Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
98 Cards in this Set
- Front
- Back
|
7 food groups that sources as energy |
Fats Minerals Water Fibre Proteins Vitamins Carbohydrates |
|
|
Alimentary canal |
Continuous tube from mouth to anus |
|
|
Lining of Alimentary canal |
Surface through which nutrients are absorbed |
|
|
Mouth |
Where chemical and physical digestion begins |
|
|
Ingestion |
Intake of food |
|
|
Mechanical digestion |
Chewing using our teeth (Mastication) |
|
|
Chemical digestion |
-using enzymes/ chemicals -saliva contains mucus and salivary amylase which begins breaking large stack molecules into smaller molecules |
|
|
Types of treth |
Canine Incisors Premolars Molars |
|
|
Canines |
Sharp pointed teeth used to bite and tear food |
|
|
Incisors |
Small rectangular shaped teeth Found between canine for cutting food |
|
|
Premolars |
Found behind canines Ground soft food |
|
|
Molars |
Found behind premolars Grind hard food |
|
|
Oesophagus |
•Double layer of muscle: Circular and longitudinal •mucus is secreted to lubricate it |
|
|
Peristalisis |
Contraction of bands of circular muscle moves in a wave along oesophagus pushing food in front of it |
|
|
Stomach |
•Mechanical and chemical digestion occurs here • food enters oesophagus, liquids mix with food, digested food leaves |
|
|
Mechanical digestion |
Waves of muscular contraction that move along stomach wall churn food |
|
|
Glandular tissue |
Makes HCl, mucus and protease enzyme |
|
|
Chemical digestiob |
Lining of the stomach (mucosa) secretes gastric juices from gastric glands |
|
|
Gastric juice |
Contains HCl, mucus and digestive enzymes |
|
|
Pyloric sphincter |
Thickening of muscle that constrict to prevent stomach contents from leaving until pushed along peristalsis (2-8hrs) |
|
|
HCl in stomach |
•attacks any microbes that may have been swallowed accidentally when food was eaten •provides perfect conditions for protease enzyme |
|
|
What happens when HCl provides perfect conditions for protease enzyme |
Enzymes digest proteins in swallowed food Proteins are broken down to release amino acids Protease enzymes work best under acidic conditions (pH <7) |
|
|
What are the 3 parts of Small intestine |
Duodenum Jejunum Ileum |
|
|
Duodenum |
Receives materials from stomach through pyloric sphincter |
|
|
How does digestion continue in small intestine |
Intestinal juices Pancreatic juices Bole |
|
|
Intestinal juice |
Secreted by glands in the lining Contains enzymes that conplete digestion |
|
|
Pancreatic juicds |
Secreted by pancreas Enters duodenum Help neutralise acid from stomach |
|
|
What does pancreatic juices contain |
Pancreatic amylase Trypsin (pancreatic protease) Ribonuclease Deoxyribonuclease Pancreatic lipases |
|
|
Bile |
Contains bile salts |
|
|
Bile salts |
Emulsify/ breaks fats into tiny droplets to help digest them |
|
|
Where is the site of absorption |
Small intestine for useful molecules of digested food |
|
|
What does efficient absorption require |
Large surface area |
|
|
What does efficient absorption require |
Large surface area |
|
|
How is large surface area achieved by in small intestine |
•length of ~6m •mucosa have villi which has microvilli |
|
|
How is Villus' structure suitable for nutrient absorption |
•each villi is 1mm long and covered by single layer of cells •lacteals surround by network of capillaries •continue movement brings contact with different parts of intestinal contents |
|
|
How is Villus' structure suitable for nutrient absorption |
•each villi is 1mm long and covered by single layer of cells •lacteals surround by network of capillaries •continue movement brings contact with different parts of intestinal contents |
|
|
Large intestine |
Food enters waste material is left water is left here preventing dehydration Mineral nutrients are absorbed here |
|
|
Rectum |
Storage organ that waste material passes (indigested food) into |
|
|
Rectum |
Storage organ that waste material passes (indigested food) into |
|
|
Faeces |
Solid excremental |
|
|
Rectum |
Storage organ that waste material passes (indigested food) into |
|
|
Faeces |
Solid excremental |
|
|
Tissues in digestive system |
Glandular Muscular |
|
|
Rectum |
Storage organ that waste material passes (indigested food) into |
|
|
Faeces |
Solid excremental |
|
|
Tissues in digestive system |
Glandular Muscular |
|
|
Glandular tissue |
Responsible for production of digestive enzymes |
|
|
Rectum |
Storage organ that waste material passes (indigested food) into |
|
|
Faeces |
Solid excremental |
|
|
Tissues in digestive system |
Glandular Muscular |
|
|
Glandular tissue |
Responsible for production of digestive enzymes |
|
|
Muscular tissue |
Food is kept moving through system from mouth to ants through constant contraction and relaxation |
|
|
How does the diet affect absorption in alimentary canal |
•moves material through alimentary canal •larger meal = greater stretch of stomach that is pushed to small intestine quicker •high protein/fat slow movement from stomach to small intestine •alcohol and caffeine stimulate movements of stomach |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
What happens to defecation in constipation |
Becomes difficult and painful |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
What happens to defecation in constipation |
Becomes difficult and painful |
|
|
Cause of constipation |
Lack of roughage in diet |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
What happens to defecation in constipation |
Becomes difficult and painful |
|
|
Cause of constipation |
Lack of roughage in diet |
|
|
Roughage |
Cellulose/insoluble fibre (Major component of foods) |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
What happens to defecation in constipation |
Becomes difficult and painful |
|
|
Cause of constipation |
Lack of roughage in diet |
|
|
Roughage |
Cellulose/insoluble fibre (Major component of foods) |
|
|
Diarrhoea |
Frequent defecation of watery faeces |
|
|
How does constipation occur |
If movements of large intestine are reduced and contents remain there for long periods of time (faeces are drier and harder, water absorbed) |
|
|
What happens to defecation in constipation |
Becomes difficult and painful |
|
|
Cause of constipation |
Lack of roughage in diet |
|
|
Roughage |
Cellulose/insoluble fibre (Major component of foods) |
|
|
Diarrhoea |
Frequent defecation of watery faeces |
|
|
Defecation |
Discharge of faeces from bodu |
|
|
Defecation |
Discharge of faeces from bodu |
|
|
Defecation |
Discharge of faeces from body |
|
|
Cause of diarrhoea |
Irritation of small/large intestine •increase peristalsis (contents is moved before enough absorption of water) •bacterial/ viral infection |
|
|
Cause of diarrhoea |
Irritation of small/large intestine •increase peristalsis (contents is moved before enough absorption of water) •bacterial/ viral infection |
|
|
Bowel cancer |
Uncontrolled growth of cells in wall of intestine |
|
|
Cause of diarrhoea |
Irritation of small/large intestine •increase peristalsis (contents is moved before enough absorption of water) •bacterial/ viral infection |
|
|
Bowel cancer |
Uncontrolled growth of cells in wall of intestine |
|
|
Risk factors of bowel cancer |
Overweight Physical inactivity Red and processed meet Low in fibre High alcohol consumption |
|
|
Cause of diarrhoea |
Irritation of small/large intestine •increase peristalsis (contents is moved before enough absorption of water) •bacterial/ viral infection |
|
|
Bowel cancer |
Uncontrolled growth of cells in wall of intestine |
|
|
Risk factors of bowel cancer |
Overweight Physical inactivity Red and processed meet Low in fibre High alcohol consumption |
|
|
Importance of soluble fibre in diet |
Lowers cholesterol levels in blood Decrease risk of he's disease and cancer Blood glucose levels |
|
|
Where is soluble fibre found |
Plants (pectins, gums and mucilage) |
|
|
Why are fats in intestine trapped by soluble fibre |
Helps prevent their absorption by body |
|
|
Corliac disease |
Unable to tolerate gluten |
|
|
Corliac disease |
Unable to tolerate gluten |
|
|
What happens to people if they eat gluten with coeliac disease |
Immune system damages and destroys villi in small intestine |
|
|
Corliac disease |
Unable to tolerate gluten |
|
|
What happens to people if they eat gluten with coeliac disease |
Immune system damages and destroys villi in small intestine |
|
|
Healthy villi |
Nutrients are absorbed Person is nourished |
|
|
Corliac disease |
Unable to tolerate gluten Inherited No cure - just gluten free diet |
|
|
What happens to people if they eat gluten with coeliac disease |
Immune system damages and destroys villi in small intestine |
|
|
Healthy villi |
Nutrients are absorbed Person is nourished |
|
|
Symptoms of coeliac disease |
Muscle cramps Joint pain Tingling in legs |
