Rhesus Blood Groups and Maternal-Fetal RhD Incompatibility

Rhesus Blood Groups and RhD Incompatibility

Rhesus Blood Group System

  • Genetically determined by 6 important antigens (among approximately 50 antigens): c-C, d-D, e-E.
  • Presence of antigen D (a strong antigen) on the erythrocyte membrane determines positivity (Rh+). This applies to about 85% of the European population.
    • Possible Genotypes: CDE, CDe, cDe, cDE
  • Rh negativity (Rh-) is determined by the d antigen (a weak antigen).
    • Possible Genotypes: Cde, Cde, cde, cdE
  • Sometimes, the presence of the E antigen
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Nervous System Function: Autonomic Control & Neural Signals

Nervous System Organization

The Nervous System comprises two main parts:

  • Central Nervous System (CNS): Consists of the brain and spinal cord. It builds and maintains models of the environment, makes decisions, and processes sensory information. Grey matter contains dendrites and cell bodies, while white matter consists of myelinated axons. The blood-brain barrier tightly regulates substances entering the brain.
  • Peripheral Nervous System (PNS): Includes all neural tissue outside the CNS, connecting
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Fundamentals of Biology: Energy, Atoms, Molecules, and Systems

Energy and Its Forms

Energy is the ability to cause changes. There are two kinds:

  • Potential Energy: Unactualized energy.
  • Kinetic Energy: Active energy. Examples include heat, electricity, light, and movement. Potential energy includes gravity and chemical energy.

Atoms and Molecules

Atoms are the smallest unit of an element (e.g., Oxygen, Hydrogen, Nitrogen, Carbon, Iron).

Subatomic Particles and Molecules

Subatomic Particles (protons, neutrons, and electrons) together make up atoms, which form molecules.

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Key Biological Processes and Concepts Explained

Key Biological Processes

Transcription, Translation, and Translocation

Transcription: The process of RNA synthesis.

Translation: Amino acids are supplied by tRNA according to the message on mRNA. tRNA has an ‘anticodon’ with a complementary sequence to the codon on mRNA.

Translocation: The ribosome moves along the mRNA by the distance of one triplet codon.

Central Dogma: The process of protein synthesis from DNA through RNA.


Important Biological Molecules

NAD: Nicotinamide Adenine Dinucleotide

FAD: Flavin

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Understanding the Excretory and Urinary Systems: Functions and Anatomy

The Excretory System: An Overview

The excretory system comprises the urinary system and other organs and systems that aid in waste product excretion.

Other Components of the Excretory System

  • Respiratory System: Removes carbon dioxide from the blood and expels it from the body.
  • Sweat Glands: Located in the skin, these glands produce sweat, which evaporates to cool the skin. Some excretory substances are also eliminated through sweat.
  • Liver: Eliminates products from the breakdown of hemoglobin from old
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Cilia: Structure, Function, and Movement Mechanisms

Cilia: Structure, Function, and Movement

Cilia are mobile cytoplasmic extensions, typically 5 to 10 μm in length and 0.2 μm thick. They contain an axoneme and project from the free surface of many cells. Cilia function to move crawling or rolling particles, agitate and circulate fluids across surface epithelia, such as in the respiratory tract and certain excretory tubes of the testis.

Cilia originate from basal corpuscles. Structurally, a cilium is composed of the axoneme and ciliary membrane,

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