is "b. Epimysium". The epimysium is the layer of connective tissue that surrounds the entire muscle. It provides support and protection to the muscle, as well as helps to transmit force generated by the muscle to the surrounding structures. It is the outermost layer of connective tissue in the muscle and is continuous with the tendons that attach the muscle to the bone.
13.
Which layer surrounds individual Fascicles within each muscle?
Correct Answer
A. A. Perimysium
Explanation
The perimysium is the connective tissue layer that surrounds individual fascicles within each muscle. It provides support and protection to the fascicles and helps to maintain their shape and organization within the muscle. The perimysium also contains blood vessels and nerves that supply the fascicles, allowing for communication and nutrient exchange.
14.
Which is the plasma membrane of the cell?
Correct Answer
A. Sarcolemma
Explanation
The correct answer is Sarcolemma. The sarcolemma is the plasma membrane of a muscle cell. It surrounds and protects the cell, regulating the movement of substances in and out of the cell. The sarcolemma is essential for muscle contraction and plays a crucial role in maintaining the integrity and function of the muscle cell.
15.
Which are the little fibers stuffed within the Sarcoplasm?
Correct Answer
C. Myofibils
Explanation
Myofibils are the little fibers that are stuffed within the sarcoplasm. The sarcoplasm is the cytoplasm of a muscle cell, and it contains various structures including myofibils. Myofibils are long, cylindrical structures made up of smaller units called sarcomeres, which are responsible for muscle contraction. Therefore, myofibils are the correct answer to the question.
16.
Which is the cytoplasm of the muscle fiber?
Correct Answer
B. Sarcoplasm
Explanation
The sarcoplasm is the cytoplasm of the muscle fiber. It contains various organelles, such as mitochondria and the endoplasmic reticulum, which are necessary for muscle contraction and energy production. The sarcoplasm also contains myofibrils, which are made up of sarcomeres and are responsible for muscle contraction. The sarcolemma, on the other hand, is the cell membrane of the muscle fiber, while sarcomeres are the basic structural units of myofibrils. Therefore, the correct answer is sarcoplasm.
17.
Which is the structural and functional unit of the muscle?
Correct Answer
D. Sarcomeres
Explanation
Sarcomeres are the structural and functional units of muscles. They are responsible for muscle contraction and are composed of thick and thin filaments. Sarcomeres are arranged end to end within muscle fibers, allowing them to contract and relax, resulting in movement. The sarcomere consists of various proteins, including actin and myosin, which interact to generate the force necessary for muscle contraction.
18.
Sarcomeres contain which two structural proteins?
Correct Answer
A. Myosin & Actin
Explanation
Sarcomeres, the basic units of muscle contraction, contain two structural proteins: myosin and actin. Myosin is a thick filament protein that interacts with actin during muscle contraction, while actin is a thin filament protein that provides the structural framework for the sarcomere. Together, myosin and actin play a crucial role in muscle contraction and movement.
19.
The thick filaments of the Myofibrils are known as?
Correct Answer
A. Myosin
Explanation
Myosin is the correct answer because it is the protein that makes up the thick filaments in the myofibrils. These thick filaments are responsible for muscle contraction. Myosin interacts with actin, another protein, to generate the force needed for muscle movement. Tropomyosin and troponin are proteins involved in regulating muscle contraction, but they are not the main components of the thick filaments.
20.
The thin filaments of the Myofibrils are known as?
Correct Answer
D. Actin
Explanation
The thin filaments of the Myofibrils are known as Actin. Actin is a protein that plays a crucial role in muscle contraction. It forms the backbone of the thin filaments and interacts with myosin to generate force during muscle contraction. Actin filaments slide past myosin filaments, resulting in the shortening of the muscle fibers and the overall contraction of the muscle.
21.
Which band is made of overlapping thick and thin filaments?
Correct Answer
B. A band
Explanation
The A band is made of overlapping thick and thin filaments. The thick filaments are composed of myosin, while the thin filaments are composed of actin. The overlapping arrangement of these filaments gives the A band its characteristic appearance.
22.
Which bands are attached to the Z lines and made of Actin?
Correct Answer
A. I band
Explanation
The I band is the correct answer because it is the region of the sarcomere where only thin actin filaments are present. The Z lines, which are attached to the ends of the sarcomere, serve as attachment points for the actin filaments. Therefore, the I band is the band that is directly attached to the Z lines and made of actin.
23.
What lies in the center of the A bands and consists of Myosin filaments only?
Correct Answer
C. H zone
Explanation
The H zone is the correct answer because it is located in the center of the A bands and consists of Myosin filaments only. The H zone is a lighter region within the A band where only Myosin filaments are present, while the I band contains only Actin filaments. The Z discs are structures that anchor the Actin filaments and separate the sarcomeres, but they do not consist of Myosin filaments.
24.
All components of a Sacromere lie between 2 adjacent?
Correct Answer
D. Z discs
Explanation
The Z discs are the structures that mark the boundaries of each sarcomere, which is the basic contractile unit of a muscle fiber. All other components of a sarcomere, including the I bands, A bands, and H zone, are located between two adjacent Z discs. Therefore, the correct answer is Z discs.
25.
A motor neuron and the muscle fiber it contros create what?
Correct Answer
D. Motor unit
Explanation
A motor unit is created when a motor neuron and the muscle fiber it controls work together. The motor neuron sends signals to the muscle fiber, causing it to contract. This coordinated contraction of the muscle fiber is what creates the motor unit.
26.
The contracting of Sarcomeres and the pulling of muscles against its attachment is known as?
Correct Answer
B. Sliding Filament theory
Explanation
The correct answer is Sliding Filament theory. This theory explains how muscles contract by the interaction between actin and myosin filaments within the sarcomeres. During muscle contraction, the myosin filaments slide past the actin filaments, causing the sarcomeres to shorten and the muscles to contract. This process is responsible for the movement and pulling of muscles against their attachments.
27.
Which are the regulatory proteins?
Correct Answer(s)
B. Tropomsosin
C. Troponin
Explanation
The regulatory proteins mentioned in the options are tropomyosin and troponin. These proteins are involved in regulating muscle contraction. Tropomyosin is a long, filamentous protein that wraps around actin filaments in muscle cells, blocking the myosin-binding sites on actin and preventing muscle contraction. Troponin is a complex of three subunits that binds to tropomyosin and helps in regulating muscle contraction by exposing the myosin-binding sites on actin when calcium ions are present. Therefore, both tropomyosin and troponin are important regulatory proteins involved in muscle contraction.
28.
The contractile protein that consists of two strands of “golf heads”?
Correct Answer
A. Myosin
Explanation
Myosin is the correct answer because it is a contractile protein that consists of two strands, often referred to as "golf heads." These golf head-like structures are responsible for the interaction between myosin and actin filaments, leading to muscle contraction. Tropomyosin and troponin are regulatory proteins that are associated with actin filaments, but they do not have the same structure as myosin. Therefore, myosin is the most appropriate answer in this context.
29.
Which is the contractile protein with a myosin binding site?
Correct Answer
D. Actin
Explanation
Actin is the contractile protein that contains a myosin binding site. Myosin and actin are the two main proteins involved in muscle contraction. Myosin binds to actin to form cross-bridges, which generate the force required for muscle contraction. Actin filaments slide past myosin filaments, causing muscle fibers to shorten and contract. Tropomyosin and troponin are regulatory proteins that are associated with actin and help regulate the interaction between actin and myosin, but they do not directly contain the myosin binding site.