Rigor mortis is the third stage of death characterized by stiffening of joints and muscles in body. The stiffening occurs because muscles are not able to return to the relaxed state. There are two reasons for rigor mortis, depletion of ATP and increase in calcium concentration in cytosol. Due to these factors the actin-myosin crossbridge is not able to break and the muscles remain in contracted state.

Sarcoplasmic reticulum deteriorates and calcium is released into the cytosol. Sarcolemma ( covering of muscle fiber ) also breaks down releasing extra calcium into the cytosol. Calcium is responsible for formation of actin-myosin cross bridge and when its concentration increases the bridge is formed continuously leading to stiffening of muscles and joints.

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2 years ago

The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin

Korolek [52]

The vitamin that plays an important roles in the epithelia and in the synthesis of visual pigments is vitamin A.

Vitamin A (retinol) is needed for the synthesis of photopigments. The photopigment rhodopsin is synthesized withinside the rods and is answerable for imaginative and prescient beneathneath low ranges of light. When nutritional reassets of diet A are insufficient for a protracted length of time, the quantity of visible pigment withinside the photoreceptors declines.

Vitamin A (VitA) is a micronutrient this is important for preserving imaginative and prescient, selling boom and development, and defensive epithelium and mucus integrity withinside the body.Vitamin A is critical for lots physiological processes, which includes preserving the integrity and feature of all floor tissues (epithelia): for example, the skin, the liner of the respiration tract, the gut, the bladder, the internal ear and the eye.

Describe the eardrums function￼.

Describe the eardrums function.