U1 - L1 Chemical and physical bases of life

Question 1

6 levels of organization

Answer 1

1. Chemical level
   * Atoms combine to form molecules
2. Cell level
   * Molecules form organelles such as the nucleus and mitochondria which make up cells
3. Tissue level
   * Similar cells and surrounding materials make up tissues
4. Organ level
   * Different tissues combine to form organs, such as the urinary bladder
5. Organ system level
   * Organs such as the urinary bladder and kidneys make up an organ system
6. Organism level
   * Organ systems make up an organism

Question 2

Chemical composition of living beings:

Answer 2

Bio elements:
* chemical elements in living beings
* Linked together by chemical bonds to form biomolecules
Examples:
* Oxygen
* Carbon
* Hydrogen
* Potassium
* Calcium hydroxide
* Sodium

Question 3

Biomolecules types

Answer 3

Biomolecules: combination of molecules

1. Inorganic:
   present in the living being but not formed by the living being
   Simple molecules that may/may not have carbon
   H20, CO2, NH3 (ammonia)
2. Organic:
   Carbon chain + hydrogen + (other)
   In nature there are only 4 organic molecules
   * Carbohydrates

Question 4

Structure of carbohydrates:

Answer 4

Made up of carbon, hydrogen and oxygen only
1C: 2H: 1O ratio

Question 5

Function of carbohydrates: - 4

Answer 5

• Provide fuel for the body - through glucose being used to generate ATP
• Acts as an energy store - glycogen is a storage form of glucose
• Cell membrane
• DNA/RNA

Question 6

Types of carbohydrates:

Answer 6

1. Monosaccharide (energy)
   Made of 1 sugar molecule
   Ex. glucose, fructose
2. Disaccharides
   Made of 2 sugar molecules
   Ex. lactose, sucrose,
   Formation:
   Type: condensation reaction
   Monosaccharide + monosaccharide → disaccharide + water
3. Polysaccharides (storage)
   Made up of multiple sugar molecules
   Ex. glycogen, starch, cellulose
   * Lipids

Question 7

Structure of lipids:

Answer 7

• Made up of carbon, hydrogen, oxygen

Question 8

Function of lipids:

Answer 8

• Energy storage
• Fuel
• Cell membranes
• Hormones

Question 9

Types of lipids:

Answer 9

1. Unsaturated:
   * Not all carbon molecules at the end of the fatty acid tail have 2 hydrogens bonded to it
   * Not full of hydrogen
   * Solid at room temperature ex. Butter
   * Originated from plant based foods
   * More healthy = increase good cholesterol
2. Saturated:
   * All carbon molecules at the end of fatty acid tail have 2 hydrogen bonded to it
   * Full of hydrogen
   * Liquid at room temperature ex. Oil
   * Originates from animal sources
   * Less healthy = increases bad cholesterol

Question 10

functions of lipids in cells - 3

Answer 10

1. Energy storage in adipose cells: triglycerides
2. Structural component of cells: phospholipids and cholesterol
3. Chemical reaction modulator (biocatalyst) for hormones

Question 11

Sources of lipids (fats):

Answer 11

Meat
Dairy
Vegetable oil
Fish oil
Seeds
Eggs
Milk
Nuts

Question 12

protein functions - 8

Answer 12

Structure: collagen
Transport molecule: lipoproteins, hemoglobin
Contractile: actin, myosin
Enzymes: lactase
Protection : immunoglobulins
Energy storage: ovalbumin
Homeostatic: albumin
Hormonal: insulin

Question 13

what are protein made of

Answer 13

amino acids

Question 14

Structure of proteins

Answer 14

• Made up of carbon, hydrogen, nitrogen and oxygen
• A protein is made of repeating blocks of amino acids
• Chains of amino acids fold to form tridimensional structures in space

Question 15

Sources of protein

Answer 15

Meat
Fish
Dairy
Eggs
Pulses
Cereals

Question 16

nucleic acids

Answer 16

• There are 2: DNA and RNA
• Long chains of nucleotides
  
  • Nucleotides: phosphate group + carbohydrate + nitrogenous base

Question 17

Difference between DNA and RNA

Answer 17

• DNA = adenine + guanine + cytosine + thymine
• DNA 2 strands of nucleotides that run antiparallel
• Linked by their nitrogenous bases
• RNA = adenine + guanine + cytosine + uracil
• RNA only has one strand