Ultrafiltration is the process by which small molecules like water, glucose, mineral ions, and urea are filtered out of the blood and into the Bowman's capsule to form glomerular filtrate.

A high hydrostatic pressure is formed within the glomerulus because the diameter of the afferent arteriole is greater than that of the efferent arteriole.

The high hydrostatic pressure in the glomerulus helps to squeeze water, glucose, and mineral ions out of the capillary to form the glomerular filtrate.

The endothelial cells have pores between them that allow water, glucose, and mineral ions to be squeezed out of the capillary to form the glomerular filtrate.

The basement membrane acts as a selective barrier, allowing most plasma contents to pass through from the blood but preventing the passage of blood cells and large molecules like proteins.

The collagen fibres act as a selective filter preventing large molecules and blood cells from passing into the Bowman's capsule.

Podocytes are specialised cells in the inner layer of the Bowman's capsule that help filter the blood.

They have extensions known as pedicels that wrap around capillaries and prevent cells and large molecules from entering the nephron.

The glomerular filtration rate is the volume of blood that is filtered through the kidneys in a given time.