Fundamentals of Life Sciences, Atoms, and Biomolecules
Life Sciences
Genetic (biological inheritance laws and the variation), Cytology (structure and functioning of cells), Histology (tissue structure), Botanica (algal photosynthesis, plants, and some bacteria), Zoology (animals in their development and interaction with the environment), Anatomy (macroscopic structures that form the body of living organisms such as organs and organ systems), Embryology (the development of organisms from zygote to the characteristics of the adult organism), Biochemistry (chemical properties of cells), Ecology (relationships of living beings between them and the environment), Taxonomy (classification of natural living organisms), Paleontology (fossils).
Atoms
Atoms are basic structural units of matter. Atoms are composed of a central atomic nucleus. The nucleus contains protons (positively charged), neutrons (no charge), and electrons (negative charge).
- Atomic number: The number of protons in the nucleus.
- Isotope: One of several forms of an element whose nucleus contains equal numbers of protons and different neutrons.
- Element: A substance that cannot be decomposed or converted into another substance by chemical processes.
- Chemical bonds: Attractive force that holds atoms in the molecule.
- Ionic bond: Bond in which atoms lose or gain electrons to balance the protons and electrons.
- Covalent bonds: The bond in which atoms share electrons between them.
Carbohydrates
Carbohydrates are molecules made up of carbon, hydrogen, and oxygen. All are water-soluble. Sugars such as starch (1 sugar = monosaccharide; 2 sugars = disaccharide). Examples: glucose, fructose, sucrose. These contain much energy.
Lipids
Lipids have enough carbon and hydrogen and are water-insoluble molecules. Their stored energy is divided into: 1. Oils, fats, and waxes; 2. Phospholipids; and 3. Steroids.
Characteristics of Living Things
- Living things are composed of cells that have a complex and organized structure.
- Living things respond to stimuli in their environment.
- Living things actively maintain their complex structure and its internal environment.
- Living things obtain and use materials and energy from their environment.
- Living things grow.
- Living things reproduce.
- Living things evolve.
Water
Polar substances: amino acids; Nonpolar substances: oil, gas, O-CO2. The polarity of water is due to hydrogen (H). These are weak bonds, where the region is a positively charged H atom. The polarity of water and hydrogen bonds allow you to maintain 3 physical states.
- Cohesion: The tendency of molecules to stick together. In the water, it is stronger than other liquids and thanks to bridges of H.
- Surface Tension: A measure relating to how hard it is to break the surface of a liquid. Closely related to cohesion. The hydrogen bonds give water tension and make it behave as if covered by an invisible film.
- Buffers: Regulate the pH. Types H2CO3 (H is given to water to lower the pH) and HCO3 (accept H ions).
Water has resistance to temperature changes through the links on H. Thanks to this, water on the planet moderates the temperature, maintaining life. Heat is not the same as temperature.
- Heat: Energy associated with the motion of atoms and molecules in water.
- Temperature: Refers to the average of the molecules rather than the total amount of heat energy in the water body.
Proteins
A protein is composed of amino acids, carbon, hydrogen, oxygen, nitrogen, and sulfur. Polypeptides are long chains of amino acids. Examples: keratin, silk, and hemoglobin.
Nucleic Acids
Nucleic acids are formed by nucleotides, carbon, hydrogen, oxygen, and phosphorus. All have a five-carbon sugar, a phosphate, and a nitrogenous base. Examples: DNA and RNA. AT and CG.