Understanding Genetic Mutations: Types and Causes
Mutations
Mutation refers to the sudden changes that appear in individuals of a plant species. Derived from an alteration that occurs in the sequence of nitrogenous bases of DNA, a sequence change in the amino acid is the corresponding protein. The protein encoded by that DNA can change its biological function or act inappropriately. We are now fully aware of the role that mutations play in numerous biological processes, from species evolution to the development of cancer.
Mutations can be classified
Read MoreLiver Cirrhosis, Hypertension, COPD, Hepatitis, Hemostasis: Causes & Symptoms
Cirrhosis
Cirrhosis is a chronic disease characterized by nodules and fibrosis in the liver.
Phases:
- Ascites
- Hepatic encephalopathy
- Hemorrhage
- Jaundice
Glisson’s capsule covers the liver. The cells that defend the liver are Kupffer cells. Initially, there is hepatomegaly and then the size of the liver reduces.
Symptoms:
- Vomiting
- Anorexia
- Abdominal pain (right upper quadrant) – Glisson’s capsule becomes inflamed
Signs:
- Clubbing (fingers with enlarged tips)
- Dupuytren’s contracture
- Growth of the parotid gland
- Peripheral
Cell Division, Biodiversity, and Supporting Tissues in Plants
Mitosis
Mitosis is the division of the nucleus. Before starting, the DNA is duplicated to have two identical copies of genetic information. Mitosis seeks to ensure each new nucleus receives a copy of this information.
Phases:
- Prophase: The DNA condenses and forms chromosomes. The cytoplasm is organized in a system of protein tubules, which are the spindle. At the end of prophase, the nuclear membrane disappears and the chromosomes are free in the cytoplasm. The nucleolus also disappears.
- Metaphase:
Plant Nutrition: Absorption and Transport of Water and Nutrients
**Thallophyte Organization**
Thallophyte organization refers to a type of organization where there are no tissues or organs, such as in algae and lichens.
**Cormophyte Organization**
Cormophyte organization refers to an organization in which cells are grouped into tissues and organs, such as in Pteridophytes and Spermatophytes.
Cormophytes have organs for nutrition:
- Roots: for absorption of water (H2O) and mineral salts.
- Leaves: for capturing light and atmospheric carbon dioxide (CO2).
- Conducting vessels:
Cell Division and Reproduction: Meiosis, Mitosis, and Gametogenesis
Estrogen
A female hormone that develops secondary sexual characteristics.
Gonads
A gland that produces male or female gametes: testes and ovaries.
Karyotype
The chromosomes of a cell or organism, characterized by the number, size, and configuration of chromosomes.
Cline
A gradient in the genotype or phenotype frequencies along a strip of a territory.
Sperm
Male gamete.
Egg
Female gamete.
Isogamic Reproduction
Type of sexual reproduction in which gametes are equal.
Heterogamic Reproduction
Mating type where gametes
Read MoreChromosomes, DNA Replication, and Genetic Processes
Chromosomes
Chromosomes are small, filamentous, rod-shaped structures that appear when a cell is dividing.
Parts of a Chromosome
- Chromatids: Two chromatids joined at the centromere form a chromosome.
- Telomeres: The terminal part of a chromosome, associated with aging and cellular senescence.
- Secondary Constriction and Satellites: Specific regions on some chromosomes.
Types of Chromosomes
- Metacentric: The centromere is in the center, and the two arms are equal.
- Submetacentric: The centromere is slightly