GRCC BI 121 Lecture Exam 2 (Corfixen) Questions
with verified answers
Ball and Socket Ans✓✓✓ shoulder and hip
Comminuted Fracture Ans✓✓✓ fracture in which the bone is
splintered or crushed/breaks into many fragments, most likely in the
hands and feet
Compund Fracture Ans✓✓✓ When a bonebreaks into more than two
pieces and possibly punctures the skin
Condyloid Ans✓✓✓ wrist and knuckles
Define the term oxygen debt. Ans✓✓✓ The amount of extra oxygen
needed to react with the lactic acid and remove it from the cells.
Describe the development of an intramembranous bone Ans✓✓✓
Intramembranous bones begin as membrane-like layers of embryonic
connective tissue (mesenchyme). Cells in the connective tissue
differentiate into osteoblasts that deposit bony matrix around
themselves. Spongy bone forms along the blood vessels within the
connective tissue. Connective tissue that persists on the outside of the
developing bone gives rise to the periosteum. Osteoblasts beneath the
periosteum form a layer of compact bone over the surface of the
spongy bone.
, Describe the events leading to muscle fiber contraction. Begin at the
neuromuscular junction and end at the actin sliding over myosin
Ans✓✓✓ 1. Motor neuron sends action potential (nerve impulse) to
the muscle
2. acetylcholine (ACh) release from vesicles on motor neuron
3. ACh binds to receptors on muscle membrane & activates 2nd action
potential, now on muscle
4. Action potential opens active transport pumps of sarcoplasmic
reticulum
5. Ca+2 floods sarcoplasm, AChE degrades ACh
6. Ca+2 attaches to troponin of TT complex and changes its shape
7. This shape change pulls tropomyosin away from myosin-binding sites
on actin
8. ATP attaches to ATP binding site on myosin crossbridge
9. ATP use on myosin head in presence of Mg+ splits ATP into ADP+P
which energizes myosin head (swings forward)
10. P flies off and myosin head binds to binding site on actin
11. ADP is pushed off + myosin head is de-energized (pulling actin
forward) non myosin swivels back to resting state
12. Repeat 8-11 until the Ca+2 comes off the TT complex
Describe the joint disorders Ans✓✓✓ Osteoarthritis - occurs when
flexible tissue at the ends of bones wears down
with verified answers
Ball and Socket Ans✓✓✓ shoulder and hip
Comminuted Fracture Ans✓✓✓ fracture in which the bone is
splintered or crushed/breaks into many fragments, most likely in the
hands and feet
Compund Fracture Ans✓✓✓ When a bonebreaks into more than two
pieces and possibly punctures the skin
Condyloid Ans✓✓✓ wrist and knuckles
Define the term oxygen debt. Ans✓✓✓ The amount of extra oxygen
needed to react with the lactic acid and remove it from the cells.
Describe the development of an intramembranous bone Ans✓✓✓
Intramembranous bones begin as membrane-like layers of embryonic
connective tissue (mesenchyme). Cells in the connective tissue
differentiate into osteoblasts that deposit bony matrix around
themselves. Spongy bone forms along the blood vessels within the
connective tissue. Connective tissue that persists on the outside of the
developing bone gives rise to the periosteum. Osteoblasts beneath the
periosteum form a layer of compact bone over the surface of the
spongy bone.
, Describe the events leading to muscle fiber contraction. Begin at the
neuromuscular junction and end at the actin sliding over myosin
Ans✓✓✓ 1. Motor neuron sends action potential (nerve impulse) to
the muscle
2. acetylcholine (ACh) release from vesicles on motor neuron
3. ACh binds to receptors on muscle membrane & activates 2nd action
potential, now on muscle
4. Action potential opens active transport pumps of sarcoplasmic
reticulum
5. Ca+2 floods sarcoplasm, AChE degrades ACh
6. Ca+2 attaches to troponin of TT complex and changes its shape
7. This shape change pulls tropomyosin away from myosin-binding sites
on actin
8. ATP attaches to ATP binding site on myosin crossbridge
9. ATP use on myosin head in presence of Mg+ splits ATP into ADP+P
which energizes myosin head (swings forward)
10. P flies off and myosin head binds to binding site on actin
11. ADP is pushed off + myosin head is de-energized (pulling actin
forward) non myosin swivels back to resting state
12. Repeat 8-11 until the Ca+2 comes off the TT complex
Describe the joint disorders Ans✓✓✓ Osteoarthritis - occurs when
flexible tissue at the ends of bones wears down
