Respiration and Circulation — BIOLOGY STD 12 Science — Question

The diagram shows a part of the human female reproductive system.

1. Name the gamete cells that would be present in 'X', if taken from a newborn baby.
2. Name 'Y' and write its function.
3. Name 'Z' and write the events that take placehere.

Haemophilia is a sex linked recessive disorder of humans. The pedigree chart given below shows the inheritance of haemophilia in one family. Study the pattern of inheritance and answer the questions given.

1. Give all the possible genotype of the members 4, 5 and 6 in the pedigree chart.
2. A blood test shows that the individual 14 is a carrier of haemophilia. The member numbered 15 has recently married the member numbered 14. What is the probability that their first child will be a haemophilic male?

How HIV multiplies in the host body?

1. List the two methodologies which were involved in human genome project. Mention how they were used.
2. Expand ‘YAC’ and mention what was it used for.

Explain any three advantages the seeds offer to angiosperms.

Answer the following questions:
Explain sex determination in humans.

The outline structure of a drug is given below,

1. Which group of drugs does this represent?
2. What are the modes of consumption of these drugs?
3. Name the organ of the body which is affected by consumption of these drugs.

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What are the functions of three types of RNAs in bacteria? Which enzyme is involved in transcription of DNA to form RNAs in bacteria? What is its function?

Describe the structure of sex chromosomes with the help of labelled diagram.

1. What do ‘Y and ‘B’ stand for in ‘YAC’ and ‘BAC’ used in Human Genome Project (HGP)? Mention their role in the project.
2. Write the percentage of the total human genome that codes for proteins and the percentage of discovered genes whose functions are known as observed during HGP.
3. Expand ‘SNPs’ identified by scientists in HGP.