Inheritance and genetic disorders

• Science
• Upper Secondary (Key Stage 4)
• GCSE

Biology revision

Inheritance and disorders

Which shape represents females

1. Triangle
2. Square
3. Rectangle
4. Circle

Which shape represents males

1. Triangle
2. Square
3. Rectangle
4. Circle

What does a carrier look like on a family tree diagram?

1. Full shaded
2. Not shaded
3. Half shaded
4. Full shaded circle

Which of the following is a genetic disorder?

1. Cystic fibrosis
2. Malaria
3. Asthma
4. Diabetes

What causes Down syndrome?

1. Environmental toxins
2. Viral infection
3. Extra copy of chromosome 21
4. Genetic mutation

Which disorder is caused by a recessive gene?

1. Huntington's disease
2. Phenylketonuria (PKU)
3. Sickle cell anemia
4. Fragile X syndrome

What is a Punnett square used for in genetic inheritance?

1. Measuring the genetic diversity within a population
2. Predicting the possible outcomes of a genetic cross
3. Identifying recessive traits in an individual
4. Determining the dominant gene in an organism

Which of the following accurately represents a dominant allele?

1. Expressed in the phenotype when present
2. Affects only one specific trait in an organism
3. Occurs more frequently in a population
4. Always passed on to the next generation

What is the term for an individual with two different alleles for a particular gene?

1. Heterozygous
2. Polygenic
3. Phenotypic
4. Homozygous

In genetic inheritance, what is a genotype?

1. The process of genetic recombination
2. The genetic makeup of an organism
3. The physical traits of an organism
4. The expression of genes in an individual

What is the main cause of cystic fibrosis?

1. Viral mutation
2. Bacterial infection
3. Defective CFTR gene
4. Environmental factors

Which body system is primarily affected by cystic fibrosis?

1. Respiratory system
2. Digestive system
3. Nervous system
4. Circulatory system

What is the average life expectancy of someone with cystic fibrosis?

1. Around 50 years
2. Around 30 years
3. Around 40 years
4. Around 60 years

How is cystic fibrosis diagnosed?

1. Genetic testing and sweat test
2. Biopsy and lung function test
3. Urine test and MRI
4. Blood test and X-ray

What is a common symptom of cystic fibrosis in infants?

1. Excessive weight gain
2. Failure to thrive
3. Regular bowel movements
4. Normal breathing pattern

What is a recessive gene?

1. A gene that is always expressed
2. A gene that is only expressed in the absence of its dominant counterpart.
3. A gene that is unrelated to dominant genes
4. A gene that is only expressed in the presence of its dominant counterpart

How are recessive genes represented in genetic diagrams?

1. By uppercase letters
2. By lowercase letters
3. By special characters
4. By numerical symbols

What is the likelihood of expressing a recessive trait when an individual carries two recessive alleles?

1. 100%
2. 50%
3. 25%
4. 0%

What are alleles?

1. Mutated chromosomes
2. Segments of DNA
3. Genetic mutations
4. Different forms of a gene

How many alleles do individuals inherit for each gene?

1. Three alleles
2. Two alleles
3. Four alleles
4. One allele

What is the term for alleles that are the same?

1. Homozygous alleles
2. Recessive alleles
3. Heterozygous alleles
4. Dominant alleles

What term is used to describe the physical appearance resulting from the combination of alleles?

1. Genotype
2. Genetic code
3. Phenotype
4. Chromosomes