Grade 10 Biology TEST on Molecular Biology and Human nutrition Flashcards
4 Main Biological Molecules
Carbohydrates (energy containing molecules)
Proteins (energy containing molecules)
Lipids (energy containing molecules)
Nucleic acid (DNA, RNA)
Carbohydrates
Monosaccharides: ex - glucose
Disaccharides: ex - sucrose
Polysaccharides: ex - starch
Elements of Carbohydrates
Carbon (1), Hydrogen (2), Oxygen (1)
- Most carbohydrates have this ratio.
Glucose structure
6 siding:
- carbon atom: 4 bonds
- oxygen atom: 2 bonds
- hydrogen atom: 1 bond
- nitrogen atom: 3 bonds
*go to notebook
Starch
Carbohydrate made by plants (stored in the chloroplast) for energy storage
Glycogen
Carbohydrate made by animals for energy storage
Element in protein but not carbs or fats.
Nitrogen and sulfur
Amino acids
Small molecules to join protein molecules together.
Protein examples
Keratin, collagen and elastin
What determines the number of covalent bonds that an atom can form?
The number of electrons required to fill the valence shell.
Monosaccharides
(single sugars)
- Glucose (C6H1206)
- Fructose (C6H1206)
- Galactose (C6H1206)
- Ribose (Help us produce RNA and DNA)
- Deoxyribose (Help us produce RNA and DNA)
Most important monosaccharide
6CO2 + 6H2O → C6H12O6 + 6O2
Photosynthesis
How do we produce the disaccharide Maltose by joining two glucoses?
*go to notebook
What have we done?
- Condensation reaction
- A water molecule is produced
- Glucose + Glucose –> Maltose + Water
- An enzyme is required
- An ATP molecule is required
What are other disaccharides?
- Glucose + Fructose –> Sucrose
- Glucose + Galactose –> Lactose
How do we make a polysaccharide?
Continue to add glucoses by conducting additional condensation reactions.
*go to notebook
Starch to Glycogen
Eat starch (pasta) – digest – glucose in blood – excess glucose – converted to glycogen (by the liver and the muscles, over time glycogen is converted back to glucose).
- glucose is used by cells to make ATP.
Proteins
Carbon, hydrogen, oxygen, nitrogen, sulfur (CHONS)
- proteins are long single-chained polymers of amino acids.
- allow your body to develop and grow by repaired body cells and works as structural support
What is the structure of the amino acid?
*go to notebook
20 different types of amino acids.
Standard structure: carboxyl group, amino group and central C with H.
- R group/side chain/radical group
- Amino (NH2 - Ammonia) group
- Carboxyl group/COOH group/organic acid group
Why is it called carboxyl group?
All organic products have carbon, oxygen and hydrogen.
Why is it called organic ACID group?
H separates from the O leaving an H+ and 0- (disassociation)
Which feature is different from one amino acid to the next?
The R group (20 different R groups)
In what ways can R groups differ?
These factors determine the structure (determines/affects its function) of the protein (rich amino acids are present in the proteins and the specific sequence of the amino acid in the chain).
- size (small or big)
- hydrophobic (water hating - repels: less soluble in water)
- hydrophilic (water loving: more soluble in water)
- Acidic or alkaline
- positively or negatively charged
- contain sulfur or not (2 of 20 do not)
Connecting two amino acids together
*go to notebook
creates a peptide bond
- when we produce protein we are connecting amino acids
Two amino acids are joined by a covalent bond to form a dipeptide.
Characteristics of connecting two amino acids together
- condensation reaction
- water is produced
- amino acid + amino acid –> dipeptide + water
- enzyme (in the ribosome) is required
- ATP is required
Mouth, oesophagus and stomach
when food is chewed, the tongue mixes the food with saliva, which contains mucus (a slimy substance that lubricates the passage of the food bolus down the throat). when food is swallowed, it squeezes pst your epiglottis into your oesophagus.
Stomach digestive juice
gastric juice
- protease produced by the the walls of the stomach is called pepsin.
- starts the digestion of proteins to smaller molecules called polypeptides.
Amylase
breaks down starches and carbohydrates into sugars.
Protease
breaks down proteins into amino acids.
Lipase
breaks down lipids, fats and oils, into glycerol and fatty acids.
Functions of proteins
- movement (muscle): actin and myosin
- transports: hemoglobin transports O2
- catalyzing chemical reactions: enzymes (catalase)
- structure: keratin and collagen
- defense (against pathogens): antibodies
- communication (within the body): hormones and neurotransmitters (there are some that are not proteins)