TST CURATION ASSIGNMENT Reproduction in vertebrates

Reproduction in vertebrates

1. Sexual Reproduction in Vertebrates. Presented by Lekokotla Kgothatso [email protected]

2. Understanding the reproductive processes of vertebrates Welcome to the fascinating world of sexual reproduction in vertebrates What are veterbrates ? How do vertebrates reproduce? What are the advantages and disadvantages of different reproctive strategies in vertebrates? Let us find out!! [Figure 1]

3. What are vertebrates? Vertebrates are animals with a backbone/spinal column that plays an important role in supporting the structure of the body (Muhammed, 2015). They are characterized with: An internal skeleton Head, tail, bilateral symmetry Heart with chambers Skin, scales, feathers or fur. Joints and limbs (in most vertebrates) [Figure 2]

4. Reproductive strategies Ovipary Females lay eggs outside their bodies and eggs develop and hatch outside. External development Examples: Birds, reptiles, amphibians (ANGELINI & GHIARA, 1984). Ovovivipary Females develop eggs inside their bodies and the egges hatch inside. Internal egg development Exampls : some snakes, lizards and fish (ANGELINI & GHIARA, 1984). Vivipary Females nourish developing young inside their bodies an the young is born to be taken care by the mother. Internal embroyic development Examples:mammals some fish and snakes (ANGELINI & GHIARA, 1984).

5. Sexual reproduction(Fertilization in vertebrates)

6. Continuation…

7. Gamates & Reproductive Organs Gamates are the sex cells that combine during fertilization (Muhammed, 2015). Reproductive organs are the body parts that produce and support gamates (Muhammed, 2015). Gamates Sperm (male gamete) Egg (Female gamate ) Reproductive organs Male [Testes (produces sperm) & Penis (delivers spem ) Female [ovaries-produce eggs & uterus-nurtures developing offspring]

8. Fertilization and Genetic Diversity Fertilization refers to the joining of both male and female gamete which is an egg and sperm to form a zygote ( O’Rand , 1986). Process

9. Genetic Diversity It refers to variety of genetic information within a population or species (Garner et al, 2004). We have mechanisms/processes that contribute to genetic variation. Crossing Over There is an exchange of genetic material. It occurs during meiosis It is influenced by genetic factors Essential for sexual reproduction (Muhammed, 2015). [Figure 3]

10. Continuation….. 2. Meiotic Recombination It shuffles genetic material Occurs during meiosis Involves crossing over and gene (Muhammed, 2015). [Figure 4]

11. Continuation… 3. Mutation It occurs randomly Can be passed on to offspring Alter DNA sequence (Muhammed, 2015). [Figure 5]

12. Types of reproductive strategies Parthenogenesis Type of reproductionwhere an offspring growns without a male parent. The female parent produce an offspring on her own without fertilization. Examples: insects,aphids (Muhammed, 2015). [Figure 6]

13. Continuation… Hermaphroditism When an individual has both male and female reproductive part Can produce both sperms and eggs Can fertilize themselves or mate another individual (Muhammed, 2015). [Figure 7]

14. Advantages and Disadvantages of Sexual Reproduction Advantages Mix og genes from two parents creates astronger unique baby. Genetic diversity helps offspring adapt and survive better. Different genes reduce the risk of inherited diseases. Helps species adapt to changing environments (Muhammed, 2015). Disadvantages It is time consuming Requires finding a suitable mate for reproduction Unequal distribution of genes to offspring. Higher risks of getting infections from the other mate (Muhammed, 2015).

15. Thee end !

16. Reference List Muhammed, B (2015). Sexual reproduction in vertebrates. Available from : https://www.slideshare.net/slideshow/sexual-reproduction-in-vertebrates/145624374 ( Accessed 15 May 2019). Angelini, F., & Ghiara , G. (1984). Reproductive modes and strategies in vertebrate evolution. Italian Journal of Zoology, 51(1-2), 121-203. Long, J. A., Trinajstic , K., & Johanson, Z. (2009). Devonian arthrodire embryos and the origin of internal fertilization in vertebrates. Nature, 457(7233), 1124-1127. O’Rand , M. G. (1986). Steps in the fertilization process: Understanding and control. The Molecular and Cellular Biology of Fertilization, 383-393. Garner, T. W., Pearman, P. B., & Angelone , S. (2004). Genetic diversity across a vertebrate species’ range: a test of the central–peripheral hypothesis. Molecular Ecology, 13(5), 1047-1053.Chicago Figure1.n.dhttps://images.app.goo.gl/ynKJjrxs5gPpmrxQ6 Accessed (15 July 2013) Figure2.n.d https://images.app.goo.gl/cP35Ttg8V7gyqa3W8 Accessed (30 July 2024) Figure3.n.d https://images.app.goo.gl/pHeDGXKGYBA2Jb877 Accessed (14 May 2022) Figure4.n.d https://images.app.goo.gl/N32s9ZxbHJqb6s8MA Accessed (18 October 2013) Figure5.n.d https://images.app.goo.gl/1UZ6cZFHqcR8F5yW7 Accessed (14 May 2016) Figure5.n.d https://images.app.goo.gl/2t2cPfAsUmxSvdHD6 Accessed (11 July 2021) Figure6.n.d https://images.app.goo.gl/1YzThWP2LrZaXSsBA Accessed (20 November 2020)