Inherited medical conditions and codominance

Inherited medical conditions and codominance

Presentation of jamboards

Teacher-led discussion

Group work

Quiz

Presentation of Jamboards

Groups 1-4

Multiple Choice

People with albinism do not produce this pigment.

• melanin

• chlorophyll

• albinin

• melanyll

Multiple Select

What are the characteristics of people with albinism? Tick all that apply.

• pale skin

• light hair

• pink eyes

• sensitive to bright light

• high tolerance to sunlight

Multiple Select

What are the characteristics of people with albinism? Tick all that apply.

• pale skin

• light hair

• pink eyes

• sensitive to bright light

• high tolerance to sunlight

Multiple Choice

Which is an example of codominance?

• human blood type

• malaria

• sickle cell anemia

• albinism

Albinism

People with albinism do not produce melanin.

Characteristics

• Pale skin, pink eyes, light hair

• sensitive to bright light and burn easily under sunlight

Albinism is caused by a recessive allele

Multiple Choice

What causes albinos' pink eyes?

• blood in retina showing up

• special pigment in retina showing up

• sensitivity to light causes retina to turn pink

Multiple Choice

A parent is a carrier of albinism. Which statement is INCORRECT?

• parent is heterozygous

• parent has normal skin

• parent is also albino

Multiple Select

Both parents are carriers of albinism. Which is CORRECT about their offspring? Tick two.

• 25% are carriers

• 25% are albinos

• 50% are carriers

• 50% are albinos

Sickle Cell Anemia

A disease in which red blood cells can't carry enough oxygen.

Punnet square between heterozygous carriers of the sickle cell anemia

However, there is a benefit.

• heterozygotes have both the sickle cell allele and the normal allele

• they produce enough normal blood cells to reduce the effects of sickle cell anaemia, but also produce enough sickle cells to have increased resistance to malaria

In areas where malaria is common, there is a higher incidence of people who carry the HbS allele.

Multiple Choice

Which is the symbol for the sickle cell allele?

• Hb^A

• Hb^S

Multiple Choice

A person is a carrier of the sickle cell allele. What is the genotype of this person?

• Hb^A Hb^S

• Hb^A Hb^A

• Hb^S Hb^S

Multiple Choice

What is the benefit of having the Hb^AHb^S genotype?

• increased resistance to malaria

• increased resistance to sickle cell anemia

• die easily from malaria

• die easily from sickle cell anemia

Multiple Select

If both parents carry the sickle cell allele, what is the probability of their offspring having the sickle cell disease?

• 0%

• 25%

• 50%

• 75%

Codominance in human blood groups

In humans, there are three alleles for blood groups: I^A, I^B, I^O

Codominance, in genetics, is a phenomenon in which two alleles are both expressed within an organism.

In human blood groups, the I^A and I^B alleles are neither dominant to each other, although both are dominant to the I^O allele.

Cross between parents whose blood types are AB and O.

• 50% of the offspring are blood type A

• 50% of the offspring are blood type B

Multiple Select

What are the three alleles for human blood groups? Tick three.

• I^A

• I^B

• I^O

• I^C

Multiple Select

What are the possible genotypes of a person whose blood type is A? Tick all that apply.

• I^AI^B

• I^AI^O

• I^AI^A

• I^BI^B

• I^BI^O

Multiple Choice

How many genotypes are possible for a person who has the blood group O phenotype?

• one

• two

• three

• four

Poll

I learned and will remember many things from this lesson.

• strongly agree

• agree

• disagree

• strongly disagree

Summary

• Albinism and sickle cell anemia are inherited medical conditions and are both caused by a recessive allele.

• The sickle cell allele offers an increased resistance to malaria.

• Codominance occurs when both alleles are expressed in an organism.

• The human blood type is an example of codominance.