Digestive and Renal System Functions Explained

b) Describe the function of the digestive system, including how waste is removed from the body.

QUESTION 7 a) Identify the FOUR main parts of the renal system (also known as the urinary system) and provide a brief explanation of the function of each.

Function of the Digestive System

The digestive system is responsible for breaking down food into smaller, absorbable components, allowing the body to extract and utilize nutrients for energy, growth, and cellular repair. The process involves several key functions:

1. Ingestion: The intake of food and liquids through the mouth.
2. Digestion: The mechanical and chemical breakdown of food. Mechanical digestion occurs through chewing and the churning action of the stomach, while chemical digestion involves enzymes breaking down food into simpler molecules.
3. Absorption: The small intestine is primarily responsible for absorbing nutrients (such as carbohydrates, proteins, fats, vitamins, and minerals) into the bloodstream.
4. Transportation: The digestive system moves food through the gastrointestinal tract via peristalsis, a series of wave-like muscle contractions.
5. Elimination: Waste products and indigestible parts of food are eliminated from the body. This occurs primarily in the large intestine, where water is reabsorbed, and the remaining material is formed into feces. The feces are stored in the rectum until they are expelled from the body through the anus during the process of defecation.

Renal System (Urinary System)

The renal system, also known as the urinary system, is responsible for filtering blood, removing waste products, and regulating fluid and electrolyte balance. The four main parts of the renal system are:

1. Kidneys: The kidneys are two bean-shaped organs that filter blood to remove waste products and excess substances, producing urine. They also regulate blood pressure, electrolyte balance, and acid-base balance.

2. Ureters: The ureters are muscular tubes that transport urine from the kidneys to the bladder. They use peristaltic movements to push urine downward.

3. Bladder: The bladder is a hollow, muscular organ that stores urine until it is ready to be expelled from the body. It can expand and contract, allowing for the temporary storage of urine.

4. Urethra: The urethra is a tube that carries urine from the bladder to the outside of the body during urination. In males, it also serves as a passage for semen during ejaculation.

Together, these components work to maintain homeostasis by regulating the composition of blood and ensuring the removal of waste products from the body.