Chemical Components of Cells

Question 1

What element is life based on

Answer 1

Life is based on carbon atoms and chemical reactions that take place in solution. This is all dominated and coordinated by polymeric molecules.

Question 2

96.5% of living organisms weight consists of just…

Answer 2

• Carbon
• Nitrogen
• Oxygen
• Hydrogen

Question 3

Cells contain 4 families of small organic molecules

Answer 3

• Sugars
• Fatty Acids
• Amino Acids
• Nucleotides

Question 4

The building block of the cell is Sugars. What is the larger unit of the cell?

Answer 4

Polysaccharides

Question 5

The building block of the cell is Fatty Acids. What is the larger unit of the cell?

Answer 5

Fats/ Lipids/ Membranes

Question 6

The building block of the cell is Amino Acids. What is the larger unit of the cell?

Answer 6

Proteins

Question 7

The building block of the cell is Nucleotides . What is the larger unit of the cell?

Answer 7

Nucleic Acids

Question 8

Whats is the main use of sugars

Answer 8

Energy source for cells and subunits for polysaccharides

Question 9

What are the different sugar types

Answer 9

Monosaccharides 
Disaccharides 
Polysaccharides
Aldoses 
Ketoses 
Oligosaccharides

Question 10

How are monosaccharides formed

Answer 10

Condensation and/or Hydrolysis

Question 11

How are Disaccarides formed

Answer 11

Formed by condensation and/or hydrolysis

Question 12

How are polysaccharides and oligosaccharides formed

Answer 12

Polymerisation of monosaccharides leads to the formation of oligosaccharides and polysaccharides

Question 13

What structure do sugars exist in

Answer 13

Ring structures as aldehyde/ketone groups of sugar react with -OH(hydroxyl) group

Question 14

Small oligosaccharides can link with lipids or proteins to form?

Answer 14

Glycolipids or glycoproteins

Question 15

Aldoses and Ketoses have…

Answer 15

An aldehyde group (CH=O) or a ketone group.

Question 16

Fatty acids - Main use

Answer 16

Main components of cell membranes. They are used for their construction and the membranes are largely composed of phospholipids

Question 17

The two main parts of the fatty acids structure

Answer 17

Hydrocarbon tail and a hydrophilic head

Question 18

The Hydrocarbon tail can vary

Answer 18

These can be saturated or unsaturated. This accounts for the difference between hard and soft margarine. The addition of hydrogen to unsaturated bonds results in saturated C-C bonds, increasing the melting point thus “hardening” it.

Question 19

Fatty acids have concentrated food reserves in cells

Answer 19

-These are stores through ester linkage to glycerol which forms triglycerols
These are 3 fatty acid chains joined to 1 glycerol molecule
- They are stores in the cytoplasm of cells
- 6 times more energy than glucose by weight

Question 20

Fatty acids are Amphipathic.

What does this mean?

Answer 20

They are both hydrophillic and hydrophobic. This induces the membrane forming ability, produces a lipid bilayer

Question 21

Amino acids are…

Answer 21

The sub units of proteins

Therefor proteins are just amino acid polymers

Question 22

Amino acids all possess what groups

Answer 22

Carboxylic acid group
Amino Acid Groups

This produces polarity

Question 23

Amino acids all contain how many carbon atoms

Answer 23

A single carbon atom

alpha- carbon

Question 24

Where does the chemical varieties in amino acids come from

Answer 24

The side chains

Question 25

What bond is between amino acids

Answer 25

Peptide bond. | This means a chain of amino acids is a peptide

Question 26

What are the main units of Nucleotides

Answer 26

They are the subunits of DNA and RNA

Question 27

What is the structure of Nucleotides

Answer 27

They are nitrogen containing ring compounds (the base) linked to a 5 carbon sugar. They carry at leas 1 phosphate group. The bases come together in different orders which create different nucleotides

Question 28

-L- and D- optical isomers… .

Answer 28

only L- isomers in proteins | -side chains can be basic, acidic, polar, non-polar

Question 29

Bases in nuceotides are either

Answer 29

Purines (guanine(G) + adenine(A)) OR Pyrimidines (cytosine( C) +thymine(T) + Uracil(U))

Question 30

What do nucleotides act as

Answer 30

Short term carriers of energy

Question 31

Nucelotides come together to form

Answer 31

Adenosine Triphosphate (ATP) this is made of 3 phosphates linked by the energy rich phosphoanhydride bonds. When there rupture energy is released

Question 32

The most fundamental role of nucleotides is

Answer 32

Storage and retrieval of biological information through the construction of nucleic acids. These are linked by phosphodiester bonds. Ribose gives ribonucleic acids (RNA) and deoxyribose gives deoxyribonucleic acids (DNA) - DNA double stranded -> GATC, - RNA single stranded -> GAUC The linear sequence encodes information -G and C have triple bond but A=T is only double bond (or A=U)