Lesson 5 - Biological elements Flashcards
Different types of atoms:
Elements
How are elements distinguished?
Number of protons in the atomic nuclei
Four key elements?
Hydrogen (H), Oxygen (O), Carbon (C), Nitrogen (N)
Two important elements below the 4?
Phosphorus (P) and Sulfur (S)
What other elements are important (4) in biochemistry?
Sodium (Na), Potassium (K), Calcium (Ca), Iron (Fe)
Covalent bonds
When two atoms share a pair of electrons.
Electrons shared in covalent bonding?
Unpaired and present in outer orbitals of the atoms.
Carbon atoms can form … bonds
4
Nitrogen atoms can form … bonds
3
Oxygen can form … bonds
2
Hydrogen can form … bond(s)
1
Draw Hydrogen (H2):
- Electron diagram
- Displayed formula
- ‘Ball and stick’ model
…
Draw water (H2O):
- Electron diagram
- Displayed formula
- ‘Ball and stick’ model
…
Draw Carbon Dioxide (CO2):
- Electron diagram
- Displayed formula
- ‘Ball and stick’ model
…
Draw methane (CH4):
- Electron diagram
- Displayed formula
- ‘Ball and stick’ model
…
Draw ammonia (NH4):
- Electron diagram
- Displayed formula
- ‘Ball and stick’ model
…
Ion
An atom or molecule in which the total number of electrons is not equal to the total number of protons.
Cation
Positive charge (loses an electron)
Anion
Negative charge (gains an electron)
Ionic bond
One atom in the pair donates an electron and the other receives it. This forms a positive and negative that are held together by the force of opposite charges.
Calcium ions formula
Ca (2+)
Sodium ions formula
Na (+)
Potassium ions formula
K (+)
Hydrogen ions formula
H (+)
Ammonium ions formula
NH4 (+)
Nitrate ions formula
NO3 (-)
Hydrogen carbonate ions formula
HCO3 (-)
Chloride ions formula
Cl (-)
Phosphate ions formula
PO4 (3-)
Hydroxide ions formula
OH (-)
Calcium ions are necessary for:
- Nerve impulse transmission
- Muscle contraction
Sodium ions are necessary for:
- Nerve impulse transmission
- Kidney function
Potassium ions are necessary for:
- Nerve impulse transmission
- Stomatal opening
Hydrogen ions are necessary for:
- Catalysis of reactions
- pH determination
Ammonium ions are necessary for:
- Production of nitrate ions by bacteria
Nitrate ions are necessary for:
- Nitrogen supply to plants for amino acid and protein formation
Hydrogen carbonate ions are necessary for:
- Maintenance of blood pH
Chloride ions are necessary for:
- Balance positive charge of sodium and potassium ions in cells
Phosphate ions are necessary for:
- Cell membrane formation
- Nucleic acid and ATP formation
- Bone formation
Hydroxide ions are necessary for:
- Catalysis of reactions
- pH determination
4 biological molecules:
- Carbohydrates
- Lipids
- Proteins
- Nucleic acids
Elements present in carbohydrates:
Carbon, Hydrogen, Oxygen
Ratio of Cx(H2O)x
Elements present in lipids:
Carbon, Hydrogen, Oxygen
Elements present in proteins:
Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur
Elements present in nucleic acids:
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus
Polymers
Long chain molecules made up by the linking of multiple individual molecules (called monomers) in a repeating pattern.
Carbohydrates:
Monomers and Polymers
Monomer: Monosaccharides
Polymer: Polysaccharides
Lipids:
Monomers and polymers
Monomer: Glycerol and fatty acids
Polymer: Triglycerides
Proteins
Monomers and polymers
Monomer: Amino acids
Polymer: Polypeptides
Nucleic acids
monomers and polymers
Monomer: Nucleotides
Polymer: DNA and RNA
