Students can go through AP State Board 8th Class Biology Notes Chapter 4 Reproduction in Animals to understand and remember the concept easily.
AP State Board Syllabus 8th Class Biology Notes Chapter 4 Reproduction in Animals
→ Animals that lay eggs are called oviparous. E.g. Hen, Duck, Crow, Pigeon
→ Animals that lay eggs do not have epidermal hair or external ears.
→ Animals that give birth to their offspring are called viviparous. These animals have epidermal hair on their skin and external ears.
→ The Asexual Reproduction takes place in Hydra is by Budding.
→ Reproduction without the fusion of gametes is called Asexual Reproduction.
→ The Asexual Reproduction in which an animal reproduces by dividing into two individuals is called Binary Fission.
→ Sexual Reproduction is the fusion of the male reproductive cell with the female reproductive cell.
→ A zygote is formed by the fusion of the female reproductive cell or ovum and the male reproductive cell or sperm.
→ The male reproductive system includes a pair of Tests, two seminal ducts and a Penis. % Female reproductive system contains a pair of ovaries, oviducts (also called fallopian tubes) and uterus.
→ The fusion of the male game (sperm) and the female game (ovum) is called fertilization. This results in the formation of fertilized egg or zygote.
→ The embryo continues to develop in the uterus.
→ The period (about 270 – 280 days) a baby is born is called the gestation period.
→ From the 3rd month of pregnancy, the embryo is called the foetus.
→ Fertilization that takes place inside the body of the female is called Internal fertilization. E.g.: Human beings, animals.
→ Fertilization that takes place outside the female body is called External Fertilization. E.g. Fish, frogs, Starfish, etc.
→ The marked changes that take place during the development of tadpole larva to adult are called metamorphosis.
→ The animals which carry both male and female reproductive organs are called ‘Bisexual animals’ also called Hermaphrodites.
→ Cloning is the production of an exact copy of a cell, any other living part, or a complete organism.
→ Reproduction: The ability of an organism (plant or animal) to produce a new generation of individuals of the same species is called Reproduction.
→ Budding: Hydra, a microscopic organism reproduces asexually. Buds are formed on the body surface. These buds separated from the hydra and develop into a new individual. This type of asexual reproduction is called Budding.
→ Uterus: It ¡s a part of the female reproductive system. This is a strong muscular sac, where the embryo develops into a baby.
→ External fertilization: The process of fertilization that occurs outside of an organism is called external fertilization.
→ Pregnancy: The period from zygote to the fully developed foetus is called pregnancy.
→ Zygote: Fertilization results in the formation of a zygote.
→ Binary fission: A type of asexual reproduction in which an animal reproduces by dividing into two individuals is called Binary Fission.
→ Ovary: A part of ovaries lie inside the abdomen in the hip region of the female body, one on each side of the uterus.
→ Internal fertilization: Fertilization that takes place inside the body of the female animal is called internal fertilization.
→ Embryo: The zygote divides repeatedly to give rise to a ball of cells. These cells develop into different tissues and organs in the body. This developing structure is termed an embryo.
→ Testes: The male reproductive organs include a pair of testes which are egç shaped and produces the male gametes called sperms.
→ Epidermal hairs: The hair that grows on the skin (outer layer of the skin) is called epidermal hairs.
→ Foetus: From 3 months (12 weeks) of pregnancy the embryo is called a foetus.
→ Oviparous: The animals which lay eggs are called oviparous. E.g. Hen, Frog.
→ Sperms: Testes produce millions of male gametes called sperms or male gametes.
→ Fertilization: The fusion of male (sperm) garnet and female (ova) garnet is called fertilization.
→ Bisexual animals: Some animals carry both male and female reproductive organs. Such animals are called bisexual animals also called hermaphrodites.
→ Viviparous: The animals which give birth to young ones are called viviparous.
→ Ova: The ovary produces female gametes called ova or egg. Ova is a single cell surrounded by an outer covering and a nucleus floating in the cytoplasm.
→ Asexual reproduction: New individuals are formed without the fusion of gametes. This process is called Asexual reproduction.
→ Sexual reproduction: New individuals are formed with the fusion of male and female gametes. This process is called sexual reproduction.
→ Metamorphosis: Transformation of the larva into an adult through drastic changes is called metamorphosis.
→ Offsprings: Mother gives birth to the new individuals (baby) after fertilization is called offsprings.
→ Test tube babies:
You might have heard that in some women oviducts are blocked. These women are unable to bear babies because sperm cannot reach the eggs for fertilization. In such cases, doctors collect freshly released eggs and sperms and keep them together for few hours for IVF or in vitro fertilization (fertilization outside the body). In case fertilization occurs, the zygote is allowed to develop for about a week and then it is placed in the mother’s uterus. Complete development takes place in the uterus and the baby is born like any other baby. Babies born through this technique are called test-tube babies. This term is actually misleading because babies cannot grow in test tubes.
→ Some animals like earthworms are neither male nor female. They carry both male and female reproductive organs. Such animals are called “bisexual animals” (also called hermaphrodite).
→ A.P.J. Abdul Kalam:
Avul Pakir Jainulabdeen Abdul Kalam (born 15th October 1931 – died 27th July 2015) usually referred to as Dr A.P.J.Abdul Kalam is an Indian administrator, who served as the 11th President of India from 2002 to 2007. Kalam was born and raised in Rameswaram, Tamil Nadu, studied Physics at St. Joseph’s College, Tiruchirapalli and Aerospace Engineering at the Madras Institute of Technology, Chennai.
Before his term as President, he worked as an aerospace engineer with Defence Research and Development and Indian Space Research organisation. Kalam is popularly known as the Missile Man of India for his work on the development of ballistic missiles and launch vehicle technology. He played a pivotal organisational, technical and political role in India’s Pokhran-II nuclear tests in 1998, the first since the original nuclear test by India in 1974. Some scientific experts have however called Kalam a man with no authority over nuclear physics but who just carried on the works of Homi J.Bhabha and Vikram Sarabhai
Kalam was elected the President of India in 2002, defeating Lakshmi Sahagal and was supported by both the Indian National Congress and the Bharatiya Janatha Party, the major political parties of India. He is currently a visiting professor at the Indian Institute of Management Ahmedabad and Indian Institute of Management Indore, Chancellor of the Indian Institute of space science and Technology, Thiruvananthapuram, a professor of Aerospace Engineering at Anna University (Chennai).
Kalam advocated plans to develop India into a developed nation by 2020 in his book India 2020. He has received several prestigious awards including the Bharata Ratna, Indies highest civilian honour. He launched his mission for the youth of the nation in 2011 called the what can I give movement with a central theme to defeat corruption in India.
A.RJ. Abdul Kalam’s 79th birthday was recognised as World Student’s Day by United Nations. He has also received honorary doctorates from 40 universities. The Government of India has honoured him with the Padma Bhushan in 1981and the Padma Vibhushan in 1990 for his work with ISRO and DRDO.