Understanding the Male Reproductive System
General Characteristics
Ontogenesis is a branch of biology that concerns the study of living beings from their fertilization until birth, also called embryology.
Reproduction is a fundamental characteristic of all living things, particularly humans, and has enabled and perpetuated evolution as biological species throughout the history of life.
Humans reproduce sexually, possessing gonads, organs specialized for producing gametes or sex cells. These unite to form the egg cell, called a zygote, from
Read MoreUnderstanding Mutation and Mutagenic Agents
Concept of Mutation
Mutation refers to any modifications or changes occurring in the genetic material that can lead to new manifestations of characteristics in organisms. The individual or cell carrying the mutation is called a mutant.
Key Features of Mutations:
- They are the source of new genetic characters and increase the genetic variability of organisms.
- They are heritable, persisting in the offspring when they occur in reproductive cells (germline mutations), transmitting the positive or negative
Monera, Protozoa, Algae, Fungi & Plant Nutrients: A Comprehensive Look
Monera: Microscopic Prokaryotes
Monera are microscopic, unicellular prokaryotes that reproduce asexually.
Eubacteria: Photosynthetic and Chemotrophic
Photosynthetic:
- Cyanobacteria with chlorophyll.
- Other bacteria with bacteriochlorophyll; photosynthesis without O2.
Chemotrophy: No light or O2 energy.
Heterotrophic Oxidation: Obtain nutrients from other sources, mostly saprophytic (fermentation), parasites, and symbionts causing diseases.
Archaebacteria
- Methanogens: Thrive in anaerobic, methane-rich environments.
Microbiology Terms: A Quick Reference
Here’s a list of key microbiology terms and their definitions:
- Agal: A polysaccharide extracted from seaweeds.
- Growth factors: Organic compounds required for growth that an organism cannot synthesize.
- Aerobic: Organisms that use oxygen as a hydrogen acceptor.
- Anaerobic: Organisms that use a hydrogen acceptor other than oxygen and are inhibited by oxygen.
- Aerobic Types:
- Aerobic Extrista: Organisms that only use oxygen as an acceptor.
- Microaerophilic: Organisms that require only small amounts of oxygen.
- Anaerobic
Animal Breathing: Types and Respiratory Processes
Usually, the inclusion of oxygen into an animal’s body is called breathing, but breathing encompasses three processes:
- Ventilation: Oxygen is taken from the environment and brought to the respiratory organ, and carbon dioxide is expelled.
- Gas Exchange: This occurs between respiratory organs and blood. The exchange takes place by diffusion, a process by which molecules pass from a more concentrated region to a less concentrated one without expenditure of energy. These regions are separated by a semipermeable
Cardiovascular and Lymphatic Systems: Diseases
Cardiovascular Diseases
Hypertension (High Blood Pressure): Blood pressure that exceeds normal ranges.
Arteriosclerosis: Hardening of the arteries and loss of elasticity; blood pressure rises, so hypertension may occur.
Atherosclerosis: Cholesterol plaque build-up in the internal walls of the arteries. This leads to the thickening of the affected area.
Aneurysm: Abnormal dilatation of a blood vessel, generally a main artery, which, when it ruptures, can cause death.
Varicose Veins: Abnormal dilatations