Which of the following statements is true of yeast?

Which of the following statements is true of Bryophyllum?

Chiropterophily means...

Through which cell of the embryo sac, does the pollen tube enter the embryo sac?

Which one of the following pairs of plant structures has a haploid number of chromosomes?

1st polar body is formed at which state of oogenesis?

Which one of the following is the most likely root cause why menstruation is not taking place in the regularly cycling human female?

Sertoli cells are found in

Which of the following represents a condition where the motility of the of the sperms is highly reduced?

Spermatids are transformed into spermatozoa by

Which one of the following events is correctly matched with the time period in a normal menstrual cycle?

Which accessory genital gland occurs only in mammalian male?

Positive feedback loop signals from fully developed fetus and placenta ultimately lead to parturition which requires the release of 

Which of the following birth control measures can be considered as the safest?

How does sexual reproduction enable organisms like algae and fungi to survive during unfavourable conditions?

What are
(a) continuous breeders and
(b) seasonal breeders?

How do homogameters differ from heteroga-metes?

In general, the male gametes are motile while the female gametes are stationary.  Mention two types of exceptions to this, with an example for each.

Is Marchantia monoecious or dioecious? Why? where are the sex organs borne in this plant?

What are hermaphrodites? Name two hermaphrodite animals

How many are the cells of tapetum different from the cells of the other wall layers?

What is filiform apparatus? What is its function?

What is mwant by LH-surge?When does it occur?

Give reasons why family planning techniques are not adopted by all in our country.

(a) Explain triple fusion in angiosperms.
(b) Write the fate of the product of this fusion in the mature fruit of coconut.

(a) In plant breeding experiments, pistillate flowers are not emasculated, but are still bagged. Explain.
(b) Why are outbreeding devices developed by some flowering plants?

Each pollen grain produces two male gametes.How many pollen grains will be required to fertilise 4 ovules present in a particular carpel?Give reasons in support of your answer.

Name the following structures:
(a) Single cotyledon of the monocotyledonous embryo of grass family.
(b) The portion of embryonal axis above the level of cotyledons in dicotyledonous embryo.
(c) Occurrence of more than ore embryo in a seed
(d) Seedless fruits produced without fertilization.

Mention the target cells of lutenising hormone in human males and females.Explain the effect and the changes which the hormone induces in each case.

Describe the structure of seminiferous tubule.

Give a schematic view of spermatogenesis in human.

You must have seen your mother adding 3-4 globules of yeast to the idli paste she has prepared.  Similarly, brewing industry uses yeast in the manufacture of alcohol.
(a) How does such a small amount of yeast added help to produce thousands of litres of alcohol? Explain how yeast multiples so fast.
(b) Name the process carried out by yeast in these cases.
(c) What value is learnt from these?

A farmer cultivates sugar cane and rose by usin stem cuttings.  He found that some of the cuttings did not continue to grow into new plants.  As a student of Agriculture; Shanu gives some points to be followed.
(a) Can you suggest a reason for this?
(b) Enlist the aspects that Shanu must have given for consideration, while preparing stem cuttings for propagation.
(c) Name two other plants which are also propagated by stem cuttings.
(d) What value (s) is/are shown by Shanu?

Jagan has two mango trees in the backyard  of his house, which yielded fruits for the first time during this summer.  The fruits were small, fibrous and not so sweet.  In the next house, where his friend Ajay livers, there is a mango tree, which yields fruits that are fleshy/juicy, very sweet and bigger in size.  Ajay, a student of B.sc. (Botany) comes out with an idea and takes some branches from the jagan's garden to his garden and explains the procedure.
(a) What method do you think Ajay has suggested for getting good quality fruits, on the trees of Jagan's house in a short period of time, i.e. during the next season?
(b) Describe how it is carried out to help japan.
(c) What are its advantages over growing a mango tree with the seeds obtained from Ajay's garden?
(d) Mention the values expressed by Ajay in this case.

Explain the development of the zygote into an embryo and of the primary endosperm nucleus into an endosperm in a fertilised embryo sac of a dicot plant. 

(a) Draw a labelled longisectional view of an albuminous seed.
(b) How are seeds advantages to flowering plants?

Describe the Similarities between Spermatogenesis and Oogenesis.

How can education help in building up a socially responsible and reproductively healthy society?
(Enumerate the aspects that should be emphasised).

Write a notes population growth rate.

During a visit to Vaishno Devi, Rahul came across a young couple staying in the adjacent room in the hotel.
He learned that the couple had been visiting different temples and performing rituals to get a child. Rahul was astonished and explained to them about ART which he had recently studied in biology. The couple were happy and understood their wrong approach and thanked Rahul.
(i) What is ART? What is the various method included in ART?
(ii) What are the limitations for which ART is not commonly accepted?
(iii) Identify the values which Rahul showed.