What does DNA stand for?
Deoxyribonucleic acid
DNA stores hereditary information organized into chromosomes wrapped around histone proteins.
What is the molecular structure of DNA?
Double helix formed by two complementary strands
Base pairing: A ↔ T, G ↔ C.
What is the central dogma of molecular biology?
DNA → transcription → RNA → translation → proteins
This describes the flow of genetic information.
Compare the strands of DNA and RNA.
- DNA: Double‑stranded
- RNA: Single‑stranded
This structural difference affects their functions.
What type of sugar is found in DNA?
Deoxyribose
RNA contains ribose.
What are the bases found in DNA?
- A
- G
- C
- T
RNA contains A, G, C, U.
What is the primary function of DNA?
Genetic storage
RNA serves messenger, catalytic, and regulatory roles.
What occurs during Interphase of the cell cycle?
- Growth
- DNA replication
- Protein synthesis
This phase prepares the cell for division.
List the stages of Mitosis.
- Prophase
- Metaphase
- Anaphase
- Telophase
Mitosis is the division of the nucleus.
What does the Mitosis mnemonic IPMAT stand for?
- I: Interphase
- P: Prophase
- M: Metaphase
- A: Anaphase
- T: Telophase
This helps remember the order of mitosis stages.
What is the purpose of Mitosis?
- Produce two genetically identical daughter cells
- Maintain chromosome number across generations
This ensures genetic consistency.
Define Diploid and Haploid.
- Diploid: Two sets (2n)
- Haploid: One set (n)
Humans are diploid with 46 chromosomes (23 pairs) and haploid with 23 chromosomes.
What are gametes?
Haploid sex cells (sperm, ova)
They combine at fertilization to restore diploid number.
What is the overview of Meiosis?
Reduces chromosome number by half to produce haploid gametes
Involves two successive divisions: Meiosis I and Meiosis II.
What happens during Prophase I of Meiosis?
Synapsis → homologous chromosomes form tetrads; crossing-over exchanges genetic material
This increases genetic diversity.
What occurs during Telophase II of Meiosis?
Four haploid (n) nuclei form; cytokinesis produces four gametes
This completes the meiotic process.
What is Spermatogenesis?
Male gametogenesis producing 4 sperm per diploid precursor
This process occurs in the male reproductive system.
What is Oogenesis?
Female gametogenesis producing one ovum and polar bodies
This process occurs in the female reproductive system.
