Tag: Excretion

Introduction to Excretion

Introduction to Excretion Excretion is the process by which metabolic waste is removed from the body of an organism. Essentially, metabolic waste can be defined as a harmful product of the metabolic activities taking place in the cell of an organism. The unwanted metabolic waste is called excreta and they are removed by the excretory…...

Excretory Products

Excretory Products Carbon Dioxide This is a by-product of respiration of both plants and animals. If it is allowed to accumulate in the cells and associated tissue fluid; the pH will be lowered. Since enzymes are pH sensitive, the Carbon dioxide must be removed. Carbon dioxide is excreted through the pores of the stomata in…...

Excretion in Plants

Excretion in Plants Excretion occurs in plants and animals as they both have waste products to be removed from their bodies. Plants are less complex in structure than animals, and have their own means of excretion. Plants eliminate some waste through diffusion. During the day, excess oxygen gas produced by photosynthesis is released through the…...

The Kidneys

The Kidneys Functions of the kidney The two main functions of the kidney are: – Removal of metabolic waste (excretion) – Osmoregulation, which involves regulating water and salt concentration in the blood. Structure of the kidney There is one pair of kidneys located in the abdominal cavity in the region of the lower back. They…...

Structure and Function of the Nephron

Structure and Function of the Nephron The nephron is a long tube that runs from the cortex into the medulla and back again to the cortex before joining another tube called the collecting duct. The nephron starts as a small cup-like structure known as the Bowman’s capsule and leads into what is known as the…...

Production of Urine

Production of Urine The blood from the afferent arteriole, which enters the Bowman’s capsule, is rich in nutrients such as glucose, fatty acids, amino acids, vitamins, proteins, urea and excess salts. The membranes of the glomerulus and Bowman’s capsule are permeable to small molecules and ions, such as water, urea and salts, but are not…...

Osmoregulation

Osmoregulation This is the regulation of the amount of water present in the human body. The human body is approximately 70% water, as such, a certain level of water must be maintained. If the body fluids become too diluted, water will enter cells by osmosis causing them to swell or even burst. If the body…...