biological molecules Flashcards
the most common compounds
water & carbohydrates, proteins, lipids(fats) and nucleic acids (DNA&RNA)
carbohydrates are made from
carbon, hydrogen and oxygen
the chemical reaction that breaks down carbohydrates is
respiration
respiration releases energy in the form of
ATP
the smallest units of carbohydrates are
simple sugars
e.g. glucose and fructose
glucose + fructose ->
sucrose (plant sugar bought from the supermarket)
two sugar molecules ______ be joined together
can
many sugar molecules (1000’s) are joined together to make
complex carbohydrates
(carbohydrate) starch is used to
store glucose in plants
(carbohydrate) glycogen is used to
store glucose in animals and fungi
why are starch and glycogen better storage molecules
they are less soluble than simple sugars (less effect on water movement in&out of cells)
fats (lipids) are made from
carbon, hydrogen and oxygen
fats (lipids) are made from _ fatty acids joined to …
3 fatty acids joined to a glycerol molecule
fats (lipids) can be used to store
energy (that can also be used in respiration)
fats (lipids) are a part of
cell membranes
fats (lipids) can be used for thermal
insulation
fats (lipids) can be used for electrical
insulation (around nerve cells)
fats (lipids) can help with b_______
buoyancy - helps marine animals to float
proteins are made from
carbon, hydrogen, oxygen and nitrogen (N in proteiN)
proteins are made from many _____ acids …
amino acids joined together
there are __ different amino acids
20 - meaning millions of different protein structures
the _____ of a protein helps it
shape - helps it carry out its job
protein is used for __________ molecules e.g.
structural molecules
e.g. collagen and keratin
proteins can control ________ reactions
chemical - (these are enzymes?)
(topic notes pg7???)
proteins can be used for messenger
molecules - hormones
proteins can combat
disease - antibodies
proteins can be used for t_______ e.g.
transport
- haemoglobin & cell membrane proteins
