Biological elements

Elements

Different types of atom

How are elements distinguished

Elements are distinguished by the number of proton in their atomic nuclei.

all living things are made primarily from what four key elements

Carbon, Hydrogen, oxygen and nitrogen (N)

What are the additional elements that have important roles in the biochem of cells.

phosphorus and sulphur

4 Less important elements include:

sodium, Potassium, Calcium and iron.

Atoms connect with each other by forming […].

Atoms connect with each other by forming bonds.

When 2 or more atoms bond together the complex is called a […].

When 2 or more atoms bond together the complex is called a molecule.

How is a covalent bond formed

A covalent bond occurs when two atoms share a pair of electrons

 The electrons used to form bonds are unpaired and present in the […] of the atom.

 The electrons used to form bonds are unpaired and present in the outer orbitals of the atom.

How is bonding determined

Bonding is determined by the number of unpaired electrons present in the outer orbitals of different elements

- Carbon atoms can form […] bonds with other atoms.

- Nitrogen atoms can form […] bonds with other atoms.

- oxygen atoms con form […] bonds with other atoms.

- Hydrogen atoms can form only […] bond with another atom.

- Carbon atoms can form four bonds with other atoms.

- Nitrogen atoms can form three bonds with other atoms.

- oxygen atoms con form two bonds with other atoms.

- Hydrogen atoms can form only 1 bond with another atom.

What is Ion

 An atom or molecule in which the total no. of electrons is not equal to the total no. of proton is called an ion.

cation

If an atom or molecule loses 1 or More electrons it has a net positive charge

anion

If an atom or molecule gains electrons, it has a net negative Charge

 In ionic bonds, what happens

 In ionic bonds, one atom in the pair donates an electron and the other receives it.

→ This forms positive and negative ions that are held together by the attraction of the opposite charges.

Ions in solutions = […].

Ions in solutions = electrolytes.

Biological molecules all contain […].

Biological molecules all contain carbon.

Carbohydrates biological molecules

Carbon, hydrogen, and oxygen, usually in ratio Cx(H2O)x.

Lipids biological molecules

Carbon, hydrogen and oxygen

Proteins biological molecules

carbon, hydrogen, oxygen, nitrogen and Sulphur

Nucleic acids biological molecules

carbon, hydrogen, oxygen, nitrogen and phosphorus.

Polymers

Polymers are long-chain molecules made up by linking of multiple individual molecules (Monomers) in a repeating pattern.

In carbohydrates what are the monomers

In carbohydrates the monomers are sugars and in proteins the monomers are amino acids.