Organic vs inorganic LO5

Question 1

Organic molecules/compounds

Answer 1

• contain both carbon and hydrogen
• often very large
  e.g. H2CO3, glucose

Question 2

Inorganic molecules

Answer 2

• all other body chemicals
• do not contain both carbon and hydrogen

Question 3

Macromolecules

Answer 3

Are polymers – chain-like molecules made up of
similar or repeating units called monomers
- 4 classes - carbohydrates, lipids, proteins, nucleic acids

Question 4

Carbohydrates

Answer 4

• Carbohydrates include sugars (saccharides) and starches
• Contain carbon, hydrogen and oxygen in the ratio CH2O

Question 5

Carbohydrate functions

Answer 5

Major function: provide energy for all
cellular functions
Minor function: building materials

Question 6

Lipids

Answer 6

• Include plant and animal fats
• contain carbon, hydrogen and oxygen - the ratio of
  H:O is very high
• There are three main kinds of lipids in the body:
  triglycerides, phospholipids, steroids

Question 7

triglycerides

Answer 7

• long term energy store
• subcutaneous fat (thermal insulation, protection)

Question 8

phospholipids

Answer 8

• Hydrophobic (non-polar) fatty acid tail
• Hydrophillic (polar) phosphate-containing head
  Function:
• phospholipid bilayers form all cell membranes
• transport lipids in plasma

Question 9

steroids

Answer 9

Cholesterol, Hormones, Vitamin D, Bile

Question 10

Nucleic acid

Answer 10

• DNA and RNA
• nucleic acids (phosphate, deoxyribose sugar, base) - monomer

Question 11

DNA

Answer 11

1. self-replication:
   daughter cells have
   identical genetic material
2. provides instructions for
   building every protein in
   the body – the sequence of
   the base molecules (A, T, G
   or C) is a code that defines
   the sequence of amino acids
   in a protei

Question 12

RNA

Answer 12

1. Messenger (mRNA) – a
   copy of the DNA code
2. Ribosomal (rRNA) –
   reads the mRNA code
   and connects amino
   acids
3. Transfer (tRNA) –
   delivers the amino
   acids in the correct
   order to make the
   protein

Question 13

ATP

Answer 13

• Temporary, easily accessible energy
  storage within the cell
• The breakdown of ATP releases energy
  that the cell can use to do work

Question 14

Proteins

Answer 14

• fibrous proteins –> structural roles
• globular proteins –> functional roles

The structure of a protein determines its function

Question 15

Fibrous proteins

Answer 15

• Extended, strand-like
• Insoluble in water à stable
• Major building material in the body à provide mechanical
  support and tensile strength

Question 16

Globular proteins

Answer 16

• Compact, spherical
• Water-soluble –> chemically active
• Crucial role in (all) biological processes –> functional
  proteins

Question 17

Enzymes

Answer 17

• catalyst – a substance that increases the
  rate of the reaction
  Enzymes are biological catalysts
• protein molecules
• do not participate in the reaction but help to form or break chemical bonds
• shape of the active site matches the shape of the substrate
  anabolic - atoms join to make a bigger complex
  catabolic - large molecule into smaller molecules
  exchange reaction - chemical bonds are made and broken

Question 18

Protein structure determines its function

Answer 18

structure determine function
therefore, any chance in structure/shape can alter or destroy the protein and cause it to denature