Download Revision for biology test 2 File

Yr 10 Science Biology
Exam Revision
Name
Q1. Write down the definitions of the following terms:
Homozygous:
Heterozygous:
Dominant gene:
Recessive gene:
Phenotype:
Genotype:
Q2. A black cat mated with a red cat. All of the offsprings were born black.
a) determine the dominant characteristic (colour).
b) work out the genotypes of the offsprings(hint: use punnet square).
c) state the phenotype of the offsprings.
Q3. a red guinea pig is crossed with a white guinea pig. The offsprings were all
cream.
a) state the type of inheritance in this instance.
b) what are the genotype/s of the offsprings?
c) if one offspring mated with a white guinea, what is the chance of having a red
pig?
Q4. A pure normal individual carrying the gene A mates with an albino. Given
that albinism is a recessive condition, and carries the gene a, answer the following:
a) determine the genotype of the albino individual.
b) determine the genotype of the normal individual.
c) determine the genotype of the offsprings.
d) if two offsprings are crossed, determine:
i) the percentage of having an albino child.
ii) the percentage of having a normal child.
iii) the percentage of having a hybrid child.
e) if a heterozygous mates with an albino, what is the chance of having:
i) an albino child?
ii) a normal child?
iii) a hybrid child?
iv) a pure normal child?
f) if a heterozygous mates with a pure normal person, what is the chance of
having:
i) an albino child?
ii) a normal child?
iii) a hybrid child?
iv) a pure normal child?
Q5. A black bull mates with a white cow. A gray calf is born.
(a) What type of inheritance is this?
(b) When two members of the first generation are crossed, determine:
(i)
The probability of producing a brown calf.
(ii)
The probability of having a gray calf.
(iii) The genotypic ratio of their offspring.
Q6. A red rose is crossed with a white rose to produce all pink roses in the first
generation. If 2 pink roses are crossed together, determine:
(i) the phenotypic ratio of the second generation.
(ii) the genotypic ratio of the second generation.
Q7. A male with free (F) earlobes mates with a female with attached (f)earlobes.
All the offsprings are born with free earlobes.
(i) what type of inheritance is this?
(ii) Draw a punnet square to show possible genotypes.
(iii) what percentage of the offsprings are pure bred?
Q8. A hybrid black mouse is crossed with a pure white mouse. Determine:
(i)
which colour is dominant?
(ii)
the genotype of the dominant mouse.
(iii) the genotypic ratio of offsprings.
Q9. Two hybrid flowers are crossed together. Determine:
(i)
the percentage of offsprings showing the dominant feature.
(ii)
the percentage of offsprings showing the recessive feature.
Q10. List the bases that make up the ‘rungs’ on DNA. Indicate which bases go
together.
Q11. An albino male is crossed with a normal-coloured female. Albinism is a
recessive condition. A stands for normal pigmentation, and a stands for albinism.
1
3
4
2
5
6
8
(i)
7
9
10
write the genotype of individuals 1, 2 and 4.
(ii) what is the probability the individuals 1 and2 will have albino offsprings?
(iii) a homozygous normal individual 7 is mated with individual 6. List possible
genotypes of their offsprings.
(iv) determine the % of the offsprings from couple 6 and 7 who carry the a gene.
Q12. An extended family has mapped their ability to roll their tongue using a
pedigree.
(i)
Write down what type of inheritance does the pedigree show.
(ii)
if T stands for tongue-rollers and t stands for non-rollers, write down
the genotypes of all individuals in the pedigree.
1
3
4
2
5
6
Q13. What determines the gender of an individual?
Q14. List four sources of variation.
Q15. A man is carrying a mutated gene on his X chromosome. Are his children
likely to inherit the condition? Explain.
Q16. A bird dangles a piece of bread, left by humans, in the water to catch fish.
What type of adaptation is this?
Q17. A salmon can regulate how much salt it can remove from its tissue. What
type of adaptation is this?
Q18. Study this pedigree. Is this an X-linked or autosomal type of inheritance?
Justify your answer.
1
3
4
2
5
6
8
7
9
Q19. A non-venomous king snake has evolved over the years to resemble the
poisonous coral snake. In its current form it is surviving in its new environment.
Explain the reason behind its survival.
Q20. Gregor Mendel wanted to grow dwarf citrus plants as ornaments in as little
time as possible. He has four plants with the following genotypes: TT, Tt and tt.
Assuming T stands for tallness and t for dwarfism, determine which combination
of genotypes he would have to cross together to yield the greatest number of dwarf
plants, given he cannot use two homozygous dwarf plants.