Tooth Anatomy: Structure, Elements, and Eruption
Read MoreTeeth: A functional element of the stomatognathic system. They are hard, small bodies formed by different tissues. Teeth are arranged in arches, joined by jawbone tissue.
Functions: Chewing, phonetics, swallowing, aesthetics, preservation of bone.
Architectural Elements of the Tooth (Crown)
- Cusp: A pyramid-shaped structure with the base in the body of enamel. It is a peak in the chewing surface.
- Cingulum: An enlargement in the cervical third of the lingual surface of anterior teeth.
- Marginal Ridge: Convex
Bacterial Cell Structure, Types, and Reproduction
1. The Bacterial Cell (Prokaryote)
Most importantly, bacterial cells have no nucleus and are smaller and more primitive than Eukaryotic cells. They have no cells or tissues, or higher organizations.
It has 3 parts:
The Shell
A bacterium can have 3 envelopes:
- Capsule: The outermost envelope of bacteria, with variable sizes depending on the species. It has a mucous appearance and functions to provide resistance to environmental dryness. This wrapper does not appear in all species.
- Bacterial Wall: Found
Cell Theory, Biology, and Human Body Processes
Key Figures and Discoveries in Biology
Schleiden and Schwann authored the cell theory. Jansen is associated with the microscope, while Knoll and Ruska developed the electron microscope. The scientific method is based on facts, logic, and order. Carolus Linnaeus developed Systema Naturae and is a key figure in taxonomy.
Branches of Biology
- Anatomy: The study of the structure of living things.
- Physiology: Studies the functioning of organisms.
- Genetics: Deals with the study of the transmission of hereditary
Understanding Your Body’s Defenses: Immunity Explained
1. Body’s Defense Mechanisms
1.1 External Barriers
1.1.1 Physical Barriers
Skin: Infectious organisms can only penetrate the body when the skin is injured. Therefore, it is important to clean and disinfect any wound with soap and iodine solution.
1.1.2 Chemical Barriers
There are different parts of our body where there is no skin, such as the mouth, nostrils, eyes, anus, urethra, and vagina. The mucous lining of these parts secretes substances that kill microorganisms, such as lysozyme.
Lysozyme is an
Read MoreSensory Transduction: Olfactory, Gustatory, and Visual Systems
Sensory Transduction Mechanisms
Vestibular System
- Head movements cause stereocilia to move in the opposite direction of head rotation.
- Neurotransmitter release at the synapse between vestibular hair cells and the afferent neuron involves glutamate.
- Afferent nerve fibers in the inner ear converge to form the vestibulocochlear nerve.
- Meniere’s disease can cause dizziness.
Olfactory System
- The olfactory membrane is located within the nasal conchae.
- Odorant receptors are G-protein coupled receptors.
- Olfactory
Nutrition and Nutrients: Essential Guide to a Balanced Diet
Nutrition and Nutrients
Nutrition: A set of processes through which the body receives, transforms, and incorporates needed nutrients.
Nutrients: Chemical compounds contained in foods that cells need to live.
Duties of Nutrients:
- Energy: Invigorating.
- Plastic and Reconstructive: Contributing components to growth.
- Regulator: Substances that control chemical reactions.
Types of Nutrients
- Carbohydrates: They provide a lot of energy. Some are simple and easy to digest, while others are more complex.
- Lipids: Develop.