ANP 650 FINAL EXAM
LATEST ACTUAL EXAM
1. Question: Describe the process of bone remodeling and the cells
involved.
Answer: Bone remodeling is a continuous process of bone resorption and formation that
ensures bone strength and mineral homeostasis. The process involves:
● Osteoclasts: Multinucleated cells responsible for bone resorption. They break down old
bone tissue by releasing acids and enzymes.
● Osteoblasts: These are bone-forming cells that secrete the bone matrix. After laying
down new bone, some osteoblasts become embedded and differentiate into osteocytes.
● Osteocytes: Mature bone cells derived from osteoblasts. They help maintain the bone
matrix and communicate with other bone cells to regulate the remodeling process.
2. Question: What is the role of parathyroid hormone (PTH) in calcium
homeostasis?
Answer: PTH is crucial for regulating blood calcium levels:
● It increases calcium resorption from the bones by stimulating osteoclast activity.
● PTH enhances reabsorption of calcium in the kidneys, reducing urinary calcium
excretion.
● It also increases the activation of vitamin D, which enhances calcium absorption in the
intestines.
3. Question: Explain the differences between compact bone and spongy
bone.
Answer:
● Compact bone: Dense and forms the outer layer of bones. It is organized into osteons
or Haversian systems, which consist of concentric layers of bone matrix and central
canals containing blood vessels and nerves.
● Spongy bone: Less dense and found mainly at the ends of long bones and within the
interior of other bones. It is composed of a network of trabeculae, which contain bone
marrow and are oriented to withstand stress.
,4. Question: What factors influence bone growth and development?
Answer: Several factors influence bone growth and development, including:
● Hormones: Growth hormone, sex hormones (estrogen and testosterone), and thyroid
hormone play key roles.
● Nutritional Factors: Adequate intake of calcium, phosphorus, and vitamin D is essential
for bone mineralization.
● Mechanical Stress: Physical activity stimulates bone growth through mechanical stress,
which increases bone density and strength via remodeling.
5. Question: Describe the difference between primary and secondary
osteoporosis.
Answer:
● Primary osteoporosis: Commonly age-related, particularly affecting postmenopausal
women due to decreased estrogen levels or elderly individuals due to reduced bone
formation.
● Secondary osteoporosis: Occurs as a result of an underlying condition (e.g.,
hyperparathyroidism, chronic corticosteroid use, or malabsorption syndromes).
:
6. Question: What are the stages of fracture healing?
Answer: Fracture healing occurs in several stages:
1. Hematoma Formation: Blood vessels are torn at the site of injury, leading to a
hematoma, which forms a clot.
2. Fibrocartilaginous Callus Formation: Fibroblasts and chondroblasts form a soft callus
made of collagen and cartilage, bridging the broken bone ends.
3. Bony Callus Formation: Osteoblasts replace the fibrocartilaginous callus with a bony
(hard) callus made of spongy bone.
4. Bone Remodeling: The bone callus is remodeled to form compact bone, restoring the
bone's original shape and strength.
7. Question: Explain the structure of a typical synovial joint.
Answer: A typical synovial joint has:
● Joint Capsule: A fibrous connective tissue capsule that encloses the joint cavity.
● Synovial Membrane: Lines the inner surface of the capsule and produces synovial fluid.
● Synovial Fluid: Lubricates the joint and reduces friction between articular surfaces.
● Articular Cartilage: Covers the ends of the bones in the joint, providing a smooth
surface to reduce friction.
● Ligaments: Connect bone to bone and stabilize the joint.
● Menisci or Articular Discs (in some joints): Fibrocartilage pads that improve fit
between articulating bones.
, 8. Question: What are the three types of muscle tissue, and what are their
characteristics?
Answer:
● Skeletal Muscle: Striated, voluntary muscle that is attached to bones and causes
movement by contracting.
● Cardiac Muscle: Striated, involuntary muscle found in the heart; features intercalated
discs that allow rapid signal transmission.
● Smooth Muscle: Non-striated, involuntary muscle found in the walls of internal organs
and blood vessels; controls movement such as peristalsis.
9. Question: Describe the sliding filament theory of muscle contraction.
Answer: The sliding filament theory states that during muscle contraction:
● Actin (thin) filaments slide over myosin (thick) filaments, shortening the sarcomere
and thus the muscle.
● Calcium ions released from the sarcoplasmic reticulum bind to troponin, causing
tropomyosin to move and expose binding sites on actin.
● Myosin heads attach to the actin filaments, forming cross-bridges, then pull the actin
toward the center of the sarcomere in a "power stroke."
● ATP is required to detach myosin heads and re-cock them for another cycle of
contraction.
10. Question: What is the difference between isotonic and isometric muscle
contractions?
Answer:
● Isotonic Contraction: Muscle length changes to produce movement, such as lifting a
weight. It can be concentric (muscle shortens) or eccentric (muscle lengthens).
● Isometric Contraction: Muscle length does not change; tension increases without
movement, such as holding a heavy object in a fixed position.
11. Question: What are the primary differences between slow-twitch and
fast-twitch muscle fibers?
Answer:
● Slow-twitch (Type I): Red fibers adapted for endurance; rely on aerobic metabolism,
have more mitochondria and myoglobin, and are fatigue-resistant.
● Fast-twitch (Type II): White fibers adapted for power and speed; rely on anaerobic
metabolism, fatigue quickly, and are used in explosive movements.
12. Question: What are the main functions of the autonomic nervous
system (ANS)?
Answer: The ANS controls involuntary bodily functions and consists of two divisions:
LATEST ACTUAL EXAM
1. Question: Describe the process of bone remodeling and the cells
involved.
Answer: Bone remodeling is a continuous process of bone resorption and formation that
ensures bone strength and mineral homeostasis. The process involves:
● Osteoclasts: Multinucleated cells responsible for bone resorption. They break down old
bone tissue by releasing acids and enzymes.
● Osteoblasts: These are bone-forming cells that secrete the bone matrix. After laying
down new bone, some osteoblasts become embedded and differentiate into osteocytes.
● Osteocytes: Mature bone cells derived from osteoblasts. They help maintain the bone
matrix and communicate with other bone cells to regulate the remodeling process.
2. Question: What is the role of parathyroid hormone (PTH) in calcium
homeostasis?
Answer: PTH is crucial for regulating blood calcium levels:
● It increases calcium resorption from the bones by stimulating osteoclast activity.
● PTH enhances reabsorption of calcium in the kidneys, reducing urinary calcium
excretion.
● It also increases the activation of vitamin D, which enhances calcium absorption in the
intestines.
3. Question: Explain the differences between compact bone and spongy
bone.
Answer:
● Compact bone: Dense and forms the outer layer of bones. It is organized into osteons
or Haversian systems, which consist of concentric layers of bone matrix and central
canals containing blood vessels and nerves.
● Spongy bone: Less dense and found mainly at the ends of long bones and within the
interior of other bones. It is composed of a network of trabeculae, which contain bone
marrow and are oriented to withstand stress.
,4. Question: What factors influence bone growth and development?
Answer: Several factors influence bone growth and development, including:
● Hormones: Growth hormone, sex hormones (estrogen and testosterone), and thyroid
hormone play key roles.
● Nutritional Factors: Adequate intake of calcium, phosphorus, and vitamin D is essential
for bone mineralization.
● Mechanical Stress: Physical activity stimulates bone growth through mechanical stress,
which increases bone density and strength via remodeling.
5. Question: Describe the difference between primary and secondary
osteoporosis.
Answer:
● Primary osteoporosis: Commonly age-related, particularly affecting postmenopausal
women due to decreased estrogen levels or elderly individuals due to reduced bone
formation.
● Secondary osteoporosis: Occurs as a result of an underlying condition (e.g.,
hyperparathyroidism, chronic corticosteroid use, or malabsorption syndromes).
:
6. Question: What are the stages of fracture healing?
Answer: Fracture healing occurs in several stages:
1. Hematoma Formation: Blood vessels are torn at the site of injury, leading to a
hematoma, which forms a clot.
2. Fibrocartilaginous Callus Formation: Fibroblasts and chondroblasts form a soft callus
made of collagen and cartilage, bridging the broken bone ends.
3. Bony Callus Formation: Osteoblasts replace the fibrocartilaginous callus with a bony
(hard) callus made of spongy bone.
4. Bone Remodeling: The bone callus is remodeled to form compact bone, restoring the
bone's original shape and strength.
7. Question: Explain the structure of a typical synovial joint.
Answer: A typical synovial joint has:
● Joint Capsule: A fibrous connective tissue capsule that encloses the joint cavity.
● Synovial Membrane: Lines the inner surface of the capsule and produces synovial fluid.
● Synovial Fluid: Lubricates the joint and reduces friction between articular surfaces.
● Articular Cartilage: Covers the ends of the bones in the joint, providing a smooth
surface to reduce friction.
● Ligaments: Connect bone to bone and stabilize the joint.
● Menisci or Articular Discs (in some joints): Fibrocartilage pads that improve fit
between articulating bones.
, 8. Question: What are the three types of muscle tissue, and what are their
characteristics?
Answer:
● Skeletal Muscle: Striated, voluntary muscle that is attached to bones and causes
movement by contracting.
● Cardiac Muscle: Striated, involuntary muscle found in the heart; features intercalated
discs that allow rapid signal transmission.
● Smooth Muscle: Non-striated, involuntary muscle found in the walls of internal organs
and blood vessels; controls movement such as peristalsis.
9. Question: Describe the sliding filament theory of muscle contraction.
Answer: The sliding filament theory states that during muscle contraction:
● Actin (thin) filaments slide over myosin (thick) filaments, shortening the sarcomere
and thus the muscle.
● Calcium ions released from the sarcoplasmic reticulum bind to troponin, causing
tropomyosin to move and expose binding sites on actin.
● Myosin heads attach to the actin filaments, forming cross-bridges, then pull the actin
toward the center of the sarcomere in a "power stroke."
● ATP is required to detach myosin heads and re-cock them for another cycle of
contraction.
10. Question: What is the difference between isotonic and isometric muscle
contractions?
Answer:
● Isotonic Contraction: Muscle length changes to produce movement, such as lifting a
weight. It can be concentric (muscle shortens) or eccentric (muscle lengthens).
● Isometric Contraction: Muscle length does not change; tension increases without
movement, such as holding a heavy object in a fixed position.
11. Question: What are the primary differences between slow-twitch and
fast-twitch muscle fibers?
Answer:
● Slow-twitch (Type I): Red fibers adapted for endurance; rely on aerobic metabolism,
have more mitochondria and myoglobin, and are fatigue-resistant.
● Fast-twitch (Type II): White fibers adapted for power and speed; rely on anaerobic
metabolism, fatigue quickly, and are used in explosive movements.
12. Question: What are the main functions of the autonomic nervous
system (ANS)?
Answer: The ANS controls involuntary bodily functions and consists of two divisions:
