B2 Flashcards
Molecules too big to pass through the walls of the digestive system
Starch, proteins, fats
Molecules that can pass through the walls of the digestive system
Sugars, amino acids, glycerol and fatty acids
What are carbohydrases?
Digestive enzymes that break down starch to sugars
What are proteases?
Digestive enzymes that digest proteins to amino acids
Lipase?
Digests fat into fatty acids and glycerol
Mouth
Food is moistened with saliva from to salivary glands
They produce amylase
Food is chewed to form a bonus
Oesophagus
A tube that takes food from the mouth to the stomach. It’s lined with muscles that contract to help the ball of food move along by peristalsis
Liver
Where bile is produced
Bile
Neutralises stomach acid and emulsifies fats
Gall bladder
Where bile is stored
Stomach
Pummels the food
Produces Pepsin
Hydrochloric acid
Why does the stomach produce hydrochloric acid
To kill bacteria
To give the right pH for the protease enzyme
Pancreas
Produces protease, amylase, and lipase enzymes, it releases these into the small intestine
Small intestine
Produces protease, amylase and lipase enzymes to complete digestion.
This is where the food is absorbed out into the body
Large intestine
Where excess water is absorbed from the food
Osmosis
The movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration
Root hairs take in water by which process
Osmosis
Root hairs take in minerals by which process
Active transport
How does active transport work
Because the concentration of minerals in the soil is pretty low, it uses energy from respiration to help the plant pull minerals into the root hair against the concentration gradient
Xylem tubes
Transport water and minerals from the root to the rest of the plant
Phloem tubes
Transport sugars from the leaves to growing and storage tissues
Transpiration.
The loss of water from a plant
Digestion
The breakdown of food into soluble products which are then absorbed into the body
Chromosomal DNA
One long circular chromosome
Controls the cells activities and replication
Plasmids
Small loops of extra DNA that aren’t part of the chromosome
Contain genes for things like drug resistance and can be passed between bacteria
Flagellum
Rotates to make the bacterium move
What are the base pairs
Adenine- Thymine
Guanine- Cytosine
Who discovered the structure of DNA
Watson, Crick, Franklin and Wilkins