biological molecules

Question 1

what are carbohydrates and lipids made up of

Answer 1

carbon, oxygen and hydrogen

Question 2

what chemical elements are proteins made up of

Answer 2

carbon
hydrogen
oxygen
nitrogen
sulfur

Question 3

what chemical elements are found in nucleic acids

Answer 3

carbon
hydrogen
oxygen
nitrogen
phosphorus

Question 4

what are some of the important properties of water

Answer 4

metabolic importance
high heat capacity
high heat of vapourisation
cohesive properties
useful as a solvent

Question 5

what is the polarity of water

Answer 5

water is a polar molecule
the hydrogen atoms are slightly positive and the ocygen are slightly negative

Question 6

how is hydrogen bonding present in water

Answer 6

the polarity of water molecules means that they are attracted to one another

Question 7

why is water needed as a metabolite

Answer 7

it is needed for hydrolysis and condensation reactions such as making ATP and breaking ATP to release energy

Question 8

why is water’s high heat of vaporisation needed

Answer 8

a lot of energy is needed to separate the water molecules from each other meaning that it takes a lot of energy for the water to evaporate, when water evapourates becuase energy is used it cools down the surrounding area, this is used in temperature regulation

Question 9

why is the high heat capacity useful in water

Answer 9

water takes a long time to heat and cool this means that water can be used in warm blooded animals to evenly disperse heat within their bodies

Question 10

why is it important that water is a good solvent

Answer 10

water is a good solvent because ions and polar molecules can easily dissolve into it this is because water is di-polar

Question 11

why is it important that water has cohesive properties

Answer 11

the strong attraction between water molecules is important so that water can be transported throughout plants

Question 12

why is water seen as a good habitat

Answer 12

water is a good habitat because it is highly stable

Question 13

what are monomers

Answer 13

monomers are single sub-units eg monosaccharides, nucleotides and amino acids

Question 14

what are polymers

Answer 14

polymers are complex molecules made up of multiple monomers joined through condensation reactions eg protein, DNA and starch

Question 15

what are monosaccharides

Answer 15

they are simple sugars eg glucose, galactose and fructose

Question 16

what is glucose

Answer 16

glucose is a hexose sugar that is an important source of energy and in respiration energy released from glucose is used to make ATP

Question 17

what is a disaccharide

Answer 17

when two monosaccharides are joined through a condensation reaction, eg maltose, sucrose and lactose

Question 18

what are polysaccharides

Answer 18

they are formed when multiple monosaccharides are joined together with glycosydic bonds, the chain can be branched/ unbranched anf they can contain different monosaccharides eg starch and glycogen

Question 19

what is starch

Answer 19

starch is the main store of energy in plants, starch doesnt change the water potential and is made up of amylose and amylopectin

Question 20

what is amylopectin

Answer 20

it is a highly branched chain of alpha glucose, becuase it is branched glucose molecules are easily accessed by enzymes therefore there is a quick energy release

Question 21

what is amylose

Answer 21

amylose is a linear chain of alpha glucose, it is not branched however it can coil meaning that it is a highly compact energy store

Question 22

what is glycogen

Answer 22

glycogen is the main energy store in humans, it is highly branched and means that energy is easily and quickly released due to enzymes to be able to access the glucose molecules easily

Question 23

what is cellulose

Answer 23

cellulose makes up plant cell walls, ut us a long chain of beta glucose molecules which are unbranched, these chains are held together by hydrogen bonds

Question 24

triglycerides

Answer 24

triglycerides are made up of one glycerol and 3 fatty acids joined to the glycogen by ester bonds

Question 25

what is the structure of fatty acids

Answer 25

they are made of hydrocarbon chains they can be saturated and unsaturated

Question 26

what is a saturated fatty acid

Answer 26

they have only single carbon to carbon bonds they are solid at room temperature and are found commonly in animal products

Question 27

what are unsaturated fatty acids

Answer 27

they have at least one double carbon to carbon bond, they are normally liquid at room temperature such as oil

Question 28

what are the functions of fatty acids

Answer 28

-energy release, chemical energy is stored in fatty acid tails lots of energy is released when these are broken down -they repel water, they form lipid droplets which are formed beacuse they are both hydrophobic and hydrophylic this means that they are insoluble and therefore dont affect the cells water potential

Question 29

phospholipids

Answer 29

they form bilayers, they have 2 fatty acids rather than 3 and they have a phosphate group

Question 30

proteins

Answer 30

proteins are made up of multiple amino acids joined by peptide bonds

Question 31

What are the components of amino acids

Answer 31

amino group carboxyl group hydrogen atom r group/ side group

Question 32

r groups

Answer 32

the r groups determine how the amino acids interact with other amino acids within the polypeptide

Question 33

the levels of protein structure

Answer 33

primary-the sequence of animo acids secondary-the hydrogen bonds that determine whether the amino acids for an alpha-helix or a beta pleated sheet tertiary-the bonds involved with the folding of the protein -hydrogen bonds -ionic bonds -disulphide bridges -hydrophobic interactions quarternary-2 or more polypeptide chains, multiple polypeptides joining to form a protein eg haemoglobin has 4 polypeptides

Question 34

globular proteins

Answer 34

have a mostly round structure, they are soluble in water, they are enzymes, messengers and structural proteins

Question 35

fibrous proteins

Answer 35

they are long and narrow and are insoluble in water, they are used for structural support in cells