EXCRETION in HUMANS

FLASHCARDS

Define the term excretion.

Excretion is the removal from the body of the waste products of metabolism, and any substances present in excess, e.g. excess salts

Which waste products of metabolism are excreted by the lungs?

The metabolic waste products excreted by the lungs are water and carbon dioxide, both produced during respiration.

True or False?

The kidneys excrete urea, excess water and carbon dioxide.

False.

The kidneys excrete urea, excess water and ions.

Carbon dioxide is excreted via the lungs.

What are the structures labelled A-D in the diagram?

Diagram of the human urinary system with labeled parts: A (kidneys), B (the tube that connects the kidneys and the bladder), C (bladder), and D (the tube that exits the bladder).

Structures A-D are:

A = kidney

B = ureter

C = bladder

D = urethra

Diagram of the human urinary system with labeled parts: A (kidneys), B (the tube that connects the kidneys and the bladder), C (bladder), and D (the tube that exits the bladder).

What is the role of the bladder in the urinary system?

The role of the bladder is to store urine that is produced by the kidneys.

True or False?

The ureter carries urine from the bladder to the exterior of the body.

False.

The urethra carries urine from the bladder to the exterior of the body. The ureters are a pair of tubes that connect the kidneys to the bladder

What are the kidney regions indicated by labels X and Y? (Extended Tier Only)

Diagram of a kidney cross-section showing labelled parts. Label X points to a region towards the centre of the kidney and label Y points to a region close to the outer surface.

The kidney regions are:

X = medulla

Y = cortex

Diagram of a kidney cross-section showing labelled parts. Label X points to a region towards the centre of the kidney and label Y points to a region close to the outer surface.

Define the term nephron. (Extended Tier Only)

Nephrons are tiny tubes found in the kidney. Each kidney contains many nephrons, the role of which is to produce urine.

True or False?

The Bowman's capsule of each nephron surrounds a glomerulus. (Extended Tier Only)

True.

The Bowman's capsule directly surround the glomerulus, a ball of blood vessels from which the blood filters into the nephron.

Where in the kidney nephron does filtration occur? (Extended Tier Only)

Filtration, or ultrafiltration occurs between the glomerulus and the Bowman's capsule.

Name the substances that are forced out of the capillaries during filtration. (Extended Tier Only)

Substances that are forced out of the capillaries during ultrafiltration are:

Glucose

Water

Urea

Salts

These molecules form the glomerular filtrate.

True or False?

All of the substances filtered by the glomerulus are reabsorbed into the blood further along the nephron. (Extended Tier Only)

False.

Substances that are reabsorbed further along the nephron include:

all of the glucose

some of the ions

most of the water

Urea and excess substances are not reabsorbed.