1.2 — carbohydrates: introduction Flashcards
what are carbohydrates?
carbohydrates are molecules that contain the elements carbon, hydrogen and oxygen
what does the ‘carbo’ in carbohydrates show about a biological molecule?
that the molecule contains the element carbon
what does the ‘hydrate’ in carbohydrates show about a biological molecule?
that it contains hydrogen and oxygen atoms in a ratio of 2:1 (like water — H2O)
what is the general formula for a carbohydrate?
Cx(H2O)Y
what are the 5 roles of carbohydrates in living organisms?
- energy supply for cells — the main role
- energy storage — sugars can be stored as complex carbohydrates (e.g. starch or glycogen)
- structural components — cellulose and chitin are used in cell walls
- cellular recognition — glycoproteins help cells identify each other and communicate
- building blocks for biological molecules — deoxyribose and ribose can be used to make nucleic acids
how many subunits does a monosaccharide contain?
one
give three examples of a monosaccharide:
glucose, fructose and galactose
what is a monosaccharide’s main function?
energy source
how many subunits does a disaccharide contain?
two
give three examples of a disaccharide:
maltose, sucrose and lactose
what is a disaccharide’s main function?
transport form
how many subunits does a polysaccharide have?
many
give three examples of a polysaccharide:
starch, glycogen, cellulose
what is a polysaccharide’s main function?
storage form
what is an example of carbohydrates being used for energy storage in living organisms?
sugars can be stored as complex carbohydrates, e.g. starch or glycogen
what is an example of carbohydrates being used for structural components in living organisms?
cellulose and chitin are used in cell walls
what is an example of carbohydrates being used for cellular recognition in living organisms?
glycoproteins help cells identify each other and communicate
what is an example of carbohydrates being used for building blocks for biological molecules in living organisms?
deoxyribose and ribose sugars can be used to make nucleic acids