Human Biology: The Senses of Sight, Hearing, and Equilibrium

Sense of Sight

Vision is arguably one of the most important senses, as it provides us with the most information about our surroundings.

The structures related to vision are:

  • Accessory Structures
  • Eyeball
  • Optic Nerve
  • Brain

Accessory Structures

Eyelids

The upper and lower eyelids cover the eyes during sleep, protect them from excessive light and foreign matter, and spread lubricating secretions over the eyeballs.

Eyelashes and Eyebrows

Eyelashes arise from the edge of each eyelid and are composed of numerous

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Pharmacology Basics

Bioavailability refers to the extent a substance or drug becomes completely available to its intended biological destination(s).

The main function of progesterone is to prepare the endometrium (lining of the uterus) for a fertilized egg to implant and grow.

Agonist: A chemical substance that binds to and activates certain receptors on cells, causing a biological response.

Antagonist: A chemical substance that binds to and blocks the activation of certain receptors on cells, preventing a biological

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Classification of Environmental Hazards in the Workplace

Classification of Environmental Hazards

According to the way they interact with people, environmental hazards are classified as:

1. Chemical Hazards

These are represented by substances or chemicals that may be present in the workplace, depending on the production processes.

From the perspective of occupational hygiene, we can find them as gases or vapors and aerosols.

Causes of major diseases: asbestosis, systemic poisoning caused by the inhalation of dust or contact with organic chemical substances;

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Modern Biotechnology: Core Techniques & Recombinant DNA Technology

Two Core Techniques that Enabled the Birth of Modern Biotechnology

Genetic engineering: Techniques to alter the chemistry of genetic material (DNA and RNA) to introduce into host organisms and thus change the phenotype of the host organism.

Maintenance of sterile (microbial contamination-free) ambient chemical engineering processes: To enable the growth of only the desired microbe/eukaryotic cell in large quantities.

Conceptual Development of the Principle of Genetic Engineering

Asexual reproduction

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Plant Reproduction: Fertilization & Embryo Development

Prefertilization: Structure and Events

The Flower

Hormonal and structural changes in plants lead to the development of the flower.

The androecium consists of a whorl of stamens representing the male sex organ.

The gynoecium represents the female reproductive organ.

Stamen, Microsporangium, and Pollen Grain

A typical stamen consists of two parts:

  • A long and slender stalk called the filament
  • A terminal bilobed structure called the anther

A typical angiosperm anther is bilobed.

Each lobe has two thecae (dithecous)

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Respiratory Care of Infants and Children: A Comprehensive Guide

Cold Stress

Cold stress (body temperature <36°C or hypothermia) increases O2 consumption and can cause hypoglycemia, metabolic acidosis, apnea, pulmonary vascular hypertension, and increase right to left shunt. The smaller the infant, the higher the temperature needed to maintain the neutral thermal environment (NTE). The renal system is immature, which makes it difficult to compensate for ventilatory acid-base imbalance. Due to the immaturity of the renal system, the acid-base balance status

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