Anatomy And Physiology Exam 2 Practice Test
Anatomy and Physiology form the two main branches of biology. This quiz is aimed at providing you all the content to practice for the exam. The quiz contains various questions that are sure to gauge your understanding of the subject. The quiz will be immensely helpful for your exam preparation. So before you take the exam, try this quiz and polish your concepts. If you find the quiz helpful, share it with your friends. All the best!
- 1.
Which of the following is not a step in the formation of endochondral bone?
- A.
Hyaline cartilage develops in to the shape of the future bone
- B.
Periosteum forms from connective tissue on the outside of the developing bone
- C.
Hyaline cartilage changes to adipose tissue
- D.
Osteoblasts deposit osseous tissue in place of the disintegrating cartilage.
Correct Answer
C. Hyaline cartilage changes to adipose tissueExplanation
The formation of endochondral bone involves several steps, including the development of hyaline cartilage in the shape of the future bone, the formation of periosteum from connective tissue on the outside of the developing bone, and the deposition of osseous tissue by osteoblasts in place of the disintegrating cartilage. However, hyaline cartilage changing to adipose tissue is not a step in the formation of endochondral bone.Rate this question:
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- 2.
The hard palate is composed of the
- A.
Sphenoid and ethmoid bones
- B.
Nasal conchae and vomer bones
- C.
Zygomatic and lacrimal bones
- D.
Maxillary and palatine bones
Correct Answer
D. Maxillary and palatine bonesExplanation
The hard palate is the bony structure that forms the roof of the mouth. It is composed of two main bones, the maxillary and palatine bones. The maxillary bone is the largest facial bone and forms the majority of the hard palate. The palatine bone is a smaller bone located towards the back of the hard palate. Together, these bones provide a sturdy and rigid structure for the roof of the mouth, allowing for proper speech and chewing.Rate this question:
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- 3.
The coxal bones include the
- A.
Ilium
- B.
Ischium
- C.
Pubis
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The coxal bones refer to the hip bones in the human body. These bones consist of three parts: the ilium, ischium, and pubis. The ilium is the largest and uppermost part of the coxal bone, forming the prominence of the hip. The ischium is the lower and posterior part of the coxal bone, and it supports the body weight when sitting. The pubis is the anterior part of the coxal bone, which joins with the corresponding bone from the other side at the midline. Therefore, the correct answer is "all of the above" as all three bones mentioned are part of the coxal bones.Rate this question:
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- 4.
Which of the following is a function of the skeletal system?
- A.
Responsible for the production of blood cells
- B.
Storage of inorganic salts
- C.
Protection of organs, especially in the head and thorax
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The skeletal system has multiple functions. It is responsible for the production of blood cells in the bone marrow. It also acts as a storage site for inorganic salts such as calcium and phosphorus. Additionally, the skeletal system provides protection to vital organs, especially in the head and thorax. Therefore, the correct answer is "all of the above" as it encompasses all the mentioned functions of the skeletal system.Rate this question:
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- 5.
Which of the following is an example of the intramembranous bone?
- A.
The parietal bone of the skull
- B.
The phalanges of the fingers
- C.
The humerus of the arm
- D.
The femur of the leg
Correct Answer
A. The parietal bone of the skullExplanation
The parietal bone of the skull is an example of an intramembranous bone. Intramembranous bones are formed directly from mesenchymal cells without the presence of a cartilage precursor. They are typically flat bones found in the skull, such as the parietal bone, and are involved in protecting vital organs. The phalanges of the fingers, humerus of the arm, and femur of the leg are examples of long bones that are formed through endochondral ossification, where a cartilage model is first formed and then replaced by bone tissue.Rate this question:
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- 6.
The presence of a cartilaginous epiphyseal disk indicates that
- A.
The bone length is increasing
- B.
The bone length is no longer increasing
- C.
The bone diameter is increasing
- D.
The bone is dead
Correct Answer
A. The bone length is increasingExplanation
The presence of a cartilaginous epiphyseal disk indicates that the bone length is increasing. The epiphyseal disk is a layer of cartilage located at the ends of long bones, where growth occurs. It allows for the growth and elongation of the bone by the process of ossification. As long as the epiphyseal disk is present, it indicates that the bone is actively growing in length. Once the bone reaches its full length and the epiphyseal disk is replaced by bone tissue, the bone length is no longer increasing.Rate this question:
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- 7.
At what age are all bones normally ossified?
- A.
At birth
- B.
5 years
- C.
15 years
- D.
25 years
Correct Answer
D. 25 yearsExplanation
The process of ossification refers to the formation of bone tissue. At birth, not all bones are fully ossified. As a child grows, the bones continue to ossify and develop. By the age of 25, most individuals have reached skeletal maturity, meaning that all their bones have completed the process of ossification. Therefore, the correct answer is 25 years.Rate this question:
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- 8.
Endochondral ossification involves ___________, whereas intramembranous ossification involves _________.
- A.
Forming bone by replacing hyaline cartilage; replacing connective tissue
- B.
Forming bone in broad, flat area of the skull; the arms and legs
- C.
Hardening of the bone as a result of deposition of calcium salts; osteoclast cells
- D.
Forming bone by the action of the osteocytes; the action of osteoblasts
Correct Answer
A. Forming bone by replacing hyaline cartilage; replacing connective tissueExplanation
Endochondral ossification involves the process of forming bone by replacing hyaline cartilage. This means that during endochondral ossification, the bones develop by replacing a cartilage model. On the other hand, intramembranous ossification involves forming bone by replacing connective tissue. In this process, bone develops directly from mesenchyme or fibrous connective tissue, without the presence of a cartilage model.Rate this question:
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- 9.
Osteoblasts are _________, whereas osteoclasts are _____________.
- A.
Bone forming cells; bone destroying cells
- B.
Mature bone cells ; bone forming cells
- C.
Bone forming cells; mature bone cells
- D.
Bone destroying cells; bone forming cells
Correct Answer
A. Bone forming cells; bone destroying cellsExplanation
Osteoblasts are cells responsible for forming new bone tissue, while osteoclasts are cells responsible for breaking down and resorbing bone tissue. In summary, osteoblasts build bone, and osteoclasts break down bone.Rate this question:
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- 10.
Osteoclast cells are defined as
- A.
Bone cells that secrete bone matrix
- B.
Mature bone cells that maintain the matrix
- C.
Immature bone cells that give rise to osteocytes
- D.
Bone cells that resorb bone tissue
Correct Answer
D. Bone cells that resorb bone tissueExplanation
Osteoclast cells are specialized bone cells that play a crucial role in bone remodeling. Their main function is to resorb or break down bone tissue. They secrete enzymes and acids that dissolve the mineralized matrix of bone, allowing for the release of calcium and other minerals into the bloodstream. This process is essential for maintaining bone homeostasis, repairing damaged bone, and reshaping bone during growth and development. Therefore, the correct answer is "bone cells that resorb bone tissue."Rate this question:
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- 11.
The effects of exercise on bones are to _________ and to __________.
- A.
Thicken ; elongate
- B.
Elongate; weaken
- C.
Thicken ; strengthen
- D.
Thin; atrophy
Correct Answer
C. Thicken ; strengthenExplanation
Exercise has a positive impact on bones by causing them to thicken, which means an increase in bone density. This is because physical activity stimulates the production of new bone tissue, making the bones stronger and less prone to fractures. Additionally, exercise helps to strengthen bones by putting stress on them, which encourages the bones to become denser and more resistant to damage. Therefore, the effects of exercise on bones are to thicken them and to strengthen them.Rate this question:
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- 12.
The proximal ___________ is an expanded portion of the bone that articulates with another bone.
- A.
Cartilage
- B.
Trabeculae
- C.
Epiphysis
- D.
Diaphysis
Correct Answer
C. EpiphysisExplanation
The proximal epiphysis is an expanded portion of the bone that articulates with another bone. This means that it is the part of the bone that forms a joint with another bone, allowing movement and providing stability. The epiphysis is typically located at the ends of long bones and is composed of spongy bone tissue. It contains red bone marrow, which is responsible for producing blood cells.Rate this question:
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- 13.
The white substance that reduces friction, found at the ends of bones is called
- A.
The epiphysis
- B.
Articular cartilage
- C.
The periosteum
- D.
The endosteum
Correct Answer
B. Articular cartilageExplanation
Articular cartilage is the correct answer because it is the white substance that reduces friction found at the ends of bones. It acts as a cushion and allows smooth movement between bones in a joint. The epiphysis refers to the rounded end of a long bone, while the periosteum is the outer layer of bone and the endosteum is the inner layer. However, neither of these substances specifically reduce friction or are found at the ends of bones.Rate this question:
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- 14.
Articular cartilage is made from
- A.
Fibrocartilage
- B.
Endochondral cartilage
- C.
Hyoid cartilage
- D.
Hyaline cartilage
Correct Answer
D. Hyaline cartilageExplanation
Hyaline cartilage is the correct answer because it is the specific type of cartilage that makes up articular cartilage. Articular cartilage is found on the ends of bones in joints and acts as a smooth, slippery surface that allows for easy movement and reduces friction between bones. Hyaline cartilage is characterized by its glassy appearance and is the most common type of cartilage in the body. It is flexible and resilient, making it ideal for cushioning and protecting joints.Rate this question:
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- 15.
Osteoclasts are large cells that cause breakdown of osseous tissue
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
Osteoclasts are indeed large cells that are responsible for the breakdown of osseous tissue. They play a crucial role in bone remodeling and resorption, as they secrete enzymes and acids that dissolve the mineralized matrix of bone. This process allows for the removal of old or damaged bone tissue and the subsequent formation of new bone. Therefore, the statement is true.Rate this question:
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- 16.
The tarsal bones form the wrist
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
The tarsal bones actually form the ankle, not the wrist. The wrist is formed by a group of eight small carpal bones. Therefore, the given statement is false.Rate this question:
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- 17.
The appendicular skeleton consists of parts that support and protect the head, neck and trunk.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
The appendicular skeleton consists of parts that support and protect the limbs, rather than the head, neck, and trunk. The appendicular skeleton includes the bones of the arms, legs, shoulders, and pelvis. These bones provide support and facilitate movement in the limbs, while the axial skeleton, which includes the skull, vertebral column, and ribcage, supports and protects the head, neck, and trunk. Therefore, the statement that the appendicular skeleton consists of parts that support and protect the head, neck, and trunk is false.Rate this question:
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- 18.
Osteocytes become osteoblasts when they are completely surrounded by bony matrix.
- A.
True
- B.
False
Correct Answer
B. FalseExplanation
Osteocytes do not become osteoblasts when completely surrounded by bony matrix. Osteocytes are mature bone cells that are responsible for maintaining and monitoring the bone tissue. Osteoblasts, on the other hand, are responsible for bone formation and are derived from mesenchymal stem cells. While osteocytes can communicate with osteoblasts and influence their activity, they do not transform into osteoblasts themselves. Therefore, the statement is false.Rate this question:
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- 19.
The tough, fibrous tissue that encloses a long bone is called the ________.
- A.
Periosteum
- B.
Ligament
- C.
Stapes
- D.
None of the above
Correct Answer
A. PeriosteumExplanation
The correct answer is Periosteum. The periosteum is a tough, fibrous tissue that covers the outer surface of long bones. It provides protection, nourishment, and support for the bone. It also serves as an attachment point for ligaments and tendons. Ligaments are strong bands of connective tissue that connect bones to other bones, while the stapes is one of the three small bones in the middle ear.Rate this question:
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- 20.
The xyphoid process is part of the _______.
- A.
Sternum
- B.
Trabeculae
- C.
Hyoid
- D.
None of the above
Correct Answer
A. SternumExplanation
The xyphoid process is a small, cartilaginous extension at the lower end of the sternum. It serves as an attachment point for muscles and ligaments in the abdomen, and helps protect the underlying organs. The sternum is a flat bone that runs down the center of the chest and forms the front part of the rib cage. Therefore, the correct answer is sternum.Rate this question:
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- 21.
Osteoblasts are
- A.
Bone forming cells
- B.
Muscle forming cells
- C.
Cartilage forming cells
- D.
None of the above
Correct Answer
A. Bone forming cellsExplanation
Osteoblasts are cells responsible for the formation of bone. They play a crucial role in bone development and remodeling by producing and secreting the proteins and other substances needed to build and mineralize bone tissue. Osteoblasts are derived from mesenchymal stem cells and are responsible for the synthesis and deposition of the bone matrix. They also regulate the activity of osteoclasts, which are responsible for bone resorption. Therefore, the correct answer is "Bone forming cells."Rate this question:
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- 22.
The joints between the bodies of the vertebrae of the backbone are best described as
- A.
Immovable
- B.
Slightly movable
- C.
Freely movable
- D.
Synovial
Correct Answer
B. Slightly movableExplanation
The joints between the bodies of the vertebrae of the backbone are described as slightly movable because while they do allow for a small amount of movement, they are primarily designed to provide stability and support for the spine. These joints, known as cartilaginous joints, are connected by fibrocartilage discs called intervertebral discs, which act as shock absorbers and allow for limited flexion, extension, and rotation of the spine. However, the range of motion in these joints is relatively small compared to freely movable joints found in other parts of the body.Rate this question:
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- 23.
Which of the following is NOT a function of the skeletal system?
- A.
Support and structure
- B.
Protection of internal organs
- C.
Blood cell production
- D.
Hormone regulation
Correct Answer
D. Hormone regulationExplanation
Hormone regulation is primarily the function of the endocrine system, which involves glands that secrete hormones. The skeletal system provides support, protects organs, produces blood cells, and stores minerals.Rate this question:
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- 24.
A suture is an example of a(n)
- A.
Fibrous joint
- B.
Cartilaginous joint
- C.
Synovial joint
- D.
None of the above
Correct Answer
A. Fibrous jointExplanation
A suture is an example of a fibrous joint because it is a type of joint where two bones are held together by fibrous connective tissue. Sutures are found in the skull and are immovable, providing stability and protection to the brain.Rate this question:
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- 25.
Cartilaginous joints are connected by
- A.
Synovial fluid
- B.
Bibrous connective tissue
- C.
Hyaline cartilage or fibrocartilage
- D.
A joint capsule
Correct Answer
C. Hyaline cartilage or fibrocartilageExplanation
Cartilaginous joints are connected by hyaline cartilage or fibrocartilage. These types of joints allow for limited movement and are found in areas such as the spine and the pubic symphysis. Hyaline cartilage is a smooth, flexible connective tissue that covers the ends of bones, allowing them to glide against each other. Fibrocartilage, on the other hand, is a tough, dense connective tissue that acts as a shock absorber and provides stability to the joint. Both hyaline cartilage and fibrocartilage help to cushion the joint and reduce friction during movement.Rate this question:
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- 26.
Bones of a synovial joint are held together by
- A.
A synovial membrane
- B.
A joint capsule
- C.
A meniscus
- D.
A bursa
Correct Answer
B. A joint capsuleExplanation
The correct answer is a joint capsule. A joint capsule is a fibrous structure that surrounds the synovial joint and holds the bones together. It provides stability to the joint and helps prevent dislocation. The joint capsule is composed of an outer fibrous layer and an inner synovial membrane, which produces synovial fluid to lubricate the joint. The synovial membrane helps reduce friction between the bones and allows for smooth movement within the joint. The other options, such as synovial membrane, meniscus, and bursa, also play important roles in the functioning of a synovial joint, but they do not directly hold the bones together like the joint capsule does.Rate this question:
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- 27.
Fluid filled sacs found between the skin and underlying bony prominences are called
- A.
Ligaments
- B.
Menisci
- C.
Bursae
- D.
None of the above
Correct Answer
C. BursaeExplanation
Bursae are fluid-filled sacs that are located between the skin and underlying bony prominences. They serve as cushions to reduce friction and provide protection to the bones, tendons, and muscles. Ligaments are fibrous tissues that connect bones to other bones, while menisci are cartilage structures found in the knee joint. Therefore, the correct answer is bursae.Rate this question:
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- 28.
In which of the following is rotational movement possible?
- A.
Ball and socket
- B.
Condyloid joint
- C.
Hinge joint
- D.
All of the above
Correct Answer
A. Ball and socketExplanation
Rotational movement is possible in a ball and socket joint. This type of joint allows for a wide range of motion in multiple directions, including rotation. The rounded end of one bone fits into the cup-like socket of another bone, allowing for smooth movement and rotation. This type of joint is found in the shoulder and hip, enabling movements such as swinging the arm or rotating the leg. Condyloid joints and hinge joints, on the other hand, do not allow for rotational movement. Condyloid joints allow for movement in two planes, while hinge joints only allow for movement in one plane, like a door hinge.Rate this question:
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- 29.
A muscle end attached to a relatively immovable part is called the
- A.
Symphysis
- B.
Articulation
- C.
Origin
- D.
Insertion
Correct Answer
C. OriginExplanation
The origin of a muscle refers to the point of attachment that is relatively immovable. It is the fixed point from which the muscle begins its contraction. In contrast, the insertion of a muscle is the point of attachment that moves when the muscle contracts. Therefore, the correct answer is "origin" as it correctly describes the muscle end attached to a relatively immovable part.Rate this question:
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- 30.
Which of the following movements could occur at the hip joint?
- A.
Extension
- B.
Rotation
- C.
Adduction
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
All of the listed movements - extension, rotation, and adduction - can occur at the hip joint. Extension refers to the movement of the leg backward, rotation refers to the inward or outward turning of the leg, and adduction refers to the movement of the leg toward the midline of the body. Therefore, all of these movements are possible at the hip joint.Rate this question:
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- 31.
Joints serve to
- A.
Bind skeletal parts together
- B.
Allow bone growth to occur
- C.
Enable body parts to move
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
Joints serve multiple functions in the body. They not only bind skeletal parts together, but also allow bone growth to occur and enable body parts to move. Therefore, the correct answer is "all of the above."Rate this question:
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- 32.
A gomphosis is an example of a(n)
- A.
Fibrous joint
- B.
Cartilaginous joint
- C.
Synovial joint
- D.
Ball and socket
Correct Answer
A. Fibrous jointExplanation
A gomphosis is a type of fibrous joint where a tooth is anchored into its socket in the jawbone by strong connective tissue called periodontal ligaments. This joint provides stability and allows for minimal movement, making it an example of a fibrous joint. Fibrous joints are characterized by the presence of dense fibrous connective tissue between the bones, which limits their range of motion and provides strength and stability to the joint.Rate this question:
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- 33.
Which of the following allows the most possible movements?
- A.
Condyloid joint
- B.
Hinge joint
- C.
Ball and socket
- D.
Pivot joint
Correct Answer
C. Ball and socketExplanation
The ball and socket joint allows the most possible movements because it is a highly mobile joint that allows for flexion, extension, abduction, adduction, rotation, and circumduction. This joint consists of a rounded bone (ball) that fits into a cup-like socket, allowing for a wide range of movements in multiple directions. In contrast, a condyloid joint allows for flexion, extension, abduction, adduction, and circumduction, but not rotation. A hinge joint allows for flexion and extension in one plane, while a pivot joint allows for rotation around a single axis.Rate this question:
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- 34.
Articular cartilage receives oxygen and nutrients from
- A.
A direct blood supply
- B.
Blood vessels in underlying spongy bone
- C.
Surrounding synovial fluid
- D.
Chondrocytes
Correct Answer
C. Surrounding synovial fluidExplanation
Articular cartilage does not have a direct blood supply, so it relies on surrounding synovial fluid for oxygen and nutrients. The synovial fluid, which is present in the joint cavity, contains substances that can diffuse into the cartilage and provide nourishment to the chondrocytes, the cells that make up the cartilage. This mechanism allows for the maintenance and repair of the articular cartilage, which is important for joint function and mobility.Rate this question:
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- 35.
Movements permitted by the elbow are
- A.
Adduction, flexion and extension
- B.
Movement in any plane
- C.
Flexion and extension
- D.
Rotation and circumduction
Correct Answer
C. Flexion and extensionExplanation
The movements permitted by the elbow joint are flexion and extension. Flexion refers to the movement that decreases the angle between the forearm and upper arm, while extension refers to the movement that increases this angle. These two movements allow for the bending and straightening of the arm at the elbow joint. The other options mentioned in the question, such as adduction, rotation, and circumduction, are not possible at the elbow joint.Rate this question:
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- 36.
A joint capsule is reinforced by
- A.
Tendons binding articular ends of bone together
- B.
Articular cartilage cushioning ends of bones
- C.
Ligaments binding articular ends of bones together
- D.
Hyaline cartilage providing strength to the capsule walls
Correct Answer
C. Ligaments binding articular ends of bones togetherExplanation
The joint capsule is a fibrous structure that surrounds a joint and helps to stabilize it. Ligaments are strong bands of connective tissue that connect bones together and provide stability to the joint. They play a crucial role in reinforcing the joint capsule and binding the articular ends of bones together. Tendons, on the other hand, connect muscles to bones and are not directly involved in reinforcing the joint capsule. Articular cartilage and hyaline cartilage are both types of cartilage that provide cushioning and strength to the joint, but they do not specifically bind the articular ends of bones together. Therefore, the correct answer is ligaments binding articular ends of bones together.Rate this question:
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- 37.
Synovial fluid moistens and lubricates the cartilaginous surfaces within a joint
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
Synovial fluid is a lubricating fluid that is found within the joints of the body. Its main function is to reduce friction between the cartilaginous surfaces within the joint, allowing for smooth movement and preventing wear and tear. It also helps to nourish the cartilage and provide it with the necessary nutrients for proper function. Therefore, the statement that synovial fluid moistens and lubricates the cartilaginous surfaces within a joint is true.Rate this question:
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- 38.
The hip joint is a ball and socket joint
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
The hip joint is indeed a ball and socket joint. This means that the rounded head of the femur bone fits into the cup-shaped socket of the pelvis. This type of joint allows for a wide range of motion, including flexion, extension, abduction, adduction, and rotation. The ball and socket joint structure provides stability to the hip joint while also allowing for smooth movement.Rate this question:
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- 39.
The basic structure of the knee joint permits flexion and extension
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
The knee joint is a hinge joint that allows for flexion and extension movements. Flexion refers to bending the knee, while extension refers to straightening it. This is made possible by the basic structure of the knee joint, which includes the femur (thigh bone), tibia (shin bone), and patella (kneecap), as well as ligaments and tendons that provide stability and support.Rate this question:
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- 40.
Straightening the leg at the knee is a type of movement called _______.
- A.
Extension
- B.
Excusrion
- C.
Support
- D.
None of the above
Correct Answer
A. ExtensionExplanation
Straightening the leg at the knee involves increasing the angle between the thigh and the lower leg, which is known as extension. This movement is the opposite of flexion, which is the bending of the leg at the knee. Excursion refers to the movement of a body part away from the midline, support does not describe the specific movement of straightening the leg at the knee, and "none of the above" is not the correct answer as extension accurately describes the movement.Rate this question:
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- 41.
Closed, fluid filled sacs that act as cushions are called _________.
- A.
Bursae
- B.
Flexion
- C.
Sachrine
- D.
None of the above
Correct Answer
A. BursaeExplanation
Bursae are closed, fluid-filled sacs that act as cushions. They are found near joints and help reduce friction between bones, tendons, and muscles during movement. Bursae also provide lubrication, allowing smooth and pain-free motion. Therefore, bursae is the correct answer to the question.Rate this question:
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- 42.
The outermost layer of connective tissue surrounding a skeletal muscle is called the
- A.
Epimysium
- B.
Perimysium
- C.
Endomysium
- D.
Sacromysium
Correct Answer
A. EpimysiumExplanation
The outermost layer of connective tissue surrounding a skeletal muscle is called the epimysium. This layer provides support and protection to the muscle, as well as helps to maintain its shape and integrity. It also connects the muscle to the surrounding structures and allows for proper transmission of forces generated during muscle contraction. The epimysium is made up of dense irregular connective tissue and is continuous with tendons, which attach the muscle to bones.Rate this question:
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- 43.
Myofibrils are primarily composed of
- A.
Actin and myosin
- B.
ATP and ADP
- C.
Troponin
- D.
Tropomyosin
Correct Answer
A. Actin and myosinExplanation
Myofibrils are the contractile units of muscle cells, responsible for muscle contraction. Actin and myosin are the two main proteins found in myofibrils. Actin forms thin filaments, while myosin forms thick filaments. These two proteins work together in a sliding filament mechanism to generate muscle contraction. Therefore, the correct answer is actin and myosin.Rate this question:
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- 44.
The enzyme acetycholinesterase causes acetylcholine to
- A.
Bond to actin
- B.
Be secreted from the motor end plate
- C.
Decompose
- D.
Form cross bridges
Correct Answer
C. DecomposeExplanation
Acetylcholinesterase is an enzyme that breaks down acetylcholine. Acetylcholine is a neurotransmitter that is responsible for transmitting signals in the nervous system. When acetylcholine is no longer needed, acetylcholinesterase breaks it down into its components, effectively decomposing it. This allows for the termination of the signal transmission and the restoration of the normal functioning of the nervous system.Rate this question:
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- 45.
The amount of oxygen needed to support the conversion of lactic acid to glycogen and restore intracellular ATP and creatine phosphate to normal levels, is called the
- A.
Refractory quantity
- B.
Oxygen debt
- C.
Anaerobic concentration
- D.
Aerobic conversion
Correct Answer
B. Oxygen debtExplanation
Oxygen debt refers to the amount of oxygen required to restore normal levels of ATP and creatine phosphate and convert lactic acid to glycogen after intense exercise. During intense exercise, the body relies on anaerobic metabolism, which produces lactic acid as a byproduct. To replenish ATP and creatine phosphate stores and remove lactic acid, the body needs to consume additional oxygen. This additional oxygen consumption even after exercise is over is known as the oxygen debt.Rate this question:
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- 46.
Creatine phosphate serves to
- A.
Cause the decomposition of ATP
- B.
Cause the decomposition of ADP
- C.
Supply energy for the synthesis of ATP
- D.
Supply energy for the change of ATP to ADP
Correct Answer
C. Supply energy for the synthesis of ATPExplanation
Creatine phosphate serves as a source of high-energy phosphate groups that can be transferred to ADP molecules, converting them into ATP. This process is known as phosphorylation and is a crucial step in the synthesis of ATP, the main energy currency in cells. By providing these phosphate groups, creatine phosphate helps replenish ATP levels, ensuring a constant supply of energy for cellular processes.Rate this question:
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- 47.
The all or none response means that
- A.
All of the muscles in a region contract together
- B.
All of the muscle fibers within a muscle contract together
- C.
When a muscle fiber contracts, it contracts completely
- D.
When a muscle fiber contracts, all of its ATP is changed to ADP
Correct Answer
C. When a muscle fiber contracts, it contracts completelyExplanation
The all or none response refers to the fact that when a muscle fiber contracts, it contracts completely. This means that once a muscle fiber receives a stimulus to contract, it will contract fully and with maximum force. There is no partial contraction of a muscle fiber. This principle applies to individual muscle fibers within a muscle, not to all the muscles in a region or all the muscle fibers within a muscle contracting together. Additionally, the conversion of ATP to ADP is a process that occurs during muscle contraction but is not directly related to the all or none response.Rate this question:
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- 48.
Multiunit smooth muscle
- A.
Is composed of sheets of muscle cells
- B.
Tends to display ryhthmicity
- C.
Occurs in the walls of the stomach and intestines
- D.
None of the above
Correct Answer
D. None of the aboveExplanation
The correct answer is "none of the above" because multiunit smooth muscle is not composed of sheets of muscle cells like single-unit smooth muscle. Instead, it consists of individual muscle fibers that are independent and function separately. Additionally, multiunit smooth muscle does not tend to display rhythmicity like single-unit smooth muscle does. Lastly, multiunit smooth muscle is found in structures like the iris of the eye and the walls of blood vessels, not in the stomach and intestines.Rate this question:
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- 49.
Compared to skeltal muscle, smooth muscle
- A.
Contracts more slowly and relaxes more slowly
- B.
Contracts more slowly and relaxes more rapidly
- C.
Contracts more rapidly and relaxes more slowly
- D.
Contracts more rapidly and relaxes more rapidly
Correct Answer
A. Contracts more slowly and relaxes more slowlyExplanation
Smooth muscle is a type of muscle tissue that is found in the walls of internal organs and blood vessels. Compared to skeletal muscle, smooth muscle contracts more slowly and relaxes more slowly. This is because smooth muscle cells have a different structure and organization compared to skeletal muscle cells. Smooth muscle contractions are also typically involuntary and can be sustained for longer periods of time.Rate this question:
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- 50.
The striated appearance of the skeltal muscle results from the
- A.
Transverse tubule pattern
- B.
Sarcoplasmic reticulum network
- C.
Sarcomere arrangement
- D.
Cisternae placement
Correct Answer
C. Sarcomere arrangementExplanation
The correct answer is sarcomere arrangement. The striated appearance of skeletal muscle is due to the arrangement of sarcomeres, which are the basic contractile units of muscle fibers. Sarcomeres are made up of thick and thin filaments that slide past each other during muscle contraction, giving the muscle its striated appearance. The transverse tubule pattern, sarcoplasmic reticulum network, and cisternae placement are all important components of muscle function, but they do not directly contribute to the striated appearance.Rate this question:
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Jan 20, 2025Quiz Edited by
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Jul 30, 2009Quiz Created by
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