Ch. 6 Bone Tissue and the Skeletal System Flashcards
Which function of the skeletal system would be especially important if you were in a car accident?
A) Storage of minerals.
B) Protection of internal organs.
C) Facilitation of movement.
D) Fat storage.
B) Protection of internal organs.
Explanation: In a car accident, bones like the ribs, skull, and spine help shield vital organs from trauma.
Incorrect:
A) Storage of minerals: Important but not related to injury prevention.
C) Facilitation of movement: Disrupted in accidents but not protective.
D) Fat storage: Related to energy, not injury response.
Bone tissue can be described as (BLANK).
A) Dead calcified tissue.
B) Cartilage.
C) The skeletal system.
D) Dense, hard connective tissue.
D) Dense, hard connective tissue.
Explanation: Bone is a living, mineralized connective tissue made strong by its matrix and cells.
Incorrect:
A) Dead calcified tissue: Bones are alive, not dead.
B) Cartilage: A different type of connective tissue.
C) The skeletal system: A broader term that includes bones and cartilage.
Without red marrow, bones would not be able to (BLANK).
A) Store phosphate.
B) Store calcium.
C) Make blood cells.
D) Move like levers.
C) Make blood cells.
Explanation: Red marrow is the site of hematopoiesis (blood cell production).
Incorrect:
A) Store phosphate: Managed by the bone matrix.
B) Store calcium: Also handled by the matrix.
D) Move like levers: A mechanical function, not related to red marrow.
Yellow marrow has been identified as (BLANK).
A) An area of fat storage.
B) A point of attachment for muscles.
C) The hard portion of bone.
D) The cause of kyphosis.
A) An area of fat storage.
Explanation: Yellow marrow stores adipose tissue, serving as an energy reserve.
Incorrect:
B) A point of attachment for muscles: This is the periosteum or bone surface.
C) The hard portion of bone: Refers to compact bone.
D) The cause of kyphosis: A spinal deformity, unrelated to marrow.
Which of the following can be found in areas of movement?
A) Hematopoiesis.
B) Cartilage.
C) Yellow marrow.
D) Red marrow.
B) Cartilage.
Explanation: Cartilage cushions joints and reduces friction in areas of movement.
Incorrect:
A) Hematopoiesis: Occurs in red marrow, not linked to movement.
C) Yellow marrow: Located inside bone, not associated with joints.
D) Red marrow: Also internal to bone, not found in areas of movement.
The skeletal system is made of (BLANK).
A) muscles and tendons.
B) Bones and cartilage.
C) Vitreous humor.
D) Minerals and fat.
B) Bones and cartilage.
Explanation: These are the main structural components of the skeletal system.
Incorrect
A) Muscles and tendons: Belong to the muscular system.
C) Vitreous humor: Part of the eye.
D) Minerals and fat: Stored in bone but not structural parts of the skeletal system.
Most of the bones of the arms and hands are long bones; however, the bones in the wrist are categorized as (BLANK).
A) Flat bones.
B) Short bones.
C) Sesamoid bones.
D) Irregular bones.
B) Short bones.
Explanation: Carpals in the wrist are cube-like and classified as short bones.
Incorrect:
A) Flat bones: These protect organs like the skull and ribs.
C) Sesamoid bones: These are embedded in tendons, such as the patella.
D) Irregular bones: These have complex shapes, like the vertebrae.
Sesamoid bones are found embedded in (BLANK).
A) Joints.
B) Muscles.
C) Ligaments.
D) Tendons.
D) Tendons.
Explanation: Sesamoid bones reduce stress in tendons and improve movement.
Incorrect
A) Joints: Not where sesamoid bones are located.
B) Muscles: Sesamoid bones are not embedded in muscles.
C) Ligaments: These connect bones but don’t contain sesamoid bones.
Bones that surround the spinal cord are classified as (BLANK) bones.
A) Irregular.
B) Sesamoid.
C) Flat.
D) Short.
A) Irregular.
Explanation: Vertebrae have complex shapes and protect the spinal cord, classifying them as irregular bones.
Incorrect
B) Sesamoid: These are found in tendons, not the spine.
C) Flat: Flat bones are found in the skull and ribcage.
D) Short: Short bones are in the wrists and ankles.
Which category of bone is among the most numerous in the skeleton?
A) Long bone.
B) Sesamoid bone.
C) Short bone.
D) Flat bone.
A) Long bone.
Explanation: Long bones (arms, legs, fingers, toes) are the most common in the skeleton.
Incorrect
B) Sesamoid bone: These are variable and relatively few.
C) Short bone: Only found in certain areas like the wrists and ankles.
D) Flat bone: Fewer in number, found in places like the skull and ribs.
Long bones enable body movement by acting as a (BLANK).
A) Counterweight.
B) Resistive force.
C) Lever.
D) Fulcrum.
C) Lever.
Explanation: Long bones act as levers that muscles pull on to create movement.
Incorrect
A) Counterweight: Not an anatomical function of bones. B) Resistive force: More of a physics or muscular concept, not specific to bone structure. D) Fulcrum: Joints, not bones, act as the fulcrum.
Which of the following occurs in the spongy bone of the epiphysis?
A) bone growth.
B) bone remodeling.
C) hematopoiesis.
D) shock absorption.
C) hematopoiesis.
Explanation: Red marrow in spongy bone of the epiphyses is the site of blood cell production.
Incorrect
A) Bone growth: Occurs at the epiphyseal plate.
B) Bone remodeling: Happens throughout the bone, not specific to epiphysis.
D) Shock absorption: Handled more by cartilage and synovial fluid.
The diaphysis contains (BLANK).
A) the metaphysis.
B) fat stores.
C) spongy bone.
D) compact bone.
B) Fat stores.
Explanation: The medullary cavity within the diaphysis stores yellow marrow (fat).
Incorrect
A) Metaphysis: Located between diaphysis and epiphysis.
C) Spongy bone: Found primarily in epiphyses.
D) Compact bone: Forms the outer layer but not the cavity contents.
The fibrous membrane covering the outer surface of the bone is the (BLANK).
A) periosteum.
B) epiphysis.
C) endosteum.
D) diaphysis.
A) periosteum.
Explanation: The periosteum is a fibrous membrane covering the outer surface of bones.
Incorrect
B) Epiphysis: End part of long bones, not a membrane.
C) Endosteum: Lines the inner surface of the bone cavity.
D) Diaphysis: The shaft of a long bone.
Which of the following are incapable of undergoing mitosis?
A) osteoblasts and osteoclasts.
B) osteocytes and osteoclasts.
C) osteoblasts and osteocytes.
D) osteogenic cells and osteoclasts.
B) osteocytes and osteoclasts.
Explanation: These are mature cells that no longer divide.
A) Osteoblasts: Can divide when active.
C) Osteocytes: Do not divide, but osteoblasts can.
D) Osteogenic cells: Stem cells that actively divide; osteoclasts do not.
Which cells do not originate from osteogenic cells?
A) osteoblasts.
B) osteoclasts.
C) osteocytes.
D) osteoprogenitor cells.
B) osteoclasts.
Explanation: Osteoclasts come from monocyte/macrophage lineage, not osteogenic cells.
Incorrect
A), C), and D): All come from the osteogenic lineage.
Which of the following are found in compact bone and cancellous bone?
A) Haversian systems.
B) Haversian canals.
C) Lamellae.
D) Lacunae.
D) Lacunae.
Explanation: Lacunae are spaces housing osteocytes, present in both bone types.
Incorrect
A) Haversian systems: Only in compact bone.
B) Haversian canals: Found in compact bone.
C) Lamellae: Found in both but organized into osteons only in compact bone.
Which of the following are only found in cancellous bone?
A) Canaliculi.
B) Volkmann’s canals.
C) Trabeculae.
D) Calcium salts.
C) Trabeculae.
Explanation: Trabeculae form the lattice of cancellous (spongy) bone.
Incorrect
A) Canaliculi: Present in both bone types.
B) Volkmann’s canals: Found in compact bone.
D) Calcium salts: Found in all bone types.
The area of a bone where the nutrient foramen passes forms what kind of bone marking?
A) Hole.
B) Facet.
C) Canal.
D) Fissure.
A) Hole.
Explanation: A foramen is a hole through which vessels and nerves pass.
Incorrect
B) Facet: A smooth, flat surface for articulation.
C) Canal: A long tunnel-like opening.
D) Fissure: A narrow slit-like opening.
Why is cartilage slow to heal?
A. Because it eventually develops into bone.
B. Because it is semi-solid and flexible.
C. Because it does not have a blood supply.
D. Because endochondral ossification replaces all cartilage with bone.
C. Because it does not have a blood supply.
Explanation: Cartilage is avascular, meaning it lacks blood vessels, which limits nutrient delivery and slows healing.
Incorrect
A) Eventually develops into bone: Only true during specific developmental stages, not related to healing.
B) Semi-solid and flexible: Describes structure, not healing.
D) Endochondral ossification: Related to development, not injury repair.
Why are osteocytes spread out in bone tissue?
A. They develop from mesenchymal cells.
B. They are surrounded by osteoid.
C. They travel through the capillaries.
D. Formation of osteoid spreads out the osteoblasts that formed the ossification centers.
D. Formation of osteoid spreads out the osteoblasts that formed the ossification centers.
Explanation: As osteoid is secreted, osteoblasts are spaced apart and become osteocytes within lacunae.
A) Mesenchymal cells: Precursor stage, not the cause of spacing.
B) Surrounded by osteoid: True, but doesn’t explain spacing.
C) Travel through capillaries: Osteocytes are stationary, not mobile.
In endochondral ossification, what happens to the chondrocytes?
A. They develop into osteocytes.
B. They die in the calcified matrix that surrounds them and form the medullary cavity.
C. They grow and form the periosteum.
D. They group together to form the primary ossification center.
B. They die in the calcified matrix that surrounds them and form the medullary cavity.
Explanation: Chondrocytes die when the cartilage calcifies, creating space for the medullary cavity.
Incorrect
A) Develop into osteocytes: Incorrect—these are different cell lineages.
C) Form the periosteum: This forms from perichondrium, not chondrocytes.
D) Form ossification center: Osteoblasts, not chondrocytes, do this.
Which of the following bones is (are) formed by intramembranous ossification?
A. The metatarsals.
B. The femur.
C. The ribs.
D. The flat bones of the cranium.
D. The flat bones of the cranium.
Explanation: These bones develop directly from mesenchymal tissue without a cartilage intermediate.
Incorrect
A), B), and C): These all form through endochondral ossification.
Bones grow in length due to activity in the (BLANK).
A. Epiphyseal plate.
B. Perichondrium.
C. Periosteum.
D. Medullary cavity.
A. Epiphyseal plate.
Explanation: This growth plate contains actively dividing cartilage cells that lengthen the bone.
Incorrect
B) Perichondrium and C) Periosteum: Involved in appositional (diameter) growth.
D) Medullary cavity: Involved in fat storage, not growth.
Bones grow in diameter due to bone formation (BLANK).
A. In the medullary cavity.
B. Beneath the periosteum.
C. In the epiphyseal plate.
D. Within the metaphysis.
B. Beneath the periosteum.
Explanation: Osteoblasts add new bone beneath the periosteum, causing the bone to grow outward.
Incorrect
A) Medullary cavity: Remodeling happens here, not growth.
C) Epiphyseal plate: Responsible for length, not diameter.
D) Metaphysis: Transition zone, not a site of diameter growth.
A fracture can be both (BLANK).
A. open and closed.
B. open and transverse.
C. transverse and greenstick.
D. greenstick and comminuted.
B. Open and transverse.
Explanation: A fracture can be described both by direction (e.g., transverse) and whether the skin is broken (e.g., open)
Incorrect:
A) Open and closed: These are opposite classifications.
C) Transverse and greenstick: One is a full break, the other is partial, typically in children.
D) Greenstick and comminuted: Greenstick is a simple crack; comminuted is shattered—very different injury types.
How can a fractured diaphysis release fat globules into the bloodstream?
A. The bone pierces fat stores in the skin.
B. The yellow marrow in the diaphysis is exposed and damaged.
C. The injury triggers the body to release fat from healthy bones.
D. The red marrow in the fractured bone releases fat to heal the fracture.
B. The yellow marrow in the diaphysis is exposed and damaged.
Explanation: Trauma to yellow marrow (which stores fat) in the diaphysis can lead to fat embolism.
Incorrect:
A) Fat stores in the skin are unrelated to marrow.
C) Fat release from other bones isn’t trauma-induced.
D) Red marrow doesn’t store or release fat.
In a compound fracture, (BLANK).
A. The break occurs at an angle to the bone.
B. The broken bone does not tear the skin.
C. One fragment of broken bone is compressed into the other.
D. Broken bone pierces the skin.
D. Broken bone pierces the skin.
Explanation: A compound fracture, also called an open fracture, breaks through the skin, increasing the risk of infection.
Incorrect:
A) An angled break describes an oblique fracture.
B) No skin break describes a closed fracture.
C) Bone fragments pushed together describe an impacted fracture.
The internal and external calli are replaced by (BLANK).
A. Hyaline cartilage.
B. Trabecular bone.
C. Osteogenic cells.
D. Osteoclasts.
B. Trabecular bone.
Explanation: Soft calli are replaced with spongy (trabecular) bone during the healing process.
Incorrect
A) Hyaline cartilage forms earlier but is later replaced.
C) Osteogenic cells aid healing but don’t replace the calli.
D) Osteoclasts break down damaged bone but don’t form new bone tissue.
The first type of bone to form during fracture repair is (BLANK) bone.
A. Compact.
B. Lamellar.
C. Spongy.
D. Dense.
C. Spongy.
Explanation: Spongy (trabecular) bone forms first as the callus ossifies.
Incorrect
A) Compact and D) Dense: These form later during remodeling.
B) Lamellar: This is mature bone structure that appears after spongy bone is reorganized.
Wolff’s law, which describes the effect of mechanical forces in bone modeling/remodeling, would predict that (BLANK).
A. A right-handed pitcher will have thicker bones in his right arm compared to his left.
B. A right-handed cyclist will have thicker bones in her right leg compared to her left.
C. A broken bone will heal thicker than it was before the fracture.
D. A bed-ridden patient will have thicker bones than an athlete.
A. A right-handed pitcher will have thicker bones in his right arm compared to his left.
Explanation: Wolff’s law states that bones adapt to mechanical stress by becoming denser and stronger with use.
Incorrect
B) Right-legged cyclist: Both legs are used equally.
C) Broken bone healing thicker: May happen temporarily but not consistently.
D) Bed-ridden patient: Would lose bone mass due to lack of mechanical stress.
Calcium cannot be absorbed from the small intestine if (BLANK) is lacking.
A. Vitamin D.
B. Vitamin K.
C. Calcitonin.
D. Fluoride.
A. Vitamin D.
Explanation: Vitamin D (calcitriol) facilitates active calcium absorption in the small intestine.
Incorrect
B) Vitamin K: Important for bone mineralization but not absorption.
C) Calcitonin: Regulates calcium deposition, not absorption.
D) Fluoride: Strengthens enamel, not relevant to calcium uptake.
Which one of the following foods is best for bone health?
A. Carrots.
B. Liver.
C. Leafy green vegetables.
D. Oranges.
C. Leafy green vegetables.
Explanation: Leafy greens are rich in calcium, magnesium, and vitamin K—all vital for bone strength.
Incorrect
A) Carrots: High in vitamin A, not strongly linked to bone health.
B) Liver: High in vitamin A and iron, but not key for bone formation.
D) Oranges: Provide vitamin C for collagen, but less directly impactful than leafy greens.
Which of the following hormones are responsible for the adolescent growth spurt?
A. Estrogen and testosterone.
B. Calcitonin and calcitriol.
C. Growth hormone and parathyroid hormone.
D. Thyroxine and progesterone.
A. Estrogen and testosterone.
Explanation: These sex hormones cause the rapid growth during adolescence and initiate growth plate closure.
Incorrect
B) Calcitonin and calcitriol: Involved in calcium regulation, not growth acceleration.
C) Growth hormone helps but PTH is unrelated to growth spurts.
D) Thyroxine and progesterone: Related to metabolism and reproduction, not bone growth.
With respect to their direct effects on osseous tissue, which pair of hormones has actions that oppose each other?
A. Estrogen and testosterone.
B. Calcitonin and calcitriol.
C. Estrogen and progesterone.
D. Calcitonin and parathyroid hormone.
D. Calcitonin and parathyroid hormone.
Explanation: PTH raises blood calcium by activating osteoclasts; calcitonin lowers it by inhibiting them.
A) Estrogen and testosterone: Both promote bone formation.
B) Calcitonin and calcitriol: Work in tandem for calcium regulation.
C) Estrogen and progesterone: Have different roles but not direct opposition in bone metabolism.
When calcium levels are too high or too low, which body system is primarily affected?
A. Skeletal system.
B. Endocrine system.
C. Digestive system.
D. Nervous system.
D. Nervous system.
Explanation: Calcium is essential for proper nerve impulse transmission; imbalances can disrupt neural signaling.
Incorrect
A) Skeletal system: Major calcium store but not the first to show functional symptoms.
B) Endocrine system: Regulates calcium but is not the primary system affected by imbalance.
C) Digestive system: Absorbs calcium, not disrupted by calcium levels.
All of the following play a role in calcium homeostasis except:
A. Thyroxine.
B. Calcitonin.
C. Parathyroid hormone.
D. Vitamin D.
A. Thyroxine.
Explanation: Thyroxine influences metabolism and bone growth, not calcium regulation.
Incorrect
B) Calcitonin: Lowers blood calcium.
C) Parathyroid hormone: Raises blood calcium.
D) Vitamin D: Enhances calcium absorption.
Which of the following is most likely to be released when blood calcium levels are elevated?
A. Thyroxine.
B. Calcitonin.
C. Parathyroid hormone.
D. Vitamin D.
B. Calcitonin.
Explanation: Calcitonin is secreted by the thyroid when calcium is high to inhibit osteoclasts and lower calcium levels.
Incorrect
A) Thyroxine: Not involved in calcium balance.
C) Parathyroid hormone: Released when calcium is low.
D) Vitamin D: Promotes calcium absorption but does not directly reduce calcium levels.
