CBSE ADDA

One mark question Q1. Name the type of fission carried out by amoeba.        Ans.  Binary fission. Q2.  What is vegetative propagation? Ans. When new plants are grown by using vegetative parts like root, stem and leaves it is known as vegetative propagation. Q3. Name an organism which reproduces by multiple fission. Ans. Plasmodium {malarial parasite} Q4. What is Puberty? Ans. The age at which the human males and females becomes sexually mature is called puberty. Q5. What is pollination? Ans. The transfer of pollen grains from anther to the stigma of the same or another flower of the same kind is called pollination. Q6. What is fertilization? Ans. The fusion of male and female gametes is called fertilization. Q7. What is placenta? Ans. The tissue connecting developing embryo {foetus} and mother is called placenta. Q8. What is asexual reproduction? Ans. The process of reproduction in which only one parent is involved and no sex

Q1)Define evolution. Ans-It a slow gradual process which occurs due to cumulative effects of adaptations and helps it to survive in a better way. Q2)How are fossils helpful in developing evolutionary relationships? Ans: Fossils forms a connecting link between groups of organisms. Q3)Cat’s paw ,human hand and horse’s legs-are these organs homologous or analogous? Give reason Ans- They are homologous organs as they are of same origin performing different functions.origin is forearm modified. Q4)Wings of bird and wings of insect-are these organs homologous or analogous?give one suitable season to support your answer. Ans-They are analogous organs as both have developed from different origin and perform same function of flying. Q5)Give one difference between eyes and eye spot.Which animal possesses eye spots? Ans-eyes are well developed organs helping to form an image, but eye spots just enable the animal to distinguish between day light and darkness.e.g. pl

  Chapter 9 Heredity and Evolution solved Questions for slow lerner        Very short answer type Question 1) Name the scientist who proposed the theory of natural selection. Ans- Charles Darwin. 2) What is micro-evolution? Ans-Evolution on a relatively small scale 3) Write the expended form of DNA. Ans-Doxyribo Nucleic Acid 4) Name two human traits which show variation. Ans- Colour of eyes and height of an individual. 5) What type of reproduction give rise to more number of successful variation? Ans- Sexual reproduction. 6) What is the basis of evolution? Ans-Selection of variants by environmental factors forms the basis of evolution. 7) Older fossils are found closer to the surface-True or False. Ans- False. 8) What will be the sex of a child who inherit Y Chromosome from his/her father? Ans- The sex of the child will be boy. 9) If a trait A exists in 10% of population of an asexually reproducing species and a trait B exists in 60%  of the sa