Reproduction is the process by which living organisms produce other organisms of the same kind. Asexual reproduction is a type of reproduction where only one parent is involved and the offspring are genetically identical to the parent. Sexual reproduction is a type of reproduction where two parents produce offspring that are not genetically identical to the parents. A gamete is a sex cell. The fusion of gametes is called fertilisation. Most species of animal can only reproduce sexually. Many plants can reproduce sexually and asexually. Clones are offspring which are genetically identical to the parent organism. The characteristics of an individual are affected by both genetic factors and environmental factors. Genes are described as being either dominant or recessive. The different ways that these genes can be passed on from parents to offspring can be explored using a punnett square. The differences between individuals of the same species are called variations.
Questions and Exercises K C
Key Concepts Rewrite the following sentences in your copybook and fill in the blanks. 1. The type of reproduction that involves only one parent is called __________________ reproduction.
2. The type of reproduction that involves two parents is called __________________ reproduction.
3. A __________________ is a sex cell. 4. When two gametes fuse they form a cell called a __________________. 5. The process by which two gametes fuse is called __________________. 6. An organism that is composed of only one cell is called __________________. 7. A multicellular organism is composed of __________________ cells. 8. The structures inside our cells that contain genes are called __________________.
K U
Knowledge and Understanding 1. Explain how a zygote develops into a new individual.
2. The offspring from sexual reproduction are similar to both of their parents but are not identical to either of them. Explain why this is the case.
