2.1 Molecules to Metabolism

Question 1

what makes carbon such a dynamic compound?

Answer 1

It has covalent bonds, which means it is strong and stable and it has a complex structure as it has 4 bonds which can be single or double so it can make different elements. It can have a ring or chain structure which will affect its properties.

Question 2

classify and discuss different properties/purposes of the cabon compounds carbohydrates, lipids, proteins and nucleic acids

Answer 2

carbohydrates

• have carbon, hyrodgen and oxygen
• 2 hydrogen to one oxygen

lipids

• insoluble in water e.g. steroids, waxes, fatty acids
• fats if solid at room temp oils if liquid at room temp
• have less oxgyen then carbohydrates

proteins

• composed of carbon, hydrogen, oxgyen, nitrogen 22 also have sulfur
• made of chains of amino acids

nucleic acids

• chains of nucleotides
• contain carbon, hydrogen, oxygen, phosphorus, nitrogen
• RNA and DNA

Question 3

draw and comment on a glucose molecule

Answer 3

• hydroxyl group is OH
• ratio of hydrogen to carbon in 2:1 (12:6)
• 1 + 4 is where the bonding happens
• hexose
• in aform of glucose used by plants to make cellulose the hydroxyl group of carbon 1 points up

Question 4

draw and comment on a ribose molecule

Answer 4

• pentose as 5 carbons
• twice as many hydrogens as carbons 2:1 (10:5)
• ring iwht a side chain
• 1+4 is where the bonding happens

Question 5

draw and comment on an amino acid molecule

Answer 5

• R is the variable and he simplest it can be is a hydrogen
• the NH2 is an amine group
• COOH is a carboxyl group

Question 6

draw and comment on a saturated lipid and an unsaturated lipid

Answer 6

• CH3 is a methyl group
• unsaturated if one or more double bond between the carbons is present
• unsaturated has 2 fewer hydrogens as it has a double bond
• if the double bond is at the end the unsaturated lipid will not have a meythl gourp

Question 7

drawing molecules of common structures

Answer 7

amino –> amine

carboxylix –> carboxyl

Question 8

what are the roles of nucleic acids and proteins (very complex and varied molecules) broadly?

Answer 8

Nucleic acids are DNA and RNA which are chemicals used to make genes

proteins carry out a huge range of task including controlling chemical reactions in the cell by acting as an enzyme

Question 9

UREA as a compound that is produced by living organisms or can be synthesized artifically

Answer 9

urea is a component of urine excreted when there are too many amino acids in the body as a way of removing nitrogen from the amino acids.

In the liver a cycle of reactions occur that are catalyzed by enzymes and this is then transported in the blood stream to the kidneys to be filtered out.

Urea can also be artifically syntehsized using different enzymes than those used in the liver but producing the same end result.

ammonia+ carbon dioxide –> ammonium carbamate –> urea + water

about 100 million tons are produced annually most of which is used for fertilizer due to the high nitrogen content

Question 10

what is metabolism?

Answer 10

metabolism is the web of all enzyme catalysed reactions in a cell or organism.

all living organisms carry out a large number of different chemical reactions. these can be in the cytoplasm or extracellular e.g. digesting food in the small intestine.

metabolism is a pathway which transfers one molecule to another in a series of small steps. Some pathways are chains, some are cycles e.g. urea

in simple prokaryotic cells metabolism is 1000 different reactions

Question 11

what is anabolism?

Answer 11

anabolism is a part of metabolism and is the synthesis of complex molecules from simple molecules. This includes formation of macromolecules from monomers by condensation reactions.

–> build up of larger molecules from smaller ones e.g. anabolic steroids promote body building

anabolism requires energy ATP

process using anabolism

1. protein synthesis
2. DNA synthesis during replication
3. photosynthesis
4. synthesis of complex carbohydrates inclusing starch, cellulose and glycogen

Question 12

what is catabolism?

Answer 12

catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers

–> larger –> smaller

it releases energy which can sometimes be captured as ATP

catabolism is used in these processes

1. digestion of food
2. cell respiration in which glucose or lipids are oxidised to carbon dioxide and water
3. digestion of complex carbon compounds in dead organic matter by decomposers