C3 Are you what you eat? Flashcards
carbohydrates
- Most come from plants (lactose → milk)
- Contains carbon, hydrogen and oxygen = CHO
- 2H and 1O for every C
- Monosaccharides -> Disaccharides -> polysaccharides
carbohydrates
- Glucose -> produce ATP
Energy - warmth, movement, brain activity, muscle contraction - Excess glucose → glycogen and stored in muscles and liver cells
- Excess beyond storage → fat
- Sugar becomes part of DNA, RNA, ATP, glycoproteins, glycolipids
Lipids
- Composed mostly of carbon, hydrogen, oxygen, sometimes nitrogen and phosphorus
- Lower ratio of O to C than carbs, relatively insoluble in water
- Ingested and broken down to release energy
- Triglycerides makes up 95% of fats in body
- Glycerol + 3 fatty acids
Proteins
- Amino acids are not stored in the body
- Essential → can be produced, body must obtain from the diet
- Non essential → still required by body, but can be synthesised from amino acids
Functions of proteins
Regulate body functions
Vitamins
- Organic molecules in very small quantities in food
- Essential for normal metabolism but can’t be produced by the body
- Vitamin k → produced by intestinal bacterial
- Fat soluble (ADEK) water soluble (BC)
Too much Vitamin
C - stomach inflammation, diarrhea
A - toxic during pregnancy
D - alter calcium metabolism
Vitamin deficits
D - rickets
C - scurvy
B - beriberi
Minerals
- Inorganic nutrients
- Components of coenzymes, some vitamins, haemoglobin, organic molecules
Function - Membrane potential & action potentials
- Add mechanical strength to bones and teeth
- Available from plant and animal based foods
Mineral deficiencies
Iron - anaemia
Potassium - muscle weakness, abnormal heart function
Iodine - goitre
What does the process of digestion do?
Mechanical - breaks large food particles to smaller ones
Chemical - breaking of covalent bonds by digestive enzymes
role of insulin and glucagon
blood sugar homeostasis
role of lipase
breakdown lipids
role of pancreatic amylase
breakdown carbohydrates
role of trypsin
breakdown proteins
Mucosa
innermost layer, secrets mucus
Submucosa
connective tissue layer, contains blood vessels, nerves
Muscularis
⅔ muscle layers, movement & secretion
Serosa / adventitia
outermost layer, connective tissue, stability
What are the accessory organs of the digestive system?
Liver, gallbladder, pancreas
What are the stages of digestion and where do they occur?
- Ingestion
* Introduction of food into stomach (via mouth) - Mastication
* Chewing → mechanical digestion to break down large particles, facilitates chemical digestion - Secretive
* Lubricate, liquefy, digest - Digestion
* Mechanical and chemical digestion of food into nutrients - Absorption
* Movement of nutrients out of digestive tract into cells - Elimination
* Waste products removed from body; faeces. defecation
How are the products of digestion
- Mouth, stomach, small intestine
- Mechanical digestion breaks down large food particles to smaller ones
- Chemical digestion breaks covalent bonds by digestive enzymes
Absorption of digested products
- Nutrients from the small intestine, water from the large intestine
- Molecules are moved out of digestive tract into circulation for distribution throughout body (via liver)
use of digested nutrients
- Chemicals taken in to the body to
- Produce energy
- Provide building blocks to build other molecules
- Small amounts of vitamins and minerals taken in to body without being digested
use of digested Carbohydrates
- Glucose → produce ATP
- Energy - warmth, movement, brain activity, muscle contraction
- Excess glucose → glycogen and stored in muscles and liver cells
- Excess beyond storage is converted to fat
- Sugars also become part of DNA, RNA, ATP, glycoproteins, glycolipids
use of digested proteins
Globular - haemoglobin
Structural - muscle proteins / CT
Cell membrane transport
Enzymes
Hormones
Antibodies
