Sensory 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.
Human Biology: Blood, Excretion, Nutrition, and More
Human Biology: An Overview
Blood Composition and Function
Blood is composed of plasma and three types of cells:
- Erythrocytes: Red blood cells without a nucleus, responsible for oxygen transport.
- Leukocytes: White blood cells that defend the body against infections.
- Platelets: Involved in blood coagulation.
Diastole refers to the relaxation of the heart chambers, while systole refers to their contraction.
Excretion and the Kidneys
Excretion is the process of eliminating waste substances from the blood.
The
Read MoreDarwinian Evolution: Natural Selection, Speciation, and Mechanisms
Lesson 1: Darwin and Natural Selection
Evidence for Evolution:
- Selection is a plausible mechanism for species change.
- The fossil record shows species change over time (e.g., whale hind legs).
- Homology of forelimb structure and comparative embryology suggest common ancestry.
- Biogeography showed patterns of distribution of organisms consistent with ancestor-descendant relationships (e.g., beak sizes).
Evolution of drug resistance and viruses is important to our health and society.
The State of Knowledge
Read MoreMolecular Biology: DNA Transcription, Translation, and Genetics
DNA Transcription and RNA Synthesis
During transcription, an RNA molecule, called messenger RNA (mRNA), is synthesized. This mRNA is complementary to the DNA fragment that carries the information for a specific protein. This molecule provides the information necessary for ribosomal protein synthesis. Cells produce proteins, such as enzymes and structural proteins, that may not always be needed. This can lead to a progressive deterioration of cellular functions and activities.
Peptide Mutations
a) AAT
Read MoreJoint and Muscle Proprioceptors: Types and Movements
Anatomical Classification of Joints
Based on the tissue that is located between joint surfaces. Types:
- Syndesmosis: A union made of fibrous connective tissue or dense fibrous elastic tissue. Examples of dense fibrous tissue are the interosseous membranes that unite the diaphyses of the two bones of the forearm and leg. An example of binding elastic tissue are the yellow ligaments that join the vertebral arches to each other.
- Synchondrosis: Here the tissue is hyaline cartilage. As an example, we have