B2 - Organisation - Cognito Notes Flashcards
What are organelles?
essential components of a cell which serve specific functions (e.g. nucleus, ribosomes, mitochondria)
What are cells?
come in various shapes and sizes using various combinations of organelles (e.g. specialised cells)
What are tissues?
group of similar cells that work together to carry out a particular function
What are organs?
group of different tissues that work together to carry out a particular function
What are organ systems?
group of organs that work together to carry out a particular function
What are organisms?
multiple organ systems working together
What are enzymes?
biological catalysts which increase the speed of a reaction without being changed or used up in the process, large proteins which can fold up to create a unique enzyme
Enzymes have an active site which is complementary to the substrates. If the substrate doesn’t fit, what happens?
The reaction will not be catalysed, showing how specific enzymes are about which reactions they speed up
What is the lock and key model for enzymes?
initially scientists thought the substrate had to fit perfectly into the active site, therefore comparing it to a lock and key
What is the induced fit model for enzymes?
the active site being complementary to the substrate (the enzyme changes shape slightly as it binds to the substrate)
How does temperature affect enzymes?
High temperatures break the bonds that hold enzymes together as the active site starts to change shape. if it changes shape enough, it would be able to bind to the substrate and become denatured
How does pH affect enzymes?
Some bonds will start to break, the active site starts to change shape (substrate will fit but less well. if it changes shape enough, it would be able to bind to the substrate and become denatured
What is bile and what is its function?
bile is a digestive enzyme which helps with the digestion of lipids as it emulsifies them increasing their surface area for lipase to break them down
What digestive enzyme breaks down carbohydrates?
by amylase into maltose
Where is amylase made in the body?
salivary glands, pancreas, small intestines
What digestive enzyme breaks down proteins?
by protease into amino acids
Where is protease made in the body?
stomach, pancreas, small intestines
What digestive enzyme breaks down lipids?
by lipase into glycerol and fatty acids
Where is lipase made in the body?
pancreas, small intestines
What does the digestive system do?
breaks down food into tiny pieces so the body’s cells can absorb them, which is reliant on physical and chemical breakdown
Where are carbohydrates found and what are they used for?
found in starchy foods, provide energy for chemical reactions and movement
Where are lipids found and what are they used for?
found in oily fish + nuts + seeds + avocados, provide energy and insulation
Where are proteins used for?
building blocks for tissue growth and repair
Why are carbohydrates and lipids essential>
for maintaining proper bodily functions
How are vitamins and mineral ions similar?
there are lots of different types of each and we only need them in small amounts
How are vitamins and mineral ions different?
vitamins are organic molecules, minerals are inorganic and simpler
What are some examples of vitamins?
Vitamin A (found in liver + leafy vegs, for good vision, healthy skin + hair), Vitamin C (found in fruit + vegs, for preventing scurvy), Vitamin D (can be made in body via sunlight, found in eggs, oily fish, etc., for absorbing calcium)
What are some examples of mineral ions?
Calcium (found in dairy products + leafy vegs, for strong bones), iron (found in red meats/spinach/beans, imortant component of haemoglobin, could lead to anaemia with too little)
Where is fibre found and what is it used for?
found in wholemeal foods + fruits + vegs, helps food move through intestines properly
Where is water found and what is it used for?
found in drinks + foods like strawberries and oranges, needed for chemical reactions and maintaining the body’s water concentration (lost through sweating, breathing, urinating)
What are carbohydrates made from and what breaks them down?
made from carbon, hydrogen, oxygen atoms and come in different sizes (smallest being simple sugars - monomers), broken down by enzymes in the mouth and small intestine
What are proteins made from and what breaks them down?
made up of longs chains of amino acids bonded together, enzymes in the stomach and small intestine break down proteins into amino acids
What are lipids made from and what breaks them down?
contain a single glycerol molecule attached to three fatty acid molecule, and their length and structure determine whether a lipid is a fat or an oil
How do you prepare foods for food tests?
breaking it down with mortar and pestle > put crushed food in beaker w/ distilled water > mix w/ glass rod until dissolved > filter mixture so any solid chunks are removed
What does the Benedict’s test test for?
reducing sugars
What is the process of the Benedict’s test?
Transfer 5cm cubed of food sample into test tube > set water bath at 75°C > add 10 drops of benedict’s solution > place in water bath for 5 mins > check solution for reducing sugars > Solution changes color based on concentration. (blue = no, green/yellow/brick red = yes)
What does the iodine test test for?
starch
