Health and Environmental Issues: A Comprehensive Guide

Air Pollution

The term “air pollution” is defined as the presence in the ambient (surrounding) atmosphere of s substances (e.g., gases, mixtures of gases and particulate matter) generated by the activities of man in concentrations that interfere with human health, safety or comfort, or injurious to vegetation and animals and other environmental media resulting in chemicals entering the food chain or being present in drinking-water and thereby constituting additional source of human exposure.


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Aquaculture Techniques: A Comprehensive Guide to Fish and Oyster Farming

Culture Facilities

Fish Farming


Enclosures designed to store and circulate water, enabling the confinement and rearing of fish. Ponds serve as artificial habitats that mimic natural environments, requiring farmers to manage feeding and health for optimal production.

Types of Ponds:
  1. Semi-natural: Existing bodies of water, often on clay soil to prevent leakage, modified for fish farming.
  2. Artificial: Purpose-built structures, either open pits or constructed with reinforced concrete (cement, brick,
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From Atoms to Organisms: Understanding the Building Blocks of Life

1. Formation of Living Organisms (Smallest to Largest)

1.1 Definitions

– Atom: The smallest structure, possessing positive, negative, and neutral charges.

– Chemical Elements: Groups of atoms, categorized as metallic or non-metallic (e.g., Hydrogen, Oxygen, Phosphorus).

– Molecule: A combination of elements (e.g., H2O, HCl).

– Macromolecule: Large molecules formed by combining smaller molecules (e.g., lipids, proteins, carbohydrates).

– Cell: The smallest structure capable of performing the three vital

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Evidence and Mechanisms of Evolution

Homologous Organs

The presence of organs with the same structural patterns but different functions in species that live in different environments is strong evidence of a common ancestor. These organs, called homologous organs, are the result of divergent evolution or adaptive radiation. Groups of individuals coming from the same species but living in different environments develop different functions or adaptations as a result of different selective pressures.

Vestigial Organs

Vestigial organs are

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Human Physiology: A Comprehensive Guide to the Body’s Functions

Renin-Angiotensin-Aldosterone System (RAAS)

The renin-angiotensin-aldosterone system (RAAS) is a system of hormones, proteins, enzymes, and reactions that regulate your blood pressure and blood volume on a long-term basis.

It regulates your blood pressure by increasing sodium (salt) reabsorption, water reabsorption (retention), and vascular tone (the degree to which your blood vessels constrict, or narrow). The RAAS consists of three major substances, including:

  • Renin (an enzyme)
  • Angiotensin II (a hormone)
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Human Anatomy and Physiology: A Comprehensive Guide to the Body’s Systems

Renin-angiotensin-aldosterone system (RAAS)

ECG (electrocardiogram)

Dental formula- I – 2/2 C – 1/1 P – 2/2 M – 3/3 = 16 x 2 = 32

The main components of the nephron are the glomerulus, the Bowman’s capsule or glomerular capsule, the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule.

Tidal volume is the amount of air that moves in or out of the lungs with each respiratory cycle.

Larynx is also known as voice box.

Lymph (clear, watery fluid) and lymphocytes (white blood cells)

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