Question

explain the excretory system of man
​

Answer 1

Explanation:

1. Structure of kidney

Excretory system in human consists of a pair of kidneys, a pair of ureters, urinary bladder and urethra (Figure. 8.2). Kidneys are reddish brown, bean shaped structures that lie in the superior lumbar region between the levels of the last thoracic and third lumber vertebra close to the dorsal inner wall of the abdominal cavity. The right kidney is placed slightly lower than the left kidney. Each kidney weighs an average of 120-170 grams. The outer layer of the kidney is covered by three layers ofsupportive tissues namely, renal fascia, perirenal fat capsule and fibrous capsule

2. Structure of a nephron

Each kidney has nearly one million complex tubular structures called nephron (Figure 8.4). Each nephron consists of a filtering corpuscle called renal corpuscle (malpighian body) and a renal tubule. The renal tubule opens into a longer tubule called the collecting duct. The renal tubule beginswith a double walled cup shaped structure called the Bowman’s capsule, which encloses a ball of capillaries that delivers fluid to the tubules, called the glomerulus (Figure 8.4). The Bowman’s capsule and the glomerulus together constitute the renal corpuscle. The endothelium of glomerulus has many pores (fenestrae).

The renal tubule continues further to form the proximal convoluted tubule [PCT] followed by a U-shaped loop of Henle (Henle’s loop) that has a thin descending and a thick ascending limb. The ascending limb continues as a highly coiled tubular region called the distal convoluted tubule [DCT]. The DCT of many nephrons open into a straight tube called collecting duct. The collecting duct runs through the medullary pyramids in the region of the pelvis. Several collecting ducts fuse to form papillary duct that delivers urine into the calyces, which opens into the renal pelvis.

The capillary bed of the nephrons-First capillary bed of the nephron is the glomerulus and the other is the peritubular capillaries. The glomerular capillary bed is different from other capillary beds in that it is supplied by the afferent and drained by the efferent arteriole.

This is your answer.....

Answer 2

Answer:

The excretory system is the system of an organism's body that performs the function of excretion, the bodily process of discharging wastes.

Explanation:

The Excretory system is responsible for the elimination of wastes produced by homeostasis. There are several parts of the body that are involved in this process, such as sweat glands, the liver, the lungs and the kidney system, From there, urine is expelled through the urethra and out of the body.