(MSCDFSM)

Q2. Give the functions/role of the following structure/organs in our today:

(i) Bundle of His

(ii) Pineal gland

(iii) Glucagon

(iv) Retina Nerve Cells – Cones

(v) Bone Marrow

ANS(I)-The bundle of His is an important part of the electrical conduction system of the heart, as it transmits impulses from the atrioventricular node, located at the inferior end of the interatrial septum, to the ventricles of the heart. ... These fibers distribute the impulse to the ventricular muscle.

(II)- How you think and feel every day depends on the pineal gland. As the producer of the hormone melatonin, the quality and duration of your sleep relies on how well it produces this hormone. This tiny organ regulates your daily and seasonal circadian rhythms, the sleep-wake patterns that determine your hormone levels, stress levels, and physical performance.

(III)- Blood sugar levels are an important part of overall health. When blood sugar levels drop, an individual may feel lethargic. If they drop too low, the individual may become disoriented, dizzy or even pass out. Blood sugar control involves a complex system of hormones, and one of those hormones is glucagon.

(IV)- The retina contains two types of photoreceptors, rods and cones. The rods are more numerous, some 120 million, and are more sensitive than the cones. However, they are not sensitive to color. The 6 to 7 million cones provide the eye's color sensitivity and they are much more concentrated in the central yellow spot known as the macula. In the center of that region is the " fovea centralis ", a 0.3 mm diameter rod-free area with very thin, densely packed cones.

(V)- Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains stem cells. The stem cells can develop into the red blood cells that carry oxygen through your body, the white blood cells that fight infections, and the platelets that help with blood clotting.