GENE, DNA, AND CHROMOSOMES RELATIONSHIP
An Overview of Gene, DNA and Chromosomes Relationship
Prepared BY: Maria Johanna Baguio Testa
GENE, DNA, AND CHROMOSOMES RELATIONSHIP
DNA is a long molecule made up of nucleotides.
Genes are segments of DNA that code for specific proteins.
Chromosomes are tightly coiled structures of DNA found in the nucleus.
Humans have 23 pairs of chromosomes, containing thousands of genes.
GENETIC INHERITANCE: DOMINANT VS RECESSIVE
Traits are determined by pairs of alleles.
A dominant allele masks the expression of a recessive one.
Example: B (brown eyes) is dominant over b (blue eyes).
GENOTYPE, PHENOTYPE, AND RATIOS
Genotype: Genetic makeup (BB, Bb, bb)
Phenotype: Observable trait (Brown or Blue eyes)
Cross: Bb x Bb
Genotype ratio: 1 BB : 2 Bb : 1 bb
Phenotype ratio: 3 Brown : 1 Blue
MITOSIS VS MEIOSIS
Mitosis: One division → 2 identical cells (growth, repair)
Meiosis: Two divisions → 4 different cells (reproduction)
Mitosis conserves chromosome number; meiosis halves it.
GENETIC DISEASES: GENE/CHROMOSOME CHANGES
Mutations in genes or abnormalities in chromosomes can cause diseases.
Examples:
- Cystic fibrosis (gene mutation)
- Down syndrome (extra chromosome 21)
BENEFITS OF UNDERSTANDING GENETIC DISEASES
- Early diagnosis and treatment
- Family planning support
- Better public awareness
- Helps reduce stigma and improve health outcomes
PRE-MARITAL GENETIC COUNSELING
- Assess risk of inherited conditions
- Identify carriers of genetic disorders
- Plan for safe and healthy pregnancies
- Important for couples with family history of genetic diseases
GMOS: USES AND EFFECTS
- Used to enhance crop yield, pest resistance, and nutrition
- Human impact: Allergen concerns, ethical debates
- Environmental impact: Potential biodiversity loss, resistant pests
- Data Source: WHO, Khan Academy
IMPACTS AND BENEFITS OF GMOS
Benefits:
- Improved food supply
- Reduced chemical use
Impacts:
- Ethical and environmental risks
Dissemination of reliable information is key to public understanding
BIODIVERSITY VS SPECIES DIVERSITY
- Biodiversity: Variety of life in an ecosystem
- Species diversity: Number of different species in an ecosystem
- Greater diversity → More resilience to changes
BIODIVERSITY'S ROLE IN ECOSYSTEMS AND HEALTH
- Maintains ecosystem balance
- Provides food, medicine, and raw materials
- Protects against diseases and natural disasters
- Supports climate regulation
CONCLUSION
- Understanding genetics and biodiversity helps in health, agriculture, and environmental protection.
- Informed decisions lead to better quality of life for future generations.
END