Explanation

• Species is the basic unit of classification.
• Species are a group of organisms that are morphologically similar and can interbreed.
• Classification system as proposed by Linnaeus.

These groups or levels are:

1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus 
7. Species

Species is the smallest unit of classification.

Last verified on 20-05-2026

Explanation

• Homologous organs are studied in evolution.
• They help explain common ancestry of organisms.
• These organs may look different in function.
• But they share similar internal structure and origin.
• They are evidence of divergent evolution.

Last verified on 20-05-2026

Explanation

• DNA replication is the process of copying DNA.
• It ensures genetic information is passed to new cells.
• Several enzymes work together in this process.
• DNA polymerase is a key enzyme in replication.
• It helps build the new DNA strand accurately.

Last verified on 20-05-2026

Explanation

• Transcription is the process of making RNA from DNA.
• It is the first step of gene expression.
• In eukaryotic cells, DNA is present inside the nucleus.
• RNA is synthesized using DNA as a template.
• This process is essential for protein formation.

Last verified on 20-05-2026

Explanation

• Stabilizing selection is a type of natural selection.
• It favors average (intermediate) traits in a population.
• Extreme traits are selected against.
• It reduces variation in a population.
• It keeps the population stable around the mean value.

Last verified on 20-05-2026

Explanation

• Natural selection is a process of evolution.
• It favors traits that help organisms survive and reproduce.
• Beneficial traits become more common over generations.
• Harmful traits tend to decrease in frequency.
• It depends on environmental conditions.

Last verified on 20-05-2026

Explanation

• A population bottleneck occurs when a large population suddenly becomes very small.
• This is usually due to disasters, diseases, or environmental changes.
• Only a few individuals survive and reproduce.
• Genetic drift becomes very strong in small populations.
• It reduces genetic diversity in the population.

Last verified on 20-05-2026

Explanation

Explanation

• Meiosis is a special type of cell division in living organisms.
• It occurs in reproductive cells (germ cells).
• It reduces chromosome number from diploid (2n) to haploid (n).
• It produces genetically different cells.
• Final result is formation of gametes.

Last verified on 20-05-2026

Explanation

• A cross between two heterozygous individuals (Aa × Aa) is a monohybrid cross.
• Each parent produces two types of gametes: A and a.
• Offspring combinations are AA, Aa, Aa, and aa.
• This gives a characteristic Mendelian ratio in genotype.
• It follows simple inheritance laws proposed by Mendel.

Last verified on 20-05-2026