The Vital Functions and Biomolecules: Building Blocks of Life
The Vital Functions
- Nutrition Function: The process by which living beings obtain the matter and energy necessary for life.
- Interaction Function: The process by which living things relate to their surrounding environment.
- Reproduction Function: The process by which new individual living beings are reproduced.
- Sexual: Requires a male and a female parent.
- Asexual: Requires only one parent.
Biomolecules
Biomolecules are the building blocks of life. They are mainly composed of carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus. Organic biomolecules are exclusive to living beings.
Types of Biomolecules
- Carbohydrates: The most abundant biomolecules, also called saccharides. They are made up of monosaccharides and are responsible for storing and transporting energy. They are also structural components. Examples: Glucose, fructose, cellulose
- Lipids: Organic compounds that occur naturally and are insoluble in water. Fats and oils are used for storing energy. Phospholipids are fundamental in the structure of cell membranes. Steroids act as sexual hormones. Waxes give protection.
- Proteins: Macromolecules with complex structures, which are made up of chains of smaller amino acids. Their most important functions are to give structure to cells, transport substances around the body, regulate chemical reactions, and protect the body from bacteria and microorganisms.
- Nucleic Acids: Macromolecules which are formed by the union of smaller molecules known as nucleotides. Nucleic acids are found in the genetic material of cells.
- Deoxyribonucleic acid (DNA): Stores all the information necessary for the functioning and development of living things. It is found in the cell nucleus and makes up the genetic code.
- Ribonucleic acid (RNA): Participates in the synthesis of proteins. It is found in the cytoplasm.
Inorganic Biomolecules
Inorganic biomolecules are compounds that are not exclusive to living beings.
- Water: The most abundant inorganic biomolecule. It is present in tissues, organs, blood, and even in your teeth. It is used to carry out all chemical reactions, transport substances, and regulate body temperature.
- Mineral Salts: Form the solid structure of living beings, such as skeletons. They are involved in chemical reactions and are necessary for the transmission of nervous impulses.
Cells
Cells are the structural and functional units of living beings. They have three basic structures:
- Cell Membrane: The thin layer which separates the inside of the cell from its surrounding environment.
- Cytoplasm: Contains structures called organelles, which are responsible for cell functions. It is a gelatious, semi-transparent fluid.
- Nucleus: Carries the genetic information of living things which is passed from one generation to the next.
Types of Cells
- Animal Cell: Cell membrane, nucleus, rough ER, vacuoles, vesicles, cytoplasm, mitochondrion, and Golgi body
- Plant Cell: Cell membrane, nucleus, rough ER, vacuoles, vesicles, cytoplasm, mitochondrion, Golgi body, cell wall, and chloroplast
Eukaryotic and Prokaryotic Cells
- Eukaryotic Cells: The genetic material is enclosed in a structure called the nucleus. Animals and plants are multicellular, eukaryotic organisms.
- Prokaryotic Cells: The genetic material is closed in the cytoplasm. Bacteria are unicellular, prokaryotic organisms.
Cellular Nutrition
Cellular nutrition consists of all the processes in which cells obtain matter and energy to perform vital functions. Nutrients are obtained from food. Once inside the cell, the nutrients are subjected to chemical processes called cellular metabolism.
- Catabolism: The degradation of complex organic substances into simple substances. It produces energy.
- Anabolism: The production of more complex organic substances from simple substances. It requires energy from catabolism.
Autotrophic and Heterotrophic Nutrition
- Autotrophic: Characteristic of cells which use an energy source to make their own organic matter from inorganic matter. Two processes depending on the energy source:
- Photosynthesis: Energy comes from the sun
- Chemosynthesis: Energy comes from chemical reactions
- Heterotrophic: Characteristic of cells which feed on organic matter produced by other living beings. They transform this organic matter to obtain nutrients and energy.
Cellular Respiration
Respiration is the release of energy from organic substances into living cells. All cells need energy to carry out the vital functions.
Cellular respiration describes the metabolic reactions and processes which take place in a cell to obtain chemical energy from specific organic molecules. First, the cell takes in organic substances and oxygen. Then, it breaks down those substances into simpler substances, such as carbon dioxide and water. At the same time, energy is released.
Fermentation is the process by which cells release energy in the absence of oxygen.
Cellular Division
Cellular division is a process by which a cell, parent cell, divides into two or more cells, called daughter cells.
In unicellular organisms, cellular division replicates an entire organism and new individuals are formed. As a result, there is an increase in the population.
Types of Cellular Division
- Binary Fission: First, the nucleus of the parent cell divides into two identical nuclei. Then the parent cell divides into two identical daughter cells of the same size.
- Multiple Fission: The nucleus of the parent cell divides into several nuclei. After the nuclear divisions are complete, the cytoplasm separates. Then each nucleus becomes encased in its own membrane to form an individual cell.
In pluricellular organisms, cellular division results in an increase in the number of cells of an organism. This increase is reflected in the growth or repair of damaged parts of the organism.
Kingdoms of Life
- Kingdom Monera: A moneran has only one cell. It has no nucleus. Monerans can make their own food. Example: Bacteria
- Kingdom Protista: Some protists have one cell. Their cells always have nuclei. If a living thing has a cell with a nucleus, but it is not a plant, an animal, or a fungus, it is a protist. Example: Amoeba
- Kingdom Fungi: Fungi have more than one cell and their cells have nuclei. Their cells also have a cell wall made from chitin. Fungi cannot make their own food. Examples: Mushrooms and mold
- Kingdom Plantae: Plants have more than one cell and their cells have nuclei. Their cells also have a cell wall made from cellulose. Examples: Flowers and trees
- Kingdom Animalia: Animals have more than one cell and their cells have nuclei. Animals cannot make their own food. Examples: Sponges, insects, fish, birds, and humans