How do organisms reproduce ?

1. How do organisms reproduce? • ASEXUAL REPRODUCTION • Fission • Fragmentation • Regeneration • Vegetative Propagation • Spore Formation WHAT IS REPRODUCTION ? • SEXUAL REPRODUCTION • Reproduction in Flowering Plants • Reproduction in Human Beings

2. DEOXYRIBO NUCLEIC ACID (DNA) • Also known as “Blue Print” and “Master Copy” • Present in chromosomes in the nucleus of a cell • Contains information for inheritance of features • Information source for making proteins • First reaction takes place and DNA gets duplicated • DNAs separate from each other and make 2 different cells • DNA copies generated will be similar, but may not be identical to the original DNA DUPLICATION AND REPLICATION

3. IMPORTANCE OF VARIATION Variation is important for the survival of species as it allows some individuals to withstand and changes in the environment or niches

4. IMPORTANCE OF DNA COPYING IN REPRODUCTION DNA Copying means the production of an exact copy of the original . But the process of copying DNA will have some variation each time which leads to the stability of the population and formation of new species .

5. WHAT IS REPRODUCTION ? Reproduction is the process by which organisms generate new individuals of the same kind. Reproduction is classified into 2 types;

6. 1.ASEXUAL REPRODUCTION • It is the process of formation of new individual from any specialized or unspecialized part of a single parent without fertilization. • Asexual Reproduction is classified into 6 groups, they are; • Fission • Fragmentation • Regeneration • Budding • Vegetative Propagation • Spore formation

7. a) FISSION It is the type of asexual reproduction in which the parent cell splits into two or more daughter cells. The division can take place in any plane. BINARY FISSION IN AMOEBA MULTIPLE FISSION IN PLASMODIUM

8. b) Fragmentation • It is the type of asexual reproduction in which the parent cell is simply breaks up into smaller pieces upon maturation. Fragmentation in Spirogyra

9. c) Regeneration It is the type of asexual reproduction in which the parent cell cut or brake up into several pieces, and each piece will develop into a new individual. Regeneration in Planaria

10. d) Budding It is the type of reproduction in which a bud develops as an outgrowth due to repeated cell division at one specific site and the bud will develop to a new individual, when fully mature and detach from the parent body. Budding in Hydra

11. e) Vegetative Propagation It is the type of asexual reproduction in which the plant parts like the root, stem and leaves develop into new plants. Bryophyllum

12. VEGETATIVE PROPAGATION(CHRYSANTHEMUM)

13. VEGETATIVE PROPAGATION (PISTIA)

14. VEGETATIVEV PROPAGATION (POTATO)

15. f) Spore Formation • It is the type of asexual reproduction in which the spores in the sporangium will come out, when matured and each spore will develop into new individuals. Spore Formation in Rhizopus

16. 2.SEXUAL REPRODUCTION • It is the mode of multiplication in which young ones are formed due to the process of gamete formation.

17. FLOWER Flower is a reproductive unit of a plant Parts of a flower include sepals, petals, stamen and stigma (pistil) Pistil is the female reproductive part. Pistil consists of stigma, style and ovary Stamen is the male reproductive part Stamen consists of filament, anther and pollen

18. ADVANTAGES OF VEGETATIVE PROPAGATION The plants developed by vegetative propagation are genetically similar Plants developed by vegetative propagation bear flowers and fruits earlier than those raised from seeds Hundreds of genetically similar plants can be propagated from a single parent plant The plants which don’t produce viable seeds can be propagated only by this method It needs lass attention than those raised from seeds

19. L.S.OF A TYPICAL FLOWER

20. POLLINATION (ENTEMOPHILY)

21. POLLINATION • SELF POLLINATION Transfer of pollen grains from anther to the stigma of the same flower • CROSS POLLINATION Transfer of pollen grains from anther to the stigma of another flower of the same plant or different plant of the same species

22. PROCESS OF FERTILISATION IN PLANTS • In plants pollination is followed by fertilisation • The pollen grains deposited on the stigma germinated to form a pollen tube • Simultaneously the nucleus present in the pollen grain divides in to two male gametes • The pollen g[tube bearing two male gametes penetrate through the style reaches the ovary and enter in to the embryo sac through the micropyle

23. DOUBLE FERTILIZATION

24. POST FERTILISATION CHANGES • One of the male gamete fuses with the egg (ovum) to form a diploid zygote .this process of fertilization is called zyngamy • Another male gamete fuses with two polar nuclei to form a triploid PEN (primary endosperm nucleus) .This ferilisation is called triple fusion • As two fertilisation takes place simultaneously in the embryo sac ,this process is called double fertilisation. • After fertilisation ,the zygote changes in to embryo and the PEN changes in to endosperm • The endosperm provides nutrition to the developing embryo • After fertilisation , the sepals and petals fall off and the ovary changes in to fruit and the ovules changes in to seeds

25. MALE REPRODUCTIVE SYSTEM • Male reproductive system consists of a pair of testes .the testes lie in a muscular bag called scrotum which lie outside the abdominal cavity .There is tubular structure arise from each testis and is called vas deferens. It unites with a duct arising from the urinary bladder and form a common tube called urethra. The urethra is enclosed within a muscular organ called penis • Scrotum lie outside the abdominal cavity between two legs because the production of sperm requires a lower temperature (2—2.5 C less ) than the normal body temperature • Functions of testes 1. production of sperms 2. secretion of male hormone testosterone

26. Male Reproductive System

27. FEMALE REPRODUCTIVE SYSTEM Female reproductive system consists of a pair of ovaries which are located in the abdominal cavity near kidneys each ovary contains a large number of follicles which on maturation at puberty becomes eggs Near the posterior end of each kidney there is a funnel shaped structure called fallopian tube or oviduct . The fallopian tube opens in to the uterus .the uterus opens in to vagina through cervix Functions of ovary 1. production of egg or ovum 2. secretion of female hormone estrogen

28. Female Reproductive System

29. ACCESSORY GLANDS ASSOCIATED WITH THE MALE REPRODUCTINE SYSTEM .Seminal vesicle secretes an alkaline viscous liquid semen which provides nutrients to the sperm .Prostrate gland secretes a milky fluid which makes the sperms to transport faster Cowper’s gland secrets a fluid which acts as a lubricant

30. ROLE OF PLACENTA Placenta is special disc shaped tissue found on the inner wall of the uterus . The embryo gets nutrients and oxygen from the mothers blood with the help of placenta through umbilical cord it also transport waste materials and carbon dioxide from the foetus to the mothers blood

31. WHAT HAPPENS IF FERTILISATION DOES NOT OCCUR The inner lining of the uterine wall slowly breaks and comes out through the vagina as blood and mucous known as menstruation It occurs every month and lasts for 2 to 5 days

32. DIFFERENT METHODS OF CONTRACEPTION 1.Natural method 2.Barrier method 3.Chemical method 4.Surgical method Natural methods –abstinence and withdrawal Abstain from coitus from day 10 to 17 of the menstrual cycle Withdrawal of the penis from vagina before ejaculation Barrier method – in this method , physical devices such as condom , diaphragms, cervical ca[ps etc are used which prevents the entry of sperm in to the female genital tract during mating IUCD s such as loop and copper T are safely placed safely inside the uterus which prevent fertilization and implantation . the copper ions suppresses the mobility and fertilizing capacity of the sperms

33. Chemical methods –use of oral or vaginal pills or chemicals that change the hormonal balance of the body so they prevent the ovulation and fertilization – surgical methods – in this method a small portion of the vas deferens in males and fallopian tubes in females are surgically legated or tied .it is called vasectomy in males and tubectomy in females ‘It is an ideal method of contraception

34. EXPAND 1.HIV—Human Immunodeficiency Virus 2.AIDS---Acquired Immuno Deficiency Syndrome 3.IUCD---Intra Uterine Contraceptive Device 4.OC---Oral Contraceptive 5.STD---Sexually Transmitted Diseases 6.STI---Sexually Transmitted Infections 7.RTI---Reproductive Tract Infections 8.ARSH---Adolescence Reproductive and Sexual Health

35. PRESENTED BY, P.V MANOHARAN K.V NO 1 CPCRI KASARAGOD