Decoding DNA: Genetics, Experiments, and Molecular Structure
DNA (Deoxyribonucleic Acid): The genetic material that carries hereditary information. The central dogma of molecular biology is DNA → RNA → Proteins. These proteins, often polypeptides, form structures like enzymes, which participate in the formation and breakdown of biomolecules, including nucleic acids, lipids, carbohydrates, and proteins.
RNA (Ribonucleic Acid): Another type of nucleic acid essential for various biological roles.
Genotype: The genetic information of an organism.
Phenotype:
Read MoreCell Division: Understanding Mitosis and Meiosis
Mitosis
- Interphase: Visible nucleolus, chromosomes or diffuse chromatin.
- Prophase: Nucleolus disappears. Centrioles and asters appear and separate. The spindle forms, and each chromosome that constitutes two chromatids reappears together by the centromere.
- Metaphase: The nuclear membrane disappears, and the spindle extends to the poles. Chromosomes align on the spindle.
- Anaphase: Each centromere divides. Sister chromatids separate and go to opposite poles. The separated chromatids are now considered
White Blood Cells, Hemostasis, and Heart Sounds Explained
White Blood Cells (WBCs)
WBCs are an important part of the immune system, defending the body against infections and foreign invaders. They are classified based on function and production process in bone marrow.
Types of White Blood Cells
Granulocytes
Neutrophils
- Function: Primary defense against bacterial infections. Phagocytic cells ingest and destroy pathogens.
- Production: In bone marrow.
Eosinophils
- Function: Defend against parasitic infections and are involved in allergic reactions. Help modulate inflammatory
Understanding Genetics: DNA, Genes, and Engineering
Stem Cells
Stem cells retain the ability to renew themselves through self-division. They can differentiate into a range of specialized pluripotent cells, retaining the ability to change into other cells.
Inherited vs. Acquired Characteristics
Inherited variations are received from genes from your parents. Acquired variations are not present at birth; you learn or acquire them throughout your life.
DNA Structure
Deoxyribonucleic acid (DNA) is hereditary material that carries and passes on genetic information.
Read MoreMollusks and Arthropods: Characteristics and Classification
Mollusks: Characteristics and Classification
Mollusks are invertebrates of great importance to humans, providing food and materials for jewelry, among other things. A negative aspect is that some can cause schistosomiasis.
Mollusk Classification
- Monoplacophora: Single shell, found in deep-sea environments.
- Polyplacophora: Shell composed of eight plates, marine.
- Scaphopoda: Conical shell, buried in the seabed sand.
- Gastropoda: May have no shell or a single shell; the most numerous and diverse group (
Characteristics of Life and Cellular Organization
Characteristics of Life
Key characteristics define living organisms:
- Movement: Ability to change position or move internally.
- Responsiveness: Reaction to internal and external changes.
- Growth: Increase in size without changing shape.
- Reproduction: Production of new organisms and new cells.
- Respiration: Obtaining oxygen, removing carbon dioxide, and releasing energy from foods.
- Digestion: Breakdown of food substances into simpler forms.
- Absorption: Movement of substances through membranes and into body fluids.