Human Reproduction PDF

REPRODUCTION AND DEVELOPMENT OF PLANTS AND ANIMALS WHAT IS REPRODUCTION ? - Is the process by which animals produce offspring for the purpose of continuing the species. - Is the process by which living things produce young ones of their own kind. - Is the biological proce...

REPRODUCTION AND DEVELOPMENT OF PLANTS AND ANIMALS WHAT IS REPRODUCTION ? - Is the process by which animals produce offspring for the purpose of continuing the species. - Is the process by which living things produce young ones of their own kind. - Is the biological process by which new individual organisms are produced. Reproduction is a biological process in which different organisms have the ability to produce another of their kind. With this ability, organisms are able to improve them species and enhance their physical characteristics, because only those that have the genes necessary for survival can proliferate and pass them on to the next generation. TYPES OF REPRODUCTION 1.ASEXUAL 2.SEXUAL What is ASEXUAL REPRODUCTION? - The production of new organism from a single parent without the involvement of sex cells (gametes) - The offspring produced are exact copies of their parents. What is SEXUAL REPRODUCTION? - The production of a new organism from two parents by making use of their sex cells. - The reproduction in which both male and female reproductive organs involved to give birth to new individual. What is Development? - the progressive changes in size, shape, and function during the life of an organism by which its genetic potentials (genotype) are translated into functioning mature systems (phenotype). - Refers to physiological and functional maturation of an organism. - Development is the process by which a multicellular organism, beginning with a single cell, goes through a series of changes, taking on the successive forms that characterize its life cycle. MALE REPRODUCTIVE SYSTEM TESTIS- produce sperm cells SCROTUM- pouch like sac that holds the testis PENIS- places sperms into vagina during mating  VAS DEFERENS- transports mature sperm to the urethra, the tube that carries urine or sperm to outside of the body, in preparation for ejaculation  GLANDS- provide liquid in which sperm can swim a. SEMINAL VESICLE- secretes one of the components of the semen b. Prostate gland- secretes a milky fluid that is discharged into the urethra as part of the semen. c. BULBOURETHRAL GLAND - Mucuos secreting glands located at the base of the penis. FEMALE REPRODUCTIVE SYSTEM FUNCTIONS: 1. Production of female sex cells 2. Reception of sperm cells from the male 3. Nurturing the development of, and providing nourishment for, the new individual Parts: ovary- produce egg cells Oviduct- passageway of eggs from the ovary to the uterus ( also the same place where the egg is fertilized) Uterus- place where fertilized egg develops Vagina- receives penis of male during mating HUMAN GROWTH AND DEVELOPMENT FERTILIZATION- begins with the fusion of sperm and egg cell to form a fertilized egg called a zygote. The journey will take about 6-7 days of fertilization. The zygote is like a ball of cells attached itself to the uterine lining ( endometrium) of the uterus in the process called implantation. When the zygote is already attached, it is known as embryo The embryo or fetus will stay in the uterus for 9 months to develop until it is ready for birth. WHAT IS FERTILIZATION? - Is the fusion of haploid gametes, egg and sperm to form the diploid zygote - Process which occurs naturally within the body or through reproductive technologies outside the body. 2 TYPES OF FERTILIZATION 1. INTERNAL 2. EXTERNAL What is internal fertilization? - Takes place the inside the female body - Internal fertilization refers to the combination of an egg and a sperm cell in sexual reproduction within the female body - Lesser gametes are discharged and placed into the female’s body. - Male gametes are the only ones that are released into the female vaginal canal. - Inside the female body, additional development occurs. What is External Fertilization? - External fertilization is a type of reproduction in which the sperm of a male creature fertilizes the egg of a female organism outside the female’s body. - External fertilization is a type of fertilization in which the union of a male gamete and a female gamete occurs externally in the body. Although animals that undergo external fertilization, such as frogs and fish, deposit hundreds of eggs, not all of them are fertilized and so do not mature into young frogs. - External fertilization is used by many fish, amphibian species, and other reproductive aquatic organisms. External fertilization is advantageous since the mother is relieved of the physical burden of carrying the developing kid. SEXUAL REPRODUCTION IN PLANTS: Flowering plants, reproduce sexually through a process called POLLINATION. Flowers contain male sex organs called stamens and female sex organs called pistils. The anther is the part of the stamen that contains pollen. Pollen must be moved to a part of the pistil called the stigma for reproduction to take place. What is POLLINATION ? - Is the act of transferring pollen grains from the male anther of a flower to the female stigma. - Pollen grains are transferred mainly by water, wind, insects and animals. Why do plants need to be pollinated? - The plant uses the pollen to produce a fruit or a seed.  The outermost parts of the flower are green structures called SEPALS; They protect the flower before it opens. Inside the sepals are the PETALS; they are usually colorful.  MALE ORGAN OF A FLOWER: a. STAMEN- male reproductive part of a flower b. ANTHER- makes tiny grains called “pollen” which contains male sex cells. c. FILAMENT- holds up the anther FEMALE ORGANS OF A FLOWER: a. CARPEL – female reproductive part; innermost part of the flower b. STIGMA- top part of the carpel with sticky surface to trap the pollen c. STYLE- joins the stigma and the ovary d. OVARY- contains the female sex cells called ovules; there is where the eggs are located SELF POLLINATION happens when a plant’s own pollen fertilizes its own ovules. - Self pollination is the transfer of pollen grains from the anther to the stigma of the same flower. - Is considered sexual reproduction because in this process gametes produced from different sex cells fertilize to produce a complete plant. CROSS POLLINATION- happens when the wind or animals move pollen from one plant to another. - And when pollen grains from a flower of one plant are carried to the stigma of a flower of another similar plant. POLLINATORS are animals that carry pollen between plants. - Insects like bees, butterflies, moths and beetles. - Some birds; like mammals – bats and rodents. - The colors and smells of flowers often attract pollinators. SEXUAL REPRODUCTION IN ANIMALS The process in which the male and female gametes fuse together to form a new individual is called sexual reproduction. The male reproductive organs comprise a pair of testes, sperm ducts, and a penis. The sperms are produced by the testes. The sperms are very small in size with a head, a middle piece, and a tail The female reproductive organs comprise a pair of ovaries, oviducts, and the uterus. The eggs (ova) are produced by the ovaries. The development of the baby takes place in the uterus. A mature egg is released into the oviduct every month Process of Sexual Reproduction in Animals Fertilization The semen contains millions of sperm. A single sperm fuses with the ova during fertilization. The nuclei of the egg and the sperm fuse together to form a single nucleus. Thus, a zygote is formed Fertilization is of two types: Internal Fertilization The fertilization that takes place inside the body of the female is known as internal fertilization. For eg., humans, cows, dogs, etc. This method is more prevalent in terrestrial animals. However, some aquatic animals also adopt this method. This may take place by direct introduction of sperms by the male in the female reproductive tract, or the male deposits the sperms in the environment which is picked up by the female in her reproductive tract There are three ways by which offspring are produced by internal fertilization 1. Oviparity– The fertilized eggs are laid outside, where they receive nourishment from the yolk 2. Ovoviviparity– The fertilized eggs are retained in the female’s body where they receive nourishment from the yolk. The eggs are laid right before they are hatched 3. Viviparity– The offspring are born directly instead of hatching from the eggs. They receive nutrition from the mother. This can be seen in mammals External Fertilization The fertilization that takes place outside the female is called external fertilization. For eg., frogs, and fish. Most fertilization takes place during the process of spawning. Environmental signals such as water temperature trigger spawning. SPAWNING OR MATING - Bringing gametes together - Process of releasing the eggs and sperm or deposited into water by aquatic animals. GAMETOGENESIS - Production of gametes - Process of formation and development of gametes OOGENESIS- production of eggs SPERMATOGENESIS- production of sperms What are the different ways of asexual reproduction in animals? Budding Fragmentation Fission Spore formation BUDDING - Organisms reproduce by having new individuals split off from existing ones, which results in genetically identical parent and daughter organisms. - The bud may stay attached or break free from the parent. - Another method, where a new organism develops from an outgrowth from the parent body known as a bud. These derive nutrition from the parent for growth and development. Once grown, the new organism detaches from the parent body. - Hydra FRAGMENTATION - This type asexual reproduction is exhibited by Planaria. In this the parent body breaks into several pieces where each piece grows into a new individual. The detachment of the body is intentional. - Fragmentation s multicellular organisms is a form of asexual reproduction in which an organism is split into fragments. Each of these fragments develops into matured, fully grown individuals that are identical to their parents. - Multicellular organisms. REGENERATION - Is a type of asexual reproduction in which the organism is capable of re growing certain body parts. - Process when an organism regrows or regenerates a lost body parts. BINARY FISSION - Is a type of asexual reproduction in which the fully grown parent cell splits into two halves, producing two new daughter cells. It is common among organisms such as bacteria, amoeba, and paramecium. - Parent cell divides into two equal parts each containing a nucleus. These are called daughter cells. The daughter cells are genetically and physically similar to the parent cell.  PARTHENOGENESIS - Is a form of asexual reproduction where an egg develops into a complete individual without being fertilized. - Parthenos- virgin ; genesis- birth - Some species like flatworms, roundworms annelids, crustaceans, insects, fishes, and some reptiles can reproduce through this process.  a type of asexual reproduction in which the female gamete develops into the offspring without being fertilized by a male gamete. it is also referred to by many as “virgin birth”. SPORE FORMATION - Found in non flowering plants such as fungi and bacteria. In this method of reproduction, the parent plant produces hundreds of tiny spores which can grow into new plants. SPORANGIA- spores just like seeds; specialized reproductive structures. The spores are dispersed via wind and grow into new organisms. Plants that reproduce by spores – ferns, mosses, liverworts and green algae. VEGETATIVE REPRODUCTION - Is a form of asexual reproduction of a plant. - Only one plant is involved and the offspring is the result of one parent. - The new plant is genetically identical to the parent. - It occurs when new individuals are formed without the production of seeds or spores. -  VEGETATIVE is a word that comes from vegetation and refers to plants or parts of a plant. PROPAGATION is the breeding or making offspring in plants or animals. VEGETATIVE PROPAGATION can be described as the process of making new plants from a parts( stems, leaves or other structure)of the parent plant. - POTATOES ONIONS GINGERS STRAWBERRY BRYOPHYLLUM FEATURES OF ASEXUAL REPRODUCTION 1.NO FORMATION OF GAMETES OR FETILIZATION TAKES PLACE 2.ONLY ONE PARENT IS INVOLVED 3.THE PROCESS OCCURS IN VERY LESS TIME 4.THE OFFSPRING PRODUCED ARE EXACT COPIES OF THE PARENT, THERE IS NO VARIATION 5.THE GROWTH OF THE OFFSPRING IS RAPID.