1.
Muscle contractions depend on:
Correct Answer
F. Myofilaments: both actin and myosin
Explanation
Muscle contractions depend on myofilaments, specifically actin and myosin. Actin and myosin are proteins found in muscle fibers that interact with each other, causing the muscle to contract. Actin forms thin filaments, while myosin forms thick filaments. During muscle contraction, myosin heads bind to actin, forming cross-bridges. These cross-bridges then pull the actin filaments, causing them to slide past the myosin filaments and resulting in muscle contraction. Therefore, myofilaments, which consist of both actin and myosin, are essential for muscle contractions to occur.
2.
Which below are types of muscle tissue--check all that apply
Correct Answer(s)
A. Skeletal
B. Smooth
C. Cardiac
Explanation
The correct answer is skeletal, smooth, and cardiac. These are the three main types of muscle tissue found in the human body. Skeletal muscle is attached to bones and allows for voluntary movement. Smooth muscle is found in the walls of organs and blood vessels, and is responsible for involuntary movements. Cardiac muscle is found in the heart and is responsible for pumping blood. None of the above is not a correct answer because there are indeed different types of muscle tissue in the body.
3.
which below are elongated and are called muscle fibers?
Correct Answer(s)
A. Skeletal
B. Smooth
Explanation
Skeletal and smooth muscles are elongated muscle fibers. Skeletal muscles are attached to the bones and are responsible for voluntary movements. Smooth muscles are found in the walls of organs and blood vessels and are responsible for involuntary movements. Cardiac muscles, on the other hand, are not elongated muscle fibers but rather specialized muscle tissue found only in the heart. Therefore, the correct answer is skeletal and smooth muscles.
4.
Which term below means: "muscle plasma membrane" ?
Correct Answer
C. Sarcolemma
Explanation
The term "sarcolemma" refers to the muscle plasma membrane. It is the outer membrane surrounding muscle fibers and is responsible for maintaining the integrity and function of the muscle cell. The sarcolemma controls the movement of substances in and out of the muscle cell and plays a crucial role in muscle contraction and communication between muscle cells.
5.
Which term (s) below mean: "a contractile protein of muscle" ?
Correct Answer
F. Myofilaments: both actin and myosin
Explanation
The term "myofilaments" refers to both actin and myosin, which are contractile proteins found in muscle. Actin and myosin work together to generate the force needed for muscle contraction. The other terms listed in the question, such as sarcolemma, sarcoplasm, and striations, are not specifically related to contractile proteins but rather to other components or features of muscle cells.
6.
Muscle Tissues:which type of muscle tissue:is controlled voluntarily
Correct Answer
D. Skeletal
Explanation
Skeletal muscle tissue is controlled voluntarily. This type of muscle tissue is found attached to the bones and is responsible for the movement of the body. It is under conscious control, meaning that we can choose to contract or relax these muscles at will. Skeletal muscles are composed of long, cylindrical cells called muscle fibers that are organized into bundles. These muscles are striated, meaning they have a striped appearance due to the arrangement of actin and myosin filaments.
7.
Which term below means: "cytoplasm of a muscle cell" ?
Correct Answer
D. Sarcoplasm
Explanation
The term "sarcoplasm" refers to the cytoplasm of a muscle cell. It is the fluid-filled space within the muscle fiber that contains various organelles, including mitochondria, nuclei, and myofibrils. The sarcoplasm plays a crucial role in providing the necessary nutrients and energy for muscle contraction.
8.
Muscle Tissues:which type (s) of muscle tissue:has striations
Correct Answer(s)
A. Skeletal
C. Cardiac
Explanation
Skeletal and cardiac muscles both have striations. Skeletal muscles are attached to bones and are responsible for voluntary movements. Cardiac muscles are found in the walls of the heart and are responsible for pumping blood. Smooth muscles, on the other hand, do not have striations and are found in the walls of organs such as the stomach, intestines, and blood vessels. Therefore, the correct answer is skeletal and cardiac muscles.
9.
Muscle Tissues:which type (s) of muscle tissue:contracts rapidly but tires easily
Correct Answer
A. Skeletal
Explanation
Skeletal muscle tissue is the correct answer because it contracts rapidly but tires easily. Skeletal muscles are responsible for voluntary movements and are attached to the skeleton. They are made up of long, cylindrical cells called muscle fibers that are striated in appearance. Skeletal muscles are under conscious control and can contract quickly, allowing for rapid movements. However, they also fatigue easily, as they require a lot of energy to sustain their contractions. Smooth muscle tissue, found in organs like the intestines, contracts slowly and rhythmically. Cardiac muscle tissue, found in the heart, contracts continuously and involuntarily.
10.
Muscle Tissues:which type (s) of muscle tissue:occurs only in the heart
Correct Answer
C. Cardiac
Explanation
Cardiac muscle tissue is the correct answer because it is the only type of muscle tissue that occurs exclusively in the heart. Skeletal muscle tissue is found attached to bones and is responsible for voluntary movements, while smooth muscle tissue is found in the walls of organs and blood vessels and is responsible for involuntary movements. Therefore, neither skeletal nor smooth muscle tissue occurs only in the heart.
11.
Muscle Tissues:which type (s) of muscle tissue:is striated like skeletal muscle but is not voluntary
Correct Answer
C. Cardiac
Explanation
Cardiac muscle tissue is striated like skeletal muscle but is not voluntary. Unlike skeletal muscle, which is under conscious control, cardiac muscle is involuntarily controlled by the autonomic nervous system. Cardiac muscle is found only in the heart and is responsible for pumping blood throughout the body. Its striated appearance is due to the arrangement of contractile proteins within the cells. Smooth muscle, on the other hand, is also involuntary but lacks the striations seen in both skeletal and cardiac muscle.
12.
Muscle Tissues:which type (s) of muscle tissue:Found in the walls of hollow visceral organs, such as the stomach, urinary bladder, and respiratory passages
Correct Answer
B. Smooth
Explanation
Smooth muscle tissue is found in the walls of hollow visceral organs such as the stomach, urinary bladder, and respiratory passages. Unlike skeletal muscle tissue, which is attached to bones and allows voluntary movement, smooth muscle tissue is involuntary and contracts slowly and rhythmically. Cardiac muscle tissue is found only in the heart and has a unique structure and function. Therefore, the correct answer is smooth muscle tissue.
13.
Muscle Tissues:which type (s) of muscle tissue:forces food and other substances through internal body channels
Correct Answer
B. Smooth
Explanation
Smooth muscle tissue is responsible for the movement and contraction of various internal body channels, such as the digestive tract, blood vessels, and airways. Unlike skeletal muscle tissue, which is voluntary and under conscious control, smooth muscle tissue is involuntary and functions automatically. Cardiac muscle tissue, found only in the heart, is responsible for pumping blood and is not involved in the movement of food and substances through internal body channels. Therefore, the correct answer is smooth muscle tissue.
14.
Muscle Tissues:which type (s) of muscle tissue:is not striated and is involuntary
Correct Answer
B. Smooth
Explanation
Smooth muscle tissue is not striated and is involuntary. Unlike skeletal muscle tissue, which is attached to bones and allows for voluntary movement, smooth muscle tissue is found in the walls of internal organs, blood vessels, and the respiratory system. It is responsible for involuntary movements such as peristalsis (contractions of the digestive system) and regulating blood flow. Cardiac muscle tissue, on the other hand, is striated but is also involuntary, as it controls the contraction of the heart. Therefore, the correct answer is smooth muscle tissue.
15.
Muscle characteristics:which term below is this characteristic of muscle tissue?The ability to receive and respond to stimuli
Correct Answer
A. Excitability or irritability
Explanation
Excitability or irritability refers to the characteristic of muscle tissue that enables it to receive and respond to stimuli. This means that muscle cells can detect and react to various signals, such as nerve impulses, hormones, or changes in the environment. This characteristic allows muscles to contract and generate force in response to these stimuli, enabling movement and other physiological functions.
16.
Muscle characteristics:which term below is this characteristic of muscle tissue?The ability to shorten forcibly
Correct Answer
B. Contractility
Explanation
Contractility is the correct answer because it refers to the ability of muscle tissue to shorten forcibly when it receives a stimulus. This characteristic allows muscles to generate tension and produce movement in the body. Excitability or irritability refers to the ability of muscles to respond to stimuli, extensibility refers to the ability of muscles to be stretched, and elasticity refers to the ability of muscles to return to their original shape after being stretched.
17.
Muscle characteristics:which term below is this characteristic of muscle tissue?the ability to be stretched or extended
Correct Answer
C. Extensiblity
Explanation
The term "extensibility" refers to the ability of muscle tissue to be stretched or extended. This characteristic allows muscles to lengthen and adapt to changes in movement or posture. It is an essential feature for muscles to be able to contract and relax effectively.
18.
Muscle characteristics:which term below is this characteristic of muscle tissue?the ability to recoil and resume the original resting length
Correct Answer
D. Elasticity
Explanation
Elasticity is the correct answer because it refers to the ability of muscle tissue to recoil and return to its original resting length after being stretched or contracted. This characteristic allows muscles to maintain their shape and function properly during movement and contraction.
19.
Muscle Tissues:which type (s) of muscle tissue:responsible for all locomotion
Correct Answer
A. Skeletal
Explanation
Skeletal muscle tissue is responsible for all locomotion in the body. This type of muscle tissue is attached to the bones and allows for voluntary movement of the body. It is responsible for actions such as walking, running, and lifting objects. Smooth muscle tissue, on the other hand, is found in the walls of organs and blood vessels, and is responsible for involuntary movements. Cardiac muscle tissue is specific to the heart and is responsible for pumping blood. Therefore, the correct answer is skeletal muscle tissue.
20.
Muscle Tissues:which type (s) of muscle tissue:responsible for coursing blood through the body
Correct Answer
C. Cardiac
Explanation
Cardiac muscle tissue is responsible for coursing blood through the body. Unlike skeletal and smooth muscles, cardiac muscles are found only in the heart. They have specialized properties that allow them to contract rhythmically and continuously, pumping blood throughout the circulatory system. This unique ability enables the heart to fulfill its crucial role in maintaining blood circulation and supplying oxygen and nutrients to the body's tissues. Therefore, cardiac muscle tissue is the correct answer for this question.
21.
Muscle Tissues:which type (s) of muscle tissue:helps maintain blood pressure and propels sustances through organs (i.e. food, feces)
Correct Answer
B. Smooth
Explanation
Smooth muscle tissue helps maintain blood pressure and propels substances through organs such as food and feces. Unlike skeletal muscle tissue, which is attached to bones and responsible for voluntary movements, smooth muscle tissue is found in the walls of hollow organs and blood vessels. It contracts rhythmically and involuntarily, allowing for the movement of substances through these structures. Cardiac muscle tissue, on the other hand, is specific to the heart and is responsible for its contractions. Therefore, the correct answer is smooth muscle tissue.
22.
Each muscle is a discrete organ composed of: (check all that apply)
Correct Answer(s)
A. Muscle tissue
B. Blood vessels
C. Nerve fibers
D. Connective tissue
Explanation
Muscles are composed of multiple components, including muscle tissue, blood vessels, nerve fibers, and connective tissue. Muscle tissue is the main component of muscles and is responsible for their contraction and movement. Blood vessels supply oxygen and nutrients to the muscle tissue, while nerve fibers transmit signals from the brain to the muscles, allowing for voluntary control of movement. Connective tissue provides support and structure to the muscles, helping to bind the different components together.
23.
Which below are connective tissue sheaths?
Correct Answer(s)
A. Endomysium--fine sheath of connective tissue composed of reticular fibers surrounding each muscle fiber
B. Perimysium--fibrous connective tissue that surrounds groups of fascicles
C. Epimysium--an overcoat of connective tissue that surrounds the whole muscle
Explanation
The connective tissue sheaths in muscles are important for providing support and structure to the muscle fibers. The endomysium is a fine sheath of connective tissue that surrounds each individual muscle fiber, composed of reticular fibers. The perimysium is a fibrous connective tissue that surrounds groups of fascicles, which are bundles of muscle fibers. The epimysium is an overcoat of connective tissue that surrounds the entire muscle. These connective tissue sheaths help to protect and strengthen the muscle fibers, allowing them to function properly.
24.
An overcoat of connective tissue that surrounds the whole muscle
Correct Answer
C. Epimysium
Explanation
The correct answer is Epimysium. Epimysium refers to the outermost layer of connective tissue that surrounds the entire muscle. It provides support and protection to the muscle fibers, as well as helps to maintain the shape of the muscle. The epimysium also connects the muscle to the surrounding tissues and structures.
25.
Fibrous connective tissue that surrounds groups of fascicles
Correct Answer
B. Perimysium
Explanation
Perimysium is the correct answer because it is the fibrous connective tissue that surrounds groups of fascicles. Fascicles are bundles of muscle fibers, and the perimysium acts as a protective sheath around these bundles, providing structural support and allowing for coordinated movement of the muscle fibers within each fascicle. The endomysium, on the other hand, surrounds individual muscle fibers, while the epimysium surrounds the entire muscle.
26.
Fine sheath of connective tissue composed of reticular fibers surrounding each muscle fiber
Correct Answer
A. Endomysium
Explanation
The fine sheath of connective tissue composed of reticular fibers surrounding each muscle fiber is called the endomysium. It provides support and protection to individual muscle fibers, as well as allows for the exchange of nutrients and waste products. The endomysium also helps to maintain the structural integrity of the muscle and allows for smooth muscle contraction.
27.
Each muscle is an organ true or false
Correct Answer
A. True
Explanation
Each muscle is considered an organ because it is made up of different tissues, such as muscle fibers, blood vessels, and connective tissues, all working together to perform a specific function. Organs are defined as structures composed of different tissues that work together to carry out specific functions in the body.
28.
Each muscle is served by:
Correct Answer
C. One nerve, one artery, and one or more veins
Explanation
Each muscle is served by one nerve, one artery, and one or more veins. This is because muscles require a constant supply of oxygen and nutrients, as well as the removal of waste products. The nerve provides the necessary signals for muscle contraction and coordination. The artery delivers oxygenated blood and nutrients to the muscle, while the veins carry deoxygenated blood and waste products away from the muscle. The presence of one or more veins ensures efficient removal of waste and adequate oxygenation of the muscle tissue.
29.
Wastes are washed away via:
Correct Answer
C. Veins
Explanation
Veins are responsible for carrying deoxygenated blood, waste products, and carbon dioxide back to the heart and lungs to be filtered and oxygenated. Therefore, it can be inferred that waste products are washed away via veins.
30.
Contracting fibers require continuous delivery of oxygen and nutrients via
Correct Answer
B. Arteries
Explanation
Arteries are responsible for delivering oxygen and nutrients to contracting fibers. These blood vessels have thick, elastic walls that allow them to carry oxygenated blood away from the heart and distribute it to various parts of the body, including the contracting muscles. Arteries also contain smooth muscle fibers that help regulate blood flow and maintain proper blood pressure. Therefore, the continuous delivery of oxygen and nutrients to contracting fibers is facilitated by arteries.
31.
Each muscle fiber is supplied with a ______ to control contractions
Correct Answer
A. Nerve
Explanation
Muscle fibers are controlled by nerves, which transmit electrical signals from the brain and spinal cord to the muscles. These signals stimulate the muscle fibers to contract and generate movement. Without nerves, the muscles would not receive the necessary instructions to contract and would be unable to perform their functions. Arteries and veins are responsible for transporting blood to and from the muscles, but they do not directly control muscle contractions.
32.
Whe muscles contract the moveable bone, the muscle's insertion moves toward the immovable bone, the muscle's origin
Correct Answer
A. True
Explanation
When muscles contract, they generate force that pulls on the moveable bone, causing it to move. The point where the muscle attaches to the moveable bone is called the insertion. As the muscle contracts, the insertion moves towards the immovable bone, which is called the origin of the muscle. This is because the muscle shortens as it contracts, pulling the insertion closer to the origin. Therefore, the statement "When muscles contract, the moveable bone moves towards the immovable bone, the muscle's origin" is true.
33.
Muscles attach:
Correct Answer(s)
A. Directly: epimysium of hte muscle is fused to the periosterum of the bone
B. Indirectly: connective tissue wrappings extend byond the muscle as a tendon or aponeurosis
Explanation
Muscles attach directly to bones through the fusion of the epimysium (the outer layer of connective tissue surrounding the muscle) with the periosteum (the outer layer of connective tissue surrounding the bone). This direct attachment provides stability and allows for efficient transfer of force from the muscle to the bone. Additionally, muscles can also attach indirectly to bones through tendons or aponeuroses, which are extensions of the connective tissue wrappings that extend beyond the muscle. These indirect attachments further enhance the strength and functionality of the muscle-bone connection.
34.
Which term below has numerous glycosomes and a unique oxygen-binding protein called myoglobin
Correct Answer
D. Sarcoplasm
Explanation
The sarcoplasm is the correct answer because it is the cytoplasm of muscle cells and contains numerous glycosomes, which store glycogen for energy production during muscle contraction. Additionally, the sarcoplasm contains myoglobin, a unique oxygen-binding protein that helps facilitate oxygen delivery to the muscle cells during exercise.
35.
An oxygen-binding protein
Correct Answer
G. Myoglobin
Explanation
Myoglobin is an oxygen-binding protein found in muscle cells. It is responsible for storing and transporting oxygen to the muscles. This protein has a higher affinity for oxygen than hemoglobin, allowing it to efficiently deliver oxygen to the muscles during periods of high demand, such as during exercise. Myoglobin also gives muscles their reddish color.
36.
Densly packed, rodlike contractile elements
Correct Answer
E. Myofibrils
Explanation
Myofibrils are densely packed, rodlike contractile elements found in muscle cells. They are composed of myofilaments, which include both actin and myosin. Myofibrils play a crucial role in muscle contraction by sliding the actin and myosin filaments past each other, resulting in muscle shortening and force generation. They are surrounded by the sarcoplasm, the cytoplasm of muscle cells, and are enclosed by the sarcolemma, the cell membrane of muscle cells. Myoglobin, a protein that binds and stores oxygen in muscle cells, is not directly related to myofibrils.
37.
These make up most of muscle volume
Correct Answer
E. Myofibrils
Explanation
Myofibrils are the correct answer because they are the structures that make up most of the volume of muscle. They are composed of smaller units called myofilaments, which include both actin and myosin. Myofibrils are responsible for muscle contraction and contain the contractile proteins actin and myosin. They are surrounded by sarcoplasm, which is the cytoplasm of muscle cells, and enclosed by the sarcolemma, which is the cell membrane of muscle fibers. Myoglobin, on the other hand, is a protein that stores oxygen in muscle cells and is not directly related to muscle volume.
38.
This is such that is perfectly aligned by a repeating seres of dark a bands and light i bands
Correct Answer
E. Myofibrils
Explanation
Myofibrils are structures within muscle cells that are responsible for muscle contraction. They are composed of repeating units called sarcomeres, which are made up of dark A bands and light I bands. The alignment of these bands creates a striated appearance in muscle tissue. Therefore, myofibrils perfectly align with a repeating series of dark A bands and light I bands, making them the correct answer.
39.
The smallest contractile unit of a muscle
Correct Answer
E. Sarcomere
Explanation
A sarcomere is the smallest contractile unit of a muscle. It is responsible for muscle contraction and consists of overlapping actin and myosin filaments. The actin and myosin filaments slide past each other during muscle contraction, shortening the sarcomere and causing the muscle to contract. The sarcomere is surrounded by the sarcolemma, which is the cell membrane of the muscle fiber, and contains the sarcoplasm, which is the cytoplasm of the muscle fiber. Myoglobin is a protein that stores oxygen in muscle cells, but it is not directly involved in muscle contraction.
40.
Composed of myofilments made up of contractile proteins
Correct Answer
E. Sarcomeres
Explanation
Sarcomeres are the basic functional units of muscle fibers, and they are composed of myofilaments made up of contractile proteins, specifically actin and myosin. These proteins work together to generate muscle contractions. Sarcomeres are responsible for the striated appearance of skeletal and cardiac muscles and play a crucial role in muscle contraction and relaxation.
41.
The region of a myofibril between two successive Z discs
Correct Answer
E. Sarcomeres
Explanation
Sarcomeres are the repeating units of a myofibril that are located between two successive Z discs. These structures are responsible for the contraction of muscle fibers. Sarcomeres contain both actin and myosin myofilaments, which slide past each other during muscle contraction. The other options, such as actin, myosin, sarcolemma, sarcoplasm, and myoglobin, are not specifically associated with the region between two Z discs.
42.
Extend the entire length of an A (dark) band
Correct Answer
A. Thick filaments
Explanation
Thick filaments are responsible for the dark appearance of the A band in a sarcomere. They extend the entire length of the A band and are composed of myosin protein. These filaments are larger in size and contribute to the overall structure and function of muscle contraction.
43.
Extend across the I (light) band and partway into the A (dark) band
Correct Answer
B. Thin filaments
Explanation
Thin filaments extend across the I (light) band and partway into the A (dark) band.