Genetics and Heredity: Key Concepts and Principles

1. Genetics Basics: Fill in the Blanks

  • (a) The total number of chromosomes in a human cell is 46.
  • (b) Phenylketonuria causes mental retardation or brain damage.
  • (c) Genetic disorder due to the presence of an additional X-chromosome is Klinefelter’s syndrome.
  • (d) The genetic constitution of an organism is called a genotype.
  • (e) August Weismann proposed that nuclei are the bearers of hereditary characters.
  • (f) Gregor Mendel is known as the father of genetics.

2. Fundamental Genetic Definitions

What is a

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Principles of Organic Evolution and Origin of Life

1. Fundamentals of Evolutionary Biology

1. How can you determine the age of a fossil?
The age of a fossil is determined by radiocarbon (C-14) dating.

2. What is a protovirus?
A protovirus is viral DNA integrated into the genome of a host cell.

3. What were the raw materials used in Miller’s experiment?
The raw materials were methane, ammonia, hydrogen, and water vapour.

4. What is hidden hunger?
Hidden hunger is a condition caused by a deficiency of essential vitamins and minerals in the diet.

5. How are

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Viral Persistence, Latency, and Immune Evasion Mechanisms

Defective-Interfering Particles and Persistent Infection

1. How do defective-interfering (DI) particles contribute to persistent infections?

Defective-interfering (DI) particles are incomplete viruses that lack essential genes for full replication. They replicate only in the presence of a normal virus and compete with it for cellular resources. This reduces viral replication and cytopathic effects, allowing infected cells to survive and the virus to persist long-term.

Viral Nucleic Acid Sensing by

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Echinodermata Biology: Characteristics and Classification

General Characteristics of Phylum Echinodermata

Phylum Echinodermata (from Greek echinos = spiny; derma = skin) consists of exclusively marine animals known for their pentamerous radial symmetry and unique water-driven skeletal systems.

  • Habitat: Entirely marine; found at all depths from the intertidal zone to the deep sea.
  • Symmetry: Adults exhibit pentamerous radial symmetry (body parts arranged in fives), while larvae are bilaterally symmetrical.
  • Body Organization: Triploblastic, coelomate, and exhibit
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Human Anatomy and Physiology: Key Systems, Fluids, and Processes

Nervous System

Nervous system: The nervous system is the most complex system of the human body, containing a vast network of nerve cells. It is the major controlling, coordinating, regulatory and communicating system of the body. The nervous system is the body’s command centre and the centre of all mental activities including thought, learning, and memory. It is also responsible for maintaining homeostasis.

Organization of the Nervous System

  • Central Nervous System: Brain, Spinal cord
  • Peripheral Nervous
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Molecular Biology Essentials: DNA Structure, Replication, and Protein Synthesis

1. DNA Structure

      • Double Helix: Twisted-ladder shape.

      • Nucleotide: Sugar (deoxyribose) + Phosphate + Nitrogenous base.

      • Bases: Purines (Adenine [A], Guanine [G]); Pyrimidines (Cytosine [C], Thymine [T]).

      • Pairing: A pairs with T (2 Hydrogen bonds), C pairs with G (3 Hydrogen bonds).

      • Chargaff’s Rule: A = T, and C = G.

      • Antiparallel Strands: Run in opposite directions (5’→3′ and 3’→5′).

Key Scientists

      • Griffith: Discovered the transforming factor.

      • Avery: Identified DNA as the transforming factor.

      • Chargaff:

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