Heredity and Evolution

Only variation that confer and advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

Study the given data and answer the questions following the data:

Parental plants cross fertilised and seeds collected F1 First Generation offsprings F2 Offsprings of self

pollination of F1 Male parents always bare red flowers. Female parent always had white flowers.

330 seeds sown and observed. All 330 gave red flowers. Out of 44 seeds 33 seeds gave plants with red

flowers and 11 seeds gave plants with white flowers.

i. What is the term for this type of cross?

ii. What does the data of the column marked F1 indicate?

iii. Express the gene type of the (a) parents (b) F1 progeny and (c) F2 progeny

How do we know how old a fossil is?

What are the causes of variations in clones?

The human hand, cat paw and horse foot when studied in detail show the same structure of bones and point towards a common origin.

i. What do you conclude from this?

ii. What is the term given to such structures?

The gene type of green stemmed tomato plants is denoted as GG and that of purple stemmed tomato plants as GG when these two are crossed.

i. What colour of stem would you expect in F1 progeny?

ii. Give the percentage of purple stemmed plants if F1 are self pollinated.

iii. In what ratio would you find the gene types CG and Gg in the F2progeny?

The gene type of green stemmed tomato plants is denoted as GG and that of purple stemmed tomato plants as GG when these two are crossed.

When Mendel crossed a Tall plant with a dwarf plant, no medium height plants were obtained in F1 generation. Why?

What are inherited traits? Give one example.

Name 2 organisms in which sex determination is regulated by environmental factors.

What is the percentage possibility a couple of having daughters?

Why males are called heterogametic?

Name the chemicals which were essential for origin of life.

Why are traits acquired during life-time of an individual not inherited?

What is an offspring?

. In evolutionary terms, which among-bacteria, spider, fish and chimpanzee have a “better” body design? Why or why not?

Mendel crossed a pure white recessive pea plant with a dominant pure red flowered plant. What will be the first generation of hybrids?

What will be the percentage of ab gametes produced by AaBb parent?

Is it true that when a new species is emerged, the old species is eliminated and why?

What is called phylogenetic system of classification?

Why are the small number of surviving tigers a cause of worry from the point of view of genetics?

Write the characteristics on the basis of which duck-biled platypus is considered as a link between reptiles and mammals.

Mention any two recessive traits of garden pea.

A normal pea plant bearing colored flowers suddenly start producing white flowers. What could be the possible cause?

If the sperm bearing Y-chromosome fertilizes the egg, the child born will not be entirely like his father. Why is it so?

Why are asexually reproducing organisms capable of showing hereditaryfeatures?

Who provided experimental evidence to support theory of origin of life from inanimate matter?

What happened when Mendel crossed two traits of a character in a pea plants?

How one is change adopted to perform different functions? Give one example

Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

How is the equal genetic contribution of male and female parents ensured in the progeny?

Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

What evidence do we have for the origin of life from inanimate matter?

Explain the importance of fossils in deciding evolutionary relationships.

Outline a project which aims to find the dominant coat colour in dogs.

Explain the terms analogous and homologous organs with examples

 How are the areas of study- evolution and classification - interlinked?

A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?

In evolutionary terms, we have more in common with

(a) a Chinese school-boy.

(b) a chimpanzee.

(c) a spider.

(d) a bacterium.

An example of homologous organs is

(a) our arm and a dog's fore-leg.

(b) our teeth and an elephant's tusks.

(c) potato and runners of grass.

(d) all of the above.

A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as

(a) TTWW

(b) TTww

(c) TtWW

(d) TtWw

In evolutionary terms, can we say which among bacteria, spiders, fish and chimpanzees have a 'better' body design? Why or why not?

Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species?

What are fossils? What do they tell us about the process of evolution?

Can the wing of a butterfly and the wing of a bat be considered homologous organs? Why or why not?

Give an example of characteristics being used to determine how close two species are in evolutionary terms.

Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually? Why or why not?

Will geographical isolation be a major factor in the speciation of a self-pollinating plant species? Why or why not?

What factors could lead to the rise of a new species?

Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics?

Why are traits acquired during the life-time of an individual not inherited?

What are the different ways in which individuals with a particular trait may increase in a population?

How is the sex of the child determined in human beings?

A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits - blood group A or O - is dominant? Why or why not?

How do Mendel's experiments show that traits are inherited

How do Mendel's experiments show that traits may be dominant or recessive?

How does the creation of variations in a species promote survival?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?