RBSE Class 11 Biology Notes Chapter 19 Excretory Products and their Elimination

These comprehensive RBSE Class 11 Biology Notes Chapter 19 Excretory Products and their Elimination will give a brief overview of all the concepts.

Rajasthan Board RBSE Solutions for Class 11 Biology in Hindi Medium & English Medium are part of RBSE Solutions for Class 11. Students can also read RBSE Class 11 Biology Important Questions for exam preparation. Students can also go through RBSE Class 11 Biology Notes to understand and remember the concepts easily.

RBSE Class 11 Biology Chapter 19 Notes Excretory Products and their Elimination

→ Excretion in the elimination of waste products (especially nitrogen containing products produced during metabolism) from the body of an organism.

→ Waste products are unwanted toxic byproducts which are removed to maintain homeostasis and protect the body from their toxicity.

→ Nitrogenous waste products excreted by animals are mostly ammonia, urea, uric acid, amino acid creatinine etc.

→ Depending upon the major nitrogen excretory products, animals are aminotelic, ammonotelic, ureotelic and uricotelic.

→ Kidneys are the primary or major excretory organs of vertebrates.

RBSE Class 11 Biology Notes Chapter 19 Excretory Products and their Elimination 

→ Urine is the primary or major excretory product,

→ Liver also perform a major function in excretory system by forming urea from ammonia released during deamination of amino acids.

→ Green glands are the excretory organs of crustaceans.

→ Renette cells are the excretory organs of nematodes.

→ Nephron is the structural and functional unit of kidney which has two portions-glomerulus and renal tubules.

→ Glomerulus is a tuft of capillaries formed from afferent arterioles, fine branches of renal artery.

→ The renal tubule starts with Bowriian’s capsule and is further differentiated into a PCT, Henle’s loop (H.L.).

→ The DCT of many nephrons joins to a common collecting duct many of which ultimately open into the renal pelvis through the medullary pyramids.

→ Urine formation involves three main processes i.e., ultrafiltration, reabsorption and secretion.

→ Filtration is a non-selective process performed by the glomerulus using the glomerular capillary blood pressure.

→ About 1200 mL of blood is filtered by the glomerulus per minute to form 121 mL filtrate in the Bowman’s capsule/minute (GFP),

→ JGA, a specialised portion of nephron plays a significant role in the regulation of GFR.

→ PCT is the major site of reabsorption and selective secretion.

→ DCT and collecting ducts allows extensive reabsorption of water and certain electrolytes which helps in osmoregulation.

→ A counter current mechanism operates between the two limbs of Henle’s loop and those of vasa recta.

→ DCT and collecting ducts concentrate the filtrate about four times i.e., from 300 m osm/L to 1200 m osm/L.

RBSE Class 11 Biology Notes Chapter 19 Excretory Products and their Elimination

→ Urine is stored in urinary bladder till a voluntary signal from CNS carries out it releases through urethra (micturition).

→ Skin, lungs and liver also play the role in excretion.

→ Excretion: The process of removal of excretory wastes from the body.

→ Osmoregulation: Maintenance of Osmotic concentration inside the body despite the change in external surrounding.

→ Homeostasis Maintenance of equilibrium between the organism and external environment.

→ Ammonotelic: The animals which excrete ammonia are called ammonotelic.

→ Aminotelic: The animals which excrete amino acid are called aminotelic animals.

→ Ureotelic: The animals which excrete urea are called ureotelic animals.

→ Uricotelic: The animals which excrete uric acid called uricotelic animals.

→ Flame cells: These are excretory organs of platyhelminthes.

→ Nephridia: These are the excretory organs of annelids.

→ Renette cells: Excretory organs of nematoda.

→ Green glands (Antennat glands): Excretory organs of crustaceans.

→ Nephron: Structural and functional unit of kidney.

→ Cortical Nephron: Small nephrons of which major part lies in the cortex.

→ Juxta Medullary Nehpron: Large sized nephrons of which major part lies in the medulla.

→ Bowman's Capsule: It is blind double walled cup shaped structure of nephron.

→ Glomerulus: The tuft of capillaries in the Bowman’s capsule.

→ Malpighian body: The glomerulus, connective tissues and Bowman’s capsule together called Malpighian body or Malpighian capsule or renal capsule.

→ Henle's loop: ‘U’ shaped part of nephron which has descending and ascending limbs.

→ Glomerular filtration rate (GFR): The rate of filtration of blood by glomerulus is called GFR.

→ Juxtaglomerular apparatus: It is a special sensitive region formed by cellular modifications in the distal convoluted tubules and the afferent arteriole at the location of their contact.

→ Micturition: The action of urinating.

→ Micturition reflax: The neural mechanism causing micturition is called micturition reflax.

RBSE Class 11 Biology Notes Chapter 19 Excretory Products and their Elimination

→ Urochrome: A pigment which impart a specific colour to urine.

→ Uremia: Presence of excess amount of urea in the blood.

→ Diabetes Mellitus: Excess of sugar level (glucose) in blood.

→ Diabetes insipidus: A condition of intense thirst and heavy urination.

→ Protemiria: Excess of protein level in urine.

→ Albuminuria: Presence of albumin in urine.

→ Ketonuria: Presence of ketone bodies in urine.

→ Haematurea: Presnece of blood or blood cells in urine.

→ Diuresis: Rate of passing out of urine becomes high due to very dilute urine.

→ Haemoglobinourea: Presnece of haemoglobin in urine.

Prasanna
Last Updated on July 8, 2022, 10:23 a.m.
Published July 8, 2022