Category: Biology Second Paper Lecture Sheet

Kidney-function, importance

1. Blood Purification: As a result of metabolism, nitrogenous waste products – urea, uric acid, creatinine etc. are created in the human body. These waste materials are excreted from the body through the kidneys. As a result blood is purified.
2. Acid-base balance: Kidneys regulate the levels of mineral salts and bicarbonate in the body. It regulates the acid-base balance in the blood.
3. Water balance: Kidneys regulate water balance in the body through osmoregulation.
4. Temperature regulation: It regulates temperature throughout the body.
5. Vitamin production: Kidneys produce vitamin D in the body.
6. Blood cell production: Erythropoietin hormone is produced in kidney. Erythropoietin makes red blood cells in the body.
7. Blood pressure regulation: Kidneys regulate blood pressure in the body with the help of various hormones.
8. Hormone production: Kidney produces hormones like erythropoietin, prostaglandin, angiotensin, calcitriol etc. in the animal body.
9. Removal of toxins: It removes toxins from the body.
10. Mineral salts: Kidney controls the amount of sodium, potassium, calcium, phosphate, chloride etc. in the human body.
11. Gluconeogenesis: In the process of gluconeogenesis, sugar is produced from proteins and lipids. Gluconeogenesis occurs during prolonged starvation. During this time the kidney can supply about 20% glucose.
12. Enzyme secretion: Renin enzyme is secreted from kidney. Renin acts like an enzyme hormone.
13. Regulation of Osmosis: Kidneys regulate the osmotic pressure between blood and cells-tissues in the body.
14. Bone and teeth formation: Kidney plays a major role in vitamin-D production. Vitamin-D regulates calcium levels in the blood. Calcium forms bones and teeth.
15. Homeostasis: Homeostasis is the internal orderly environment of the body. Kidneys maintain homeostasis in the body by removing waste products from the blood.

Kidney-Medulla

The central part of kidney wall is called medulla. It is light red in color. It consists of 8-18 pyramidal structures. It is called renal pyramid. The base of the pyramid faces the cortex and the apex faces the renal sinus. The top of the pyramid is called Papilla. Papilla with 10-25 pores. Apex of papilla opens into minor calyx. The minor calyxes open together into the major calyx. Also, the pillar-like part of the cortex between the two renal pyramids is called the Renal column. (iii) Pelvis: The large collecting space inside the kidney is called the pelvic floor. There are two types of branchial parts in the pelvis. There are 2-3 main branches. Major branches are called major calyxes. 8-14 minor calyxes arise from the major calyx.

Kidney-Cortex

The outermost layer of kidney wall is called cortex. It is divided into two parts. Supercial cortex and juxtamedullary cortex. The outer layer of the cortex is called the superficial cortex and the inner layer of the cortex is called the juxtamedullary cortex. The supracial cortex contains 85% and the juxtamedullary cortex 15% of nephrons. The cortex contains the renal corpuscle, proximal convoluted tubule, and distal convoluted tubule of the nephron.

Kidney-Cortex

The outermost layer of kidney wall is called cortex. It is divided into two parts. Supercial cortex and juxtamedullary cortex. The outer layer of the cortex is called the superficial cortex and the inner layer of the cortex is called the juxtamedullary cortex. The supracial cortex contains 85% and the juxtamedullary cortex 15% of nephrons. The cortex contains the renal corpuscle, proximal convoluted tubule, and distal convoluted tubule of the nephron.

Kidney-Internal anatomy, Structure

Three regions are seen in the longitudinal section of the kidney. These are-
(i) Cortex : The outermost layer of kidney wall is called cortex. It is divided into two parts. Supercial cortex and juxtamedullary cortex. The outer layer of the cortex is called the superficial cortex and the inner layer of the cortex is called the juxtamedullary cortex. The supracial cortex contains 85% and the juxtamedullary cortex 15% of nephrons. The cortex contains the renal corpuscle, proximal convoluted tubule, and distal convoluted tubule of the nephron.
(ii) Medulla: The central part of kidney wall is called medulla. It is light red in color. It consists of 8-18 pyramidal structures. It is called renal pyramid. The base of the pyramid faces the cortex and the apex faces the renal sinus. The top of the pyramid is called Papilla. Papilla with 10-25 pores. Apex of papilla opens into minor calyx. The minor calyxes open together into the major calyx. Also, the pillar-like part of the cortex between the two renal pyramids is called the Renal column. (iii) Pelvis: The large collecting space inside the kidney is called the pelvic floor. There are two types of branchial parts in the pelvis. There are 2-3 main branches. Major branches are called major calyxes. 8-14 minor calyxes arise from the major calyx.

Kidney-External anatomy, Structure

Kidneys look like bean seeds and are reddish-brown in color. Its length is 10-12 cm, width is 5-6 cm and thickness is 3 cm. Male kidney weighs 125-170 grams and female kidney weighs 115-155 grams. Its outer side is convex and inner side is concave. The fold in the concave part is called Hilus. The hilus is attached to the ureter. Each kidney is covered by a fibrous connective tissue called the renal capsule or tunica fibrosa. Outside the renal capsule is a fatty layer that protects the kidney from friction. At the tip of the kidney are the cap-like adrenal glands.

Kidney-Anatomy, structure of Kidney

Kidney is the main excretory organ of human body. This is called a body filter. In 1842, Sir William Bowman first explained the exact structure of the kidney. The structure of kidney can be described in two ways. External structure and internalization.
1. External Structure
Kidneys look like bean seeds and are reddish-brown in color. Its length is 10-12 cm, width is 5-6 cm and thickness is 3 cm. Male kidney weighs 125-170 grams and female kidney weighs 115-155 grams. Its outer side is convex and inner side is concave. The fold in the concave part is called Hilus. The hilus is attached to the ureter. Each kidney is covered by a fibrous connective tissue called the renal capsule or tunica fibrosa. Outside the renal capsule is a fatty layer that protects the kidney from friction. At the tip of the kidney are the cap-like adrenal glands.
2. Internal Structure
Three regions are seen in the longitudinal section of the kidney. These are-
(i) Cortex : The outermost layer of kidney wall is called cortex. It is divided into two parts. Supercial cortex and juxtamedullary cortex. The outer layer of the cortex is called the superficial cortex and the inner layer of the cortex is called the juxtamedullary cortex. The supracial cortex contains 85% and the juxtamedullary cortex 15% of nephrons. The cortex contains the renal corpuscle, proximal convoluted tubule, and distal convoluted tubule of the nephron.
(ii) Medulla: The central part of kidney wall is called medulla. It is light red in color. It consists of 8-18 pyramidal structures. It is called renal pyramid. The base of the pyramid faces the cortex and the apex faces the renal sinus. The top of the pyramid is called Papilla. Papilla with 10-25 pores. Apex of papilla opens into minor calyx. The minor calyxes open together into the major calyx. Also, the pillar-like part of the cortex between the two renal pyramids is called the Renal column. (iii) Pelvis: The large collecting space inside the kidney is called the pelvic floor. There are two types of branchial parts in the pelvis. There are 2-3 main branches. Major branches are called major calyxes. 8-14 minor calyxes arise from the major calyx.