Topic 2 - Organisation Flashcards
(22 cards)
Order of organisation
- cells (muscular, glandular, epithelial)
- tissues (muscular, glandular, epithelial)
- organs (glands, stomach, liver, small intestine, large intestine)
- organ system (digestive system)
Enzyme
A biological enzyme that speeds up chemical reactions without being changed or used up
Active site
Area on enzyme where reactions take place
Substrate
Substance(s) that fit into the active site to react and form (a) product(s)
Amylase
Enzyme that breaks down starches into sugars
Protease
Enzyme that breaks down proteins into amino acids
Lipase
Enzymes that break down lipids into glycerol and fatty acids
Function of salivary glands
Produce amylase enzyme in saliva
Function of stomach
- pummels food with muscular walls
- produces protease enzyme, pepsin
- hydrochloride acid production to kill bacteria and to maintain pH 2 for pepsin
Function of liver
Produces bile to neutralise stomach acid and emulsify fats
Gall bladder function
Stores bile before releasing it into the small intestine
Pancreas function
Produces protease, amylase and lipase to go into the small intestine
Small intestine function
- produces protease, amylase and lipase to complete digestion
- where digested food is absorbed into blood
Large intestine
Where excess water is absorbed to form faeces
Rectum
Where faeces is stored
Anus
Where faeces leaves the body
Describe inhaling and exhaling
- air down trachea
- down bronchus
- down bronchiole
- into alveoli and all the way back out
- intercostal muscles (between ribs) and diaphragm contract and relax to push air in and out
Explain alveoli
- one cell thick for easy diffusion
- high surface area
- capillaries connecting directly to veins and arteries which go directly onto heart
Blood vessels in heart
- vena cava (deoxygenated blood from body to right atrium)
- pulmonary artery (deoxygenated blood from right ventricle to lungs)
- pulmonary vein (oxygenated blood from lungs to left atrium)
- aorta (oxygenated blood from left ventricle to body)
- left ventricle has more muscle and is larger than right atrium to pump blood further
Arteries
- blood at high pressure
- thick walls
- muscle and elastic fibres make them strong and allow them to stretch and spring back
Capillaries
- one cell thick
- permeable
- food and oxygen to cells
- waste away from cells
- from arteries to veins
Veins
- lower pressure
- less thick
- bigger lumen (hole)
- valves to prevent back flow
