Excretory and DIgestive system Flashcards
(27 cards)
the main functions of the excretory system?
Excretion of metabolic waste products (e.g., urea, uric acid, creatinine).
Osmoregulation: Regulating the balance of water and electrolytes in the body.
Acid-base balance: Maintaining pH levels in the blood.
structure of the kidney?
The kidney has two main parts:
Cortex: Contains the nephrons responsible for filtration.
Medulla: Contains the loop of Henle and collecting ducts for water and solute concentration.
function of the nephron?
Filtration: Blood is filtered in the glomerulus, and waste products are separated.
Reabsorption: Essential substances like glucose, water, and ions are reabsorbed into the blood in the proximal convoluted tubule and loop of Henle.
Secretion: Additional waste products are secreted into the urine in the distal convoluted tubule.
role of the loop of Henle?
The loop of Henle creates a salt gradient in the kidney’s medulla, which is crucial for water reabsorption and concentration of urine.
The descending limb allows water to leave, and the ascending limb actively transports salts, making the medulla more hypertonic.
What are the primary hormones involved in kidney function?
Antidiuretic Hormone (ADH): Increases water reabsorption by the kidneys, making urine more concentrated.
Aldosterone: Increases sodium reabsorption, which also increases water retention.
Renin: Stimulates aldosterone release in response to low blood pressure.
What is glomerular filtration rate (GFR), and why is it important?
GFR is the rate at which blood is filtered through the glomerulus.
A normal GFR is around 90-120 mL/min, and it’s an important measure of kidney function.
Low GFR can indicate kidney disease or dysfunction.
What is dialysis, and when is it used?
Dialysis is a procedure that performs the function of the kidneys when they are unable to filter waste.
It uses a semipermeable membrane to remove waste products and excess fluids from the blood, typically used in chronic kidney disease or renal failure.
parts of the digestive system?
Mouth: Chewing and saliva begin digestion.
Oesophagus: Transports food to the stomach.
Stomach: Secretes gastric acid and enzymes for protein digestion.
Small intestine: Absorbs nutrients with help from villi.
Large intestine: Absorbs water and electrolytes, forming stool.
Accessory organs: Liver, pancreas, gallbladder.
role of saliva in digestion?
Saliva contains amylase, which breaks down starches into simple sugars.
It also provides mucus for lubrication, and antibacterial agents that protect the mouth.
How does acid secretion in the stomach aid digestion?
Hydrochloric acid (HCl) creates an acidic environment for enzyme activation (e.g., pepsin for protein digestion) and helps kill bacteria in food.
What is peristalsis and its function in the digestive system?
Peristalsis is the wave-like contraction of smooth muscles in the digestive tract that moves food along.
It starts in the oesophagus and continues through the stomach and intestines, aiding in the movement and digestion of food.
function of the small intestine in digestion?
The small intestine is responsible for nutrient absorption.
It has villi and microvilli that increase surface area for the absorption of nutrients into the bloodstream.
role of the pancreas in digestion?
The pancreas secretes digestive enzymes (amylase, lipase, proteases) into the duodenum for the breakdown of carbohydrates, fats, and proteins.
It also secretes bicarbonate to neutralise stomach acid in the small intestine
what is bile and how does it aid digestion??
Bile is produced by the liver and stored in the gallbladder.
It contains bile salts that emulsify fats, making them easier to digest by lipases in the small intestine.
What is gastric reflux Gastroesophageal reflux disease (GERD), and what causes it?
Gastroesophageal reflux disease (GERD) is caused by the backward flow of stomach acid into the esophagus, leading to symptoms like heartburn and regurgitation.
It’s commonly caused by a weakened lower oesophageal sphincter.
What is liver function, and why is it important?
The liver detoxifies harmful substances, produces bile for fat digestion, and stores glycogen.
It also synthesises proteins like albumin and clotting factors.
role of the large intestine in digestion?
The large intestine absorbs water and electrolytes from undigested food, forming stool.
It also houses beneficial bacteria that aid in the fermentation of undigested carbohydrates.
What are the signs and symptoms of irritable bowel syndrome (IBS)?
IBS is characterised by abdominal pain, bloating, diarrhea, and/or constipation.
The exact cause is unknown but may involve gut motility and stress factors.
What is celiac disease, and how does it affect digestion?
Celiac disease is an autoimmune disorder where consumption of gluten damages the small intestine lining, leading to malabsorption of nutrients.
What are peptic ulcers, and what causes them?
Peptic ulcers are sores that form on the stomach lining or the duodenum.
They are commonly caused by H. pylori bacterial infection or long-term NSAID use
How do macronutrients contribute to digestion?
Carbohydrates: Broken down into glucose for energy.
Proteins: Broken down into amino acids for tissue repair.
Fats: Broken down into fatty acids and glycerol for energy and cell membrane formation.
In which layer is the ‘proximal convoluted tubule’
found in the kidney??
the cortex
The bladder is controlled by which pathway and which system??
The bladder is controlled by the parasympathetic pathway and
the somatic nervous system
constituents of saliva??
pn
mucus
dissolving agents
amylase
