Introduction to Genetics: From DNA to Gene Expression
What is Genetics?
Genetics is the study of biological inheritance, genes, and their expression. Bateson and Johannsen proposed a set of concepts that formed the foundation of classical genetics, establishing conclusions such as:
- The unit of inheritance is called a gene.
- Genes are transmitted according to defined rules or laws.
- Genes are located on chromosomes.
- Sex is determined by genes or chromosomes in most living organisms.
Common Genetic Terms
- Genotype: The genetic constitution of an individual’s character
Understanding Cardiovascular Hemodynamics and Blood Pressure Regulation
Auricular Sinus Node (NSA)
Located on the upper wall of the right atrium at the mouth of the superior vena cava. Its specialized cells fire, self-excited, an electrical impulse that spreads through the atria via Bachman’s bundle, so that the two atria contract simultaneously.
Atrioventricular Node
Located at the junction between the two ventricles, consisting of specialized fibers. Its role is to delay the action potential.
Hemodynamics
Basic Theory of Circulatory Function
Blood flow depends on the nutritional
Read MoreHuman Digestive System: Mouth and Tongue Anatomy
Digestive System: The Mouth
Boca: The Gateway to Digestion
The boca, or mouth, is the first chamber of the gastrointestinal tract. It plays a crucial role in mastication (chewing) and salivation (saliva production). The mouth contains the tongue, which aids in digestion and speech (phonation).
The mouth consists of two cavities: the lobby, a horseshoe-shaped space above, separated from the top by arches, and the oral cavity, located behind the lobby.
Oral Cavity Anatomy
- Anterior Wall: Lips and cheeks
Newborn Assessment and Maternal Factors Influencing Neonatal Outcomes
Assessment of the Newborn: Chapter 2 – Maternal Factors
Maternal Factors
Any condition that leads to the interference with placental blood flow or the transfer of oxygen to the fetus can cause an adverse outcome.
Ultrasonography
Uses high-frequency sound waves to obtain a picture of the infant in utero. This allows the physician to:
- View the position of the fetus and placenta.
- Measure fetal growth.
- Identify possible anatomical anomalies.
- Qualitatively assess the amniotic fluid.
Amniocentesis
Involves direct
Read MoreThe Central Nervous System: Brain, Brainstem, and Spinal Cord
Hypothalamic-Hypophyseal Axis
Adenohypophyseal endocrine cells: Release adenohypophyseal hormones to the systemic circulation through the anterior hypophyseal veins.
Brainstem
External Morphology – Ventral View
The origins of cranial nerves III to XII can be observed.
Mesencephalon
- Cerebral peduncles: Connect the brainstem with the prosencephalon.
- Interpeduncular fossa: A depression.
Pons
- Pontocerebellar fascicles: Running transversally.
- Middle peduncles: Formed by pontocerebellar fibers.
Medulla Oblongata
- Olive:
Population Ecology and Ecosystem Dynamics
Population Ecology
Population and Growth
A population is a group of organisms of the same species capable of breeding with each other and occupying a given area. Population ecology studies the factors that regulate their dynamics and evolution over time.
Two opposing forces influence population growth:
- Biotic potential (r): The ability to reproduce.
- Environmental resistance: Factors that hinder growth.
The maximum number of individuals a population can support is called the carrying capacity or environmental
Read More