Structure and Function of the Cell Nucleus
Nucellus in Interface
Presents nuclear envelope and developed chromatin fibers. The core has a very active K and occurs for later transcription translation. Also, before division occurs, DNA duplication takes place. We also find the nucleoplasm and the nucleolus or nucleoli. When the nucleus is in division, it presents some major changes. The condensed chromatin fibers give rise to structures called chromosomes. Then, the nuclear envelope will also change. In this way, the chromosomes remain immersed
Read MoreGene Expression and Protein Synthesis Essentials
Genetic Code Essentials
The genetic code defines the relationship between nucleotide triplets (codons) and amino acids (AA). It operates in the 5′ to 3′ direction. Most codons are synonymous, meaning multiple codons can code for the same amino acid. There are 64 possible codons, with 61 coding for amino acids.
Regulation of Gene Expression
Cells regulate gene expression to control when proteins are produced.
DNA Replication
DNA replication is the process of duplicating DNA in each cell generation. It
Read MoreThe Origin and Evolution of Life and Humans
The Origin and Evolution of Life
Early Hypotheses
The earliest explanation for the origin of life attributed it to a higher being creating Earth and all life. The panspermia hypothesis proposed that meteorites containing organic molecules seeded life on Earth, but it didn’t explain the origin of these molecules or how they survived space. Arrhenius, a proponent of this idea, believed that organic molecules were essential for life, but later discoveries showed that organic molecules don’t necessarily
Read MoreCellular Respiration, Meiosis, Genetics, and Cell Structure
Cellular Respiration
C6H12O6 + 6O2 → 6CO2 + 6H2O
Aerobic Respiration: A process of glucose degradation where oxygen is the final electron and proton acceptor. Glycolysis: C6H12O6 → 2 pyruvate. Pyruvate enters the mitochondria and is transformed, producing CO2, protons, and electrons. Electrons and protons move along the cristae until they reach O2, forming water. ATP is generated through this process.
Aerobic Respiration Equation: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP
Meiosis
Meiosis is the process
Read MoreFlatworms, Roundworms, and Plant Structures
Platyhelminthes (Flatworms)
Introduction – Flatworms have bilateral symmetry.
Bilateral Symmetry – Symmetry that divides the body of a living being into two equal parts from a longitudinal section.
Habitat – Flatworms are found in:
- Wet soil – Geoplana
- Freshwater – Dugesia
- Saltwater – Notoplana and Stylochus
- Inside living organisms, as parasites – Taenia, Schistosoma, Fasciola
Structure – Flatworms are elongated animals with a flattened dorsoventral body, segmented or unsegmented. They have digestive and
Read MoreInfectious and Non-Infectious Diseases: An Overview
Infectious Diseases
Infectious diseases originate from the colonization of the body by infectious agents or vermin infestation.
Routes of Transmission
Infectious agents can be transmitted from a sick individual through:
- Direct Contagion: Occurs from person to person.
- Indirect Contagion: Transmission through various mediums:
- Air: Microorganisms from a sick person pass to a healthy person through coughing or sneezing, transmitting respiratory diseases like tuberculosis.
- Water: A significant transmission