BIOL 252 Exam 2 With question and well verified ANSWERs @2026
A tumor has appeared on the hypothalamus of a seven-year-old boy, causing increased secretion of
GHRH. The increase of GHRH has in turn increased GH and IGF levels. If left untreated, the young boy
a. will suffer from acromegaly, in which his bones will increase in girth, especially his head and facial
bones
b. will suffer from gigantism since his epiphyseal plates have not closed.
c. will have a decreased amount of protein synthesis, decreasing muscle development and longitudinal
bone growth
d. will suffer from pituitary dwarfism, where he will be short in stature. - ANSWERS💫✔️-b
A radiograph reveals epiphyseal lines in the long bones of a 12-year-old's hand. Which of the following
statements is correct?
a. The epiphyseal plates have ossified, and further growth in length is not possible
b. Intramembranous ossification will enable continued growth in length
c. Administration of growth hormone will stimulate further bone growth in length
d. More growth will occur during the teenage years as sex hormones stimulate rebuilding of epiphyseal
plates. - ANSWERS💫✔️-a
What stimulates the release of parathyroid hormone (PTH)? - ANSWERS💫✔️-low blood calcium ion
levels
Which of the following is not one of the effects of the parathyroid hormone (PTH)?
a. increased blood calcium concentration
b. increased calcium storage in bones
c. increased calcium reabsorption in the kidneys
d. increased calcium absorption in the small intestine - ANSWERS💫✔️-b --> PTH stimulates osteoclasts
to degrade bone and release calcium.
, Bone, or osseous, tissue provides protection for our vital organs since the inorganic ground substance is:
- ANSWERS💫✔️-calcium phosphate crystals
What accounts for the majority of bone (osseous) tissue matrix? - ANSWERS💫✔️-calcium salts
Osteoblasts are to bone deposition as: - ANSWERS💫✔️-osteoclasts are to bone resorption
T/F: Contractility is the ability of a muscle to shorten - ANSWERS💫✔️-false
If actin filaments were incapable of sliding past the myosin filaments. - ANSWERS💫✔️-Contraction
would not occur, and tension would not be generated
A patient with myasthenia gravis, a disease that destroys acetylcholine receptors at the motor end plate,
will display all the symptoms except:
a. Muscle weakness and partial or full paralysis
b. Muscle hypertrophy
c. Difficulty swallowing
d. Drooping eyelids and double vision - ANSWERS💫✔️-b
Troponin and tropomyosin are regulatory proteins that block the active sites of actin when the muscle is
relaxed, and expose the active sites when the muscle is contracting. If troponin were unable to bind to
tropomyosin...
a. troponin would be able to cover the active sites without the need for tropomyosin
b. tropomyosin would be able to move off the active sites without the need for troponin
c. they would not be able to turn on and off the process of muscle contraction
d. troponin would cover the active sites and tropomyosin would uncover the active sites of actin. -
ANSWERS💫✔️-c
A tumor has appeared on the hypothalamus of a seven-year-old boy, causing increased secretion of
GHRH. The increase of GHRH has in turn increased GH and IGF levels. If left untreated, the young boy
a. will suffer from acromegaly, in which his bones will increase in girth, especially his head and facial
bones
b. will suffer from gigantism since his epiphyseal plates have not closed.
c. will have a decreased amount of protein synthesis, decreasing muscle development and longitudinal
bone growth
d. will suffer from pituitary dwarfism, where he will be short in stature. - ANSWERS💫✔️-b
A radiograph reveals epiphyseal lines in the long bones of a 12-year-old's hand. Which of the following
statements is correct?
a. The epiphyseal plates have ossified, and further growth in length is not possible
b. Intramembranous ossification will enable continued growth in length
c. Administration of growth hormone will stimulate further bone growth in length
d. More growth will occur during the teenage years as sex hormones stimulate rebuilding of epiphyseal
plates. - ANSWERS💫✔️-a
What stimulates the release of parathyroid hormone (PTH)? - ANSWERS💫✔️-low blood calcium ion
levels
Which of the following is not one of the effects of the parathyroid hormone (PTH)?
a. increased blood calcium concentration
b. increased calcium storage in bones
c. increased calcium reabsorption in the kidneys
d. increased calcium absorption in the small intestine - ANSWERS💫✔️-b --> PTH stimulates osteoclasts
to degrade bone and release calcium.
, Bone, or osseous, tissue provides protection for our vital organs since the inorganic ground substance is:
- ANSWERS💫✔️-calcium phosphate crystals
What accounts for the majority of bone (osseous) tissue matrix? - ANSWERS💫✔️-calcium salts
Osteoblasts are to bone deposition as: - ANSWERS💫✔️-osteoclasts are to bone resorption
T/F: Contractility is the ability of a muscle to shorten - ANSWERS💫✔️-false
If actin filaments were incapable of sliding past the myosin filaments. - ANSWERS💫✔️-Contraction
would not occur, and tension would not be generated
A patient with myasthenia gravis, a disease that destroys acetylcholine receptors at the motor end plate,
will display all the symptoms except:
a. Muscle weakness and partial or full paralysis
b. Muscle hypertrophy
c. Difficulty swallowing
d. Drooping eyelids and double vision - ANSWERS💫✔️-b
Troponin and tropomyosin are regulatory proteins that block the active sites of actin when the muscle is
relaxed, and expose the active sites when the muscle is contracting. If troponin were unable to bind to
tropomyosin...
a. troponin would be able to cover the active sites without the need for tropomyosin
b. tropomyosin would be able to move off the active sites without the need for troponin
c. they would not be able to turn on and off the process of muscle contraction
d. troponin would cover the active sites and tropomyosin would uncover the active sites of actin. -
ANSWERS💫✔️-c
