2 c Biological molecules Flashcards
2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14
What are the 3 main molecules in organisms
-Carbohydrates
-Proteins
-Lipids
Chemical elements of carbohydrates
Carbon, oxygen, hydrogen
Chemical elements of protein
Carbon, oxygen, hydrogen, nitrogen (sometimes others)
Chemical elements of lipids
Carbon, hydrogen, oxygen
What are glucose and fructose
Monosaccharides
What happens when glucose is broken down
It releases a lot of energy
How are disaccharides made
Two monosaccharides joint together
How is maltose formed
Two glucose molecules
How is sucrose formed
One glucose & one fructose molecule
How is a polysaccharide formed
Lots of monosaccharides joint together
Examples of polysaccharides
Starch, glycogen, cellulose
Why are polysaccharides useful as storage molecules
Theyre insoluble
What are most of lipids made up of in the body
Triglycerides
What are lipids divided into
Fats (solid at room temperature)
Oils (liquid at room temperature)
What are proteins made of
Long chains of amino acids
How many amino acids are there
20
Examples of proteins
Enzymes, haemoglobin, ligaments & keratin
What solution is added to test for glucose
Benedicts solution
What colour change would be positive for test for glucose
Blue to orannge / brick red
What is used to test for starch
Iodine solution
What colour change would be a positive test for starch
orange-brown to blue-black
What solution is used to test for proteins
Biuret solution
What colour change would be a positive test for proteins
Blue to purple
What liquid is used to test for lipids
Ethanol
What would form to signify a positive test for lipids
Cloudy emulsion
Name the safety measures for
-Biuret solution & iodine
-Sodium hydroxide
-Ethanol
-Irritants to the eyes
-Corrosive
-Flammable
What are enzymes
Biological catalyst that speeds up the rate of reaction without being changed
Why are enzymes necessary
They maintain the reaction speeds of metabolic reactions
How are enzymes specified to one particular substrate
They have an active site which has a specific shape
What is the name when a substrate moves into the active site
enzyme-substrate complex
What’s the optimum temperature for enzymes
37ºC
What will happen if the temperature is too high for enzymes
The bonds that hold the enzymes together will break: Denature
What happens during denaturation
The active site changes shape, the substrates no longer fit. Its irreversible
Why do enzymes work less at lower temperatures
The molecules have less kinetic energy so they move slower and there’s less collision
What is the optimum pH for most enzymes
7
What happens if the pH is too high or too low for the enzyme
The bonds can be disrupted/destroyed; denaturation
What are the factors that affect the activity of enzymes
-Temperature
-pH