Workplace Hazards: Physical, Chemical, Biological, Organizational
Item 10. Risk Factors
1. Physical Hazards
These are different forms of energy that can affect those in their sphere of action, such as noise, vibration, lighting, thermal conditions, electrical hazards, and radiation.
a) Noise: Can damage the hearing apparatus and cause physiological and psychological effects. Noise is unwanted and annoying sound. Sound is an auditory sensation originating from a sound wave that comes from a vibration. The volume is measured in decibels (dB) and is determined by the
Read MoreKey Concepts in Genetics and Molecular Biology
Preformationism
In the 18th century, rudimentary microscopic observation of spermatozoa led to the belief that they contained tiny, fully formed humans called homunculi. It was thought that fertilization simply initiated the growth of these homunculi into individuals.
Epigenesis
With the development of the microscope, it became clear that fertilization involved not only growth but also a series of structural changes leading to the development of a complex organism.
Pangenesis
This theory proposed that
Read MoreDNA Structure, Function, and Amino Acid Properties
DNA: Structure and Function
DNA is a linear polymer composed of a pentose, a phosphate, and a nitrogenous base, which can be A, T, C, or G.
Primary Structure
The primary structure is the sequence of nucleotides linked by phosphodiester bonds. These links are established between the phosphate radical located in the 5′ carbon of one nucleotide and the OH radical in the 3′ carbon of the next nucleotide. A DNA strand has two free ends: the 5′ phosphate and the 3′ attached to a hydroxyl. These chains of
Read MoreHuman Genome: Understanding DNA, GMOs, and Genetic Diseases
Universal Statement on the Human Genome and Human Rights
The human genome is the basis of the fundamental unity of all members of the human family and the recognition of their inherent dignity and diversity. In a symbolic sense, the genome is the heritage of humanity.
- Each individual is entitled to respect for their dignity and rights, regardless of their characteristics.
- That dignity makes it imperative not to reduce individuals to their genetic characteristics and to respect the uniqueness of each
Human Biology: Nutrition, Cells, Tissues, Health, and Disease
Nutrition
Nutrition involves incorporating environmental matter and energy into cells to reproduce, replace damaged structures, and move. Waste products are urine and CO2. The following systems are involved: digestive, respiratory, circulatory, and excretory. Nutrition is not the same as digestion.
Organic Molecules
Organic molecules are made of atoms of carbon, oxygen, nitrogen, and phosphorus, and some contain sulfur. They can be very large and complex.
Inorganic Molecules
Inorganic molecules are much
Read MorePassive Immunity Transfer and Hypersensitivity Reactions in Animals
Passive Transfer of Immunity
A) Type of Placentation:
- Humans and Primates: Hemochorial placentation, maternal blood is in contact with the fetal trophoblast. There are only 2 layers of cells separating the maternal and fetal blood circulation. This allows the passage of IgG. At the time of birth, the newborn has an IgG titer similar to the mother’s.
- Dogs and Cats: Endotheliochorial placentation, the fetal chorionic epithelium is in contact with the endothelium of maternal capillaries. There are 3 cell