Question

Which of the following nerves function to control the muscles of the eye? CN III (oculomotor), V (trigeminal), and VI (abducens) CN III (oculomotor), V (trigeminal), and VII (facial) CN III (oculomotor), VI (abducens), and VII (facial) CN III (oculomotor), IV (trochlear), and VI (abducens)

Answer 1

1)

CN III (Occulomotor) , IV (trochlear) , V ( abducens )

• There are three cranial nerve which carry signal from the brain to control extraocular muscles of eye.
• Occulomotor nerve - which control majority of muscles .
• Trochlear nerve - which control superior oblique muscle.
• Abducens nerve - Control lateral rectus muscle.
• Option A and B are wrong because trigeminal nerve help in transmitting sensory information from skin , sinuses and mucous membrane in the face .
• Option C is wrong because , facial nerve control muscles of facial expression.

2)

Contains high level of collagen and elastin.

Has a proteoglycan rich in extra cellular matrix.

• Fibroblast is a biological tissue which synthesize an extracellular matrix and collagen , which play structural framework for  tissues and critical role in wound healing.
• It is most commonly seen in cells of connective tissue of an animal.
• Proteoglycan is produced by fibroblast , which help in retention of water.
• They are found rich in extracellular matrix .Hence both option are correct.
• Option B is wrong because fibroblast doesnot play a role in insulation and energy storage.
• Option D is wrong , because regeneration of its population is not quick.

3)

Trigeminal CN V

• Trigeminal cranial nerve is the largest cranial nerve , which have both sensory and motor division.
• It innervates the muscles of mastication , which help in chewing of food.Hence damage to this nerve cause disability in chewing food.
• Option A is wrong because Glossopharyngeal nerve is wrong because it is innervating posterio 1/3 rd of cranial nerve.
• Option B is wrong because Facial nerve help in controlling muscles of facial expression.
• Option D is wrong because , acessory nerve is help in controling the sternocleidomastoid and trapezius muscles.

4)

Transverse ; ( superior / inferior)

• Shoulder joint is an example of multiplanar / triaxial joint.
• Internal and external rotation of shoulder joint occur in transverse plane. Hence option A and B is wrong ( it doesnot occur in sagittal and frontal plane )
• in vertical axis that is superior / inferior.Hence option C is wrong ( it is not medial / lateral axis)
• Both the rotation have ROM (range of motion )of 90 degree.
• Muscles involved in internal rotation include , subscapularis , teres major , pectoralis major

5)

Desmosomes

• Desmosomes are intracellular jucnction  , in which two adjacent cells are strongly attached formed from protein plaques in the cell membranes .
• They also link intracellularly to the intermediate filament cytoskeleton they form adhesive bonds in a network which give strong mechanical strength to tissues.
• Option B is wrong because hemidesmosome are small stud like structure , which are present in keratinocytes of epidermis of skin which attach tho the extracellular matrix.
• Option C is wrong because gap junction connect between cytoplasm of two cells.
• Option D is wrong because tight junction help in preventing leakage of transported solutes and water.