Illustration of gene inheritance and allele formation from parents.
Diagram showing genes, alleles, and the result of gene inheritance from parents, with illustrations of a child receiving genes from a father and mother.
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Show Answer Key & Explanations
Step-by-step solution for: Genes and Chromosomes: in This Lesson You Should L RN Dbe Ble To ...
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Show Answer Key & Explanations
Step-by-step solution for: Genes and Chromosomes: in This Lesson You Should L RN Dbe Ble To ...
Let's go through the worksheet "Genes and Chromosomes" step by step, solving each question and explaining the answers clearly. This appears to be a biology worksheet for an Applied Science 10 class.
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> Answer:
A gene is a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
✔ Explanation:
Genes are segments of DNA that code for specific traits (like eye color or blood type). They are passed down from parents to children during reproduction and determine various physical and biochemical characteristics.
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> Answer:
Genes are made of DNA and they are instructions to make molecules called proteins.
✔ Explanation:
DNA (deoxyribonucleic acid) contains the genetic code. Genes are sections of this DNA that provide the blueprint for building proteins. Proteins carry out most functions in cells—such as enzyme activity, structural support, and signaling—so genes indirectly control how an organism develops and functions.
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> Answer:
alleles
✔ Explanation:
Each person inherits one copy of a gene from their mother and one from their father. These two versions of the same gene are called alleles. For example, you might have one allele for blue eyes and one for brown eyes.
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> Answer:
Alleles
✔ Explanation:
This is reinforcing the definition above. Alleles are different versions of the same gene. The differences in DNA sequence between alleles can lead to variation in traits (e.g., one allele may code for curly hair, another for straight hair).
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> Answer:
phenotype
✔ Explanation:
The phenotype refers to the observable traits of an organism. It results from the interaction between the genotype (genetic makeup) and the environment. For example, if someone has a gene for tallness but doesn't get enough nutrients, they may not grow tall—so their phenotype differs from their genotype.
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> Answer:
The genetic constitution of an organism. The genotype determines the hereditary potentials and limitations of an individual from embryonic formation through adulthood.
✔ Explanation:
The genotype is the actual genetic code—an organism’s set of genes (including alleles). It defines what traits *could* be expressed. For instance, having two copies of a gene for blue eyes (BB) means your genotype for eye color is BB.
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> Answer:
phenotype
✔ Explanation:
This is a continuation of question 5. The word “phenotype” describes visible or measurable traits like height, eye color, or behavior. It's important to distinguish it from genotype, which is the underlying genetic code.
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| Term | Definition |
|------|-----------|
| Gene | A segment of DNA that codes for a specific trait |
| Chromosome | A structure made of DNA and proteins; carries many genes |
| Allele | Different versions of the same gene |
| Genotype | Genetic makeup (the combination of alleles) |
| Phenotype | Observable physical traits resulting from genotype + environment |
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- Chromosomes are found in the nucleus of eukaryotic cells (like human cells).
- Humans have 46 chromosomes (23 pairs), including 2 sex chromosomes (XX or XY).
- A karyotype is a visual representation of chromosomes arranged in pairs.
- Chromosome abnormalities (like Down syndrome due to trisomy 21) can result in developmental or health issues.
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1. Gene = Unit of heredity determining traits
2. Made of DNA; instructs protein synthesis
3. Alleles
4. Alleles
5. Phenotype
6. Genetic constitution → determines potential traits
7. Phenotype
All answers are correct and well-explained based on standard genetics principles.
Let me know if you'd like help with the PowerPoint or diagrams!
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1. WHAT IS A GENE?
> Answer:
A gene is a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
✔ Explanation:
Genes are segments of DNA that code for specific traits (like eye color or blood type). They are passed down from parents to children during reproduction and determine various physical and biochemical characteristics.
---
2. WHAT ARE GENES MADE OF AND WHAT DO THEY DO?
> Answer:
Genes are made of DNA and they are instructions to make molecules called proteins.
✔ Explanation:
DNA (deoxyribonucleic acid) contains the genetic code. Genes are sections of this DNA that provide the blueprint for building proteins. Proteins carry out most functions in cells—such as enzyme activity, structural support, and signaling—so genes indirectly control how an organism develops and functions.
---
3. EVERY PERSON HAS TWO COPIES OF EACH GENE, ONE INHERITED FROM EACH PARENT. THESE TWO, ALMOST IDENTICAL GENES ARE CALLED _________.
> Answer:
alleles
✔ Explanation:
Each person inherits one copy of a gene from their mother and one from their father. These two versions of the same gene are called alleles. For example, you might have one allele for blue eyes and one for brown eyes.
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4. _________ ARE FORMS OF THE SAME GENE WITH SMALL DIFFERENCES IN THEIR SEQUENCE OF DNA BASES BECAUSE THEY COME FROM TWO DIFFERENT PEOPLE – YOUR PARENTS.
> Answer:
Alleles
✔ Explanation:
This is reinforcing the definition above. Alleles are different versions of the same gene. The differences in DNA sequence between alleles can lead to variation in traits (e.g., one allele may code for curly hair, another for straight hair).
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5. THE PHYSICAL APPEARANCE OF AN ORGANISM, THE ORGANISM'S TRAITS SUCH AS SIZE, SHAPE, COLOUR OR BEHAVIOUR IS CALLED _____________.
> Answer:
phenotype
✔ Explanation:
The phenotype refers to the observable traits of an organism. It results from the interaction between the genotype (genetic makeup) and the environment. For example, if someone has a gene for tallness but doesn't get enough nutrients, they may not grow tall—so their phenotype differs from their genotype.
---
6. WHAT IS A GENOTYPE?
> Answer:
The genetic constitution of an organism. The genotype determines the hereditary potentials and limitations of an individual from embryonic formation through adulthood.
✔ Explanation:
The genotype is the actual genetic code—an organism’s set of genes (including alleles). It defines what traits *could* be expressed. For instance, having two copies of a gene for blue eyes (BB) means your genotype for eye color is BB.
---
7. PHENO____ TYPE DESCRIBES THE PHYSICAL CHARACTERISTICS THAT...
> Answer:
phenotype
✔ Explanation:
This is a continuation of question 5. The word “phenotype” describes visible or measurable traits like height, eye color, or behavior. It's important to distinguish it from genotype, which is the underlying genetic code.
---
✔ Summary of Key Terms:
| Term | Definition |
|------|-----------|
| Gene | A segment of DNA that codes for a specific trait |
| Chromosome | A structure made of DNA and proteins; carries many genes |
| Allele | Different versions of the same gene |
| Genotype | Genetic makeup (the combination of alleles) |
| Phenotype | Observable physical traits resulting from genotype + environment |
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📌 Additional Notes:
- Chromosomes are found in the nucleus of eukaryotic cells (like human cells).
- Humans have 46 chromosomes (23 pairs), including 2 sex chromosomes (XX or XY).
- A karyotype is a visual representation of chromosomes arranged in pairs.
- Chromosome abnormalities (like Down syndrome due to trisomy 21) can result in developmental or health issues.
---
✔ Final Answer Review:
1. Gene = Unit of heredity determining traits
2. Made of DNA; instructs protein synthesis
3. Alleles
4. Alleles
5. Phenotype
6. Genetic constitution → determines potential traits
7. Phenotype
All answers are correct and well-explained based on standard genetics principles.
Let me know if you'd like help with the PowerPoint or diagrams!
Parent Tip: Review the logic above to help your child master the concept of dna and genes worksheet answers.
