Chapter 6 Flashcards
True or False: The three types of cartilage are hyaline, elastic, and fibroblastic.
A) True
B) False
B) False
Explanation: The three types of cartilage are hyaline, elastic, and fibrocartilage.
True or False: Osteomalacia is a condition where bones are poorly mineralized, leading to soft and weak bones.
A) True
B) False
A) True
Explanation: Osteomalacia is characterized by inadequate mineralization of bones, resulting in soft and weak bone structure.
What type of bone growth increases the length of long bones?
A) Appositional growth
B) Endochondral growth
C) Intramembranous growth
D) Interstitial growth
D) Interstitial growth
Explanation: Interstitial growth is responsible for the increase in the length of long bones, occurring at the epiphyseal plate.
Match the hormone with its function in the skeletal system:
A. Growth hormone
B. Thyroid hormone
C. Testosterone/Estrogen
D. Parathyroid hormone
- Stimulates osteoclasts to degrade bone matrix releasing Ca2+
- Most important hormone in stimulating epiphyseal plate activity in infancy and childhood
- Modulates activity of growth hormone and ensures proper proportions
- Promotes adolescent growth spurts and causes masculinization or feminization of the skeleton; later ends longitudinal bone growth by inducing epiphyseal plate closure
2, 3, 4, 1
Explanation: Growth hormone stimulates epiphyseal plate activity, thyroid hormone modulates growth hormone, testosterone/estrogen promote growth spurts and epiphyseal plate closure, and parathyroid hormone regulates calcium levels by stimulating osteoclast activity.
Which component contributes to the tensile strength and flexibility of bones?
A) Hydroxyapatites
B) Collagen fibers
C) Calcium phosphate
D) Osteocytes
B) Collagen fibers
Explanation: Collagen fibers, part of the organic matrix called osteoid, provide tensile strength and flexibility to bones.
True or False: Cartilage has a flexible matrix that can accommodate mitosis of chondrocytes, making it an excellent scaffolding tissue upon which to build bone.
A) True
B) False
A) True
Explanation: Cartilage’s flexible matrix allows for the mitosis of chondrocytes, which is essential for bone growth and development.
Which of the following is NOT a classification of bones by shape?
A) Long bones
B) Flat bones
C) Regular bones
D) Short bones
C) Regular bones
Explanation: Bones are classified by shape into long, flat, short, and irregular bones. There is no category called “regular bones.”
True or False: Bone lengthening ceases when the epiphyseal plate closes.
A) True
B) False
A) True
Explanation: Bone lengthening stops when the epiphyseal plate closes, which happens near the end of adolescence.
True or False: The periosteum is involved in bone growth and repair.
A) True
B) False
A) True
Explanation: The periosteum contains osteogenic cells that can differentiate into bone-forming cells, thus playing a key role in bone growth and repair.
Fill in the blank: The __________ contains osteogenic cells that can differentiate into osteoblasts and contribute to bone growth and repair.
Periosteum
Explanation: The periosteum is a dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints.
Fill in the blank: The two control loops that regulate bone remodeling are __________ and __________.
Ca2+ homeostasis and responses to mechanical/gravitational forces
Explanation: Bone remodeling is regulated by the balance of calcium levels in the blood (Ca2+ homeostasis) and the mechanical and gravitational forces acting on the bones, ensuring that bone strength and integrity are maintained.
True or False: Cartilage is converted into bone during endochondral ossification.
A) True
B) False
B) False
Explanation: During endochondral ossification, cartilage is not converted into bone but is replaced by bone.
True or False: Cartilage is highly vascularized and innervated.
A) True
B) False
B) False
Explanation: Cartilage is avascular and does not contain nerves; it is surrounded by the perichondrium, which provides nutrients.
Fill in the blank: Bone development or ossification begins in the ________ month of embryonic development.
Second
Explanation: Ossification, or the process of bone formation, begins in the second month of embryonic development.
Fill in the blank: In adults, ________ bone is replaced approximately every 3-4 years, while ________ bone is replaced approximately every 10 years.
Spongy, compact
Explanation: Spongy bone is replaced every 3-4 years, and compact bone is replaced every 10 years in adults.
What is the role of red bone marrow in adults?
A) Mineral storage
B) Blood cell formation
C) Fat storage
D) Bone remodeling
B) Blood cell formation (hematopoiesis)
Explanation: In adults, red bone marrow is responsible for hematopoiesis, the process of forming new blood cells. It is typically found within the trabeculae of spongy bone, particularly in flat bones like the sternum and pelvic bones.
Which cells are responsible for bone resorption?
A) Osteoblasts
B) Osteocytes
C) Osteoclasts
D) Chondrocytes
C) Osteoclasts
Explanation: Osteoclasts are the cells that break down bone tissue during bone resorption.
What is the function of osteoblasts in bone tissue?
A) Break down bone
B) Form bone matrix
C) Store fat
D) Provide nutrients
B) Form bone matrix
Explanation: Osteoblasts are bone-forming cells that secrete the bone matrix, which includes collagen and calcium-binding proteins.
True or False: Skeletal cartilage contains blood vessels and nerves.
A) True
B) False
B) False
Explanation: Skeletal cartilage does not contain blood vessels or nerves. It is surrounded by a layer of dense irregular connective tissue called the perichondrium, which contains blood vessels for nutrient delivery.
True or False: The periosteum is involved in bone growth and repair.
A) True
B) False
A) True
Explanation: The periosteum contains osteogenic cells that can differentiate into bone-forming cells, thus playing a key role in bone growth and repair.
Fill in the blank: The most abundant type of cartilage in the human body is __________ cartilage.
Hyaline
Explanation: Hyaline cartilage is the most abundant type of cartilage in the human body.
True or False: The periosteum is a double-layered membrane that covers the external surfaces of bones.
A) True
B) False
A) True
Explanation: The periosteum is a double-layered membrane that covers the outer surfaces of bones except at the joint surfaces, providing protection and serving as an attachment point for tendons and ligaments.
Fill in the blank: Fibrocartilage is found in the __________, __________, and __________.
Intervertebral discs, pubic symphysis, menisci of the knee
Explanation: Fibrocartilage is found in areas that require strong support and the ability to withstand heavy pressure.
Which type of cartilage is found in the intervertebral discs and the meniscus of the knee?
A) Hyaline cartilage
B) Elastic cartilage
C) Fibrocartilage
D) Articular cartilage
C) Fibrocartilage
Explanation: Fibrocartilage is found in the intervertebral discs and the meniscus of the knee, where it provides strong support and the ability to withstand heavy pressure.
True or False: Spongy bone contains osteons.
A) True
B) False
B) False
Explanation: Spongy bone does not contain osteons. Instead, it has trabeculae, which align along lines of stress to help resist it.
True or False: Compact bone is also known as lamellar bone due to its lamellae structure.
A) True
B) False
A) True
Explanation: Compact bone is referred to as lamellar bone because it is composed of lamellae, which are layers of bone matrix arranged in concentric circles.