biological molecules + Enzymes Flashcards
What is the purpose of carbohydrates
To be used by the process of respiration to make energy for cells
Which sugar is found in most processed sweet foods
Sucrose
Name two Monosaccharides
Glucose
Fructose
Name three polysaccharides
Starch
Glycogen
Cellulose
What are starch, cellulose and glycogen made of
Chains of glucose
Give three examples of disaccharides
Lactose
Maltose
Sucrose
What is the main sugar transported through plant cells
Sucrose
Where is most carbohydrate in our body found from
Starch
What is the only form of carbohydrate that the human body can process
Glucose
Why is starch considered a storage carbohydrate
Because it is insoluble
What is the main form of storage for plants
Starch
What is the main storage form for humans and animals
Glycogen
Which tissues is glycogen found in
The liver and muscles
Why can humans not digest cellulose
Because our gut does not contain the enzyme needed to break it down
What do humans use cellulose for and why
For dietary fibre, because it provides the food in the gut with something to push against and so keeps the food moving
What are three purposes of lipids
to provide the body with an energy store
To make cell membranes
To provide insulation
What is the percentage mass of carbohydrates in the body
1%
What three elements do lipids contain, and explain the oxygen concentration compared to a carbohydrate
hydrogen, carbon and oxygen(but this is less than a carbohydrate)
What is the state of plant lipids at room temperature
Liquid
Name the three elements present in carbohydrates
Oxygen, hydrogen, carbon
What does insulation do
Reduces heat loss through the body
What are most lipids made from
One glycerol molecule chemically bonded to three fatty acids
What two types of lipids in excessive amounts can cause heart disease?
Saturated fats and cholesterol
Name two foods and one place in the body wher cholestrerol can be found from
Meat, eggs and from the liver
Where are saturated fats found from and where are unsaturated fats found from
Saturated- animal based foods
Unsaturated- plant based
What is a “fat” at room temperature
solid
Give six examples of lipids
Meat, butter, oil, milk, cheese, egg
What is the percentage mass of protein in the body
18%
What is protein made from
Chains of amino acids
How many types of amino acids are there
20 types
What is a peptide
A short chain of amino acids
How are different proteins formed
When there is a change in the order of amino acids
What determines the function of a protein
The shape of a protein, determined by the order of amino acids
Why is ethanol used in the lipids food test
Because fats and lipids are insoluble in water
What is the name of the test for glucose
Benedict’s test
What is the name for the test for protein
Biuret test
Describe the test for glucose
Place crushed food sample in a test tube and stir it with distilled water
add a few drops of Benedict’s solution
Place in a heated water bath for water to boil
should turn orange-red of glucose is present