General Knowledge: Atomic Structure

Study Notes

Atom Bonding and Electrons

Elements bond to achieve stability through electron sharing or transfer.
Neutral atoms and positively charged atoms are located in the nucleus, while negatively charged electrons orbit around it.
Electrons follow the octet rule, filling electron shells in the pattern of 2, 8, 8.
Valence electrons, like 8e in the outer shell, are crucial for chemical bonding.
A shared pair of electrons forms a covalent bond.

The Big 4 Biomolecules

Carbohydrates

Composed of carbon, hydrogen, and oxygen with a ratio of 1:2:1.
Serve primarily for short-term energy storage.
Monomer: Monosaccharides (simple sugars) like glucose (C6H12O6).
Polymers consist of long chains of glucose; hexagonal structures indicate glucose.
Classic examples include starch in plants and glycogen in animals.
Structural roles: Cellulose (cell walls) and chitin (exoskeletons).

Lipids

Made up of carbon, hydrogen, and oxygen, but not in a 1:2:1 ratio.
Do not have monomers; built from a glycerol backbone and up to three fatty acid tails.
Known for long-term energy storage, providing 9 calories per gram (versus carbohydrates at 4 calories per gram).
Functions include insulation, protection, energy storage, nutrient absorption, and hormone production.
Main components of cell membranes.
Common examples: Fats (saturated and unsaturated), oils, phospholipids, waxes, blubber, and steroids.

Proteins

Composed of carbon, hydrogen, oxygen, nitrogen, and sulfur (CHONS).
Monomers are amino acids, characterized by an amino group (NH2) and a carboxyl group (COOH).
Proteins are polymers known as polypeptides.
Functions of proteins include:
- Enzymes that regulate chemical reactions.
- Antibodies that support the immune system.
- Structural roles in cells, muscles, and fibers (e.g., hair and nails).

Nucleic Acids

Contain carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHONP).
Monomers: Nucleotides, which include a sugar, phosphate group, and nitrogenous base.
Polymers include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).
Functions:
- DNA serves as hereditary material and is fundamental for genetics.
- RNA is crucial for protein synthesis.

Description

Test your understanding of atomic structure and the behavior of elements as they bond to achieve stability. This quiz covers key concepts such as neutral atoms, electron arrangement, and the octet rule. Challenge yourself to remember how electrons fill orbitals and the implications of these interactions.