Flashcards For NEET Biology - Locomotion and Movement

Many fascicles held together by fascia (collagenous connective tissue) to form a skeletal muscle

Part of a myofibril between two consecutive ‘Z’ lines

Made up of:- ‘F’-actin, which is a polymer of ‘G’ (globular) actin, Tropomyosin and Troponin, which masks the active binding sites of myosin

Monomeric unit- Meromyosins

Heavy meromyosin (HMM)- globular head and short arm

Light meromyosin (LMM)- tail

The binding site for calcium ions and actin filament

The length remains the same during contraction

The length reduces during muscle contraction

Occurs due to repeated activation and low oxygen availability

Myoglobin content is high

Large amount of mitochondria are present

Myoglobin content is low

Fewer mitochondria but more sarcoplasmic reticulum

Frontal, parietal (2), temporal (2), occipital, sphenoid, ethmoid

A pair of lacrimal, nasal, zygomatic, maxillae, palatine, nasal conchae and one vomer and mandible (lower jaw, movable)

Cervical- 7

Thoracic- 12

Lumber- 5

Sacral- 1 (fused)

Coccygeal- 1 (fused)

True ribs- 1^st to 7^th

Vertebrochondral or false ribs- 8^th to 10^th

Floating ribs- 11^th and 12^th

Humerus, radius, ulna, carpals (8, wrist bones), metacarpals (5, palm), phalanges (14, digits)

Femur (longest bone), tibia, fibula, patella (knee cap), tarsals (7, ankle bones), metatarsals (5, sole), phalanges (14, digits)

Head of the humerus articulates with the glenoid cavity, forming shoulder joint

Head of the femur articulates with acetabulum cavity

Bones are joined by dense fibrous connective tissues

E.g. skull bones in the cranium

Bones are joined by cartilage

E.g. vertebrae in the vertebral column

Synovial cavity between articulating surfaces of two bones

E.g. Pivot joint- between atlas and axis

Saddle joint- between carpal and metacarpal of the thumb

Gliding joint- between the carpals, Ball and socket, Hinge joint, etc.

Antibodies destroy or block the acetylcholine receptors

Progressive weakness and degeneration of skeletal muscles

Continued contractions leading to rapid spasms

Also known as lockjaw, painful muscle spasms

Decreased bone mass

Low estrogen level is a common cause

Accumulation of uric acid crystals in joints causing inflammation