Science

• sexual reproduction


  In sexual reproduction there is mixing of genetic information which leads to variety in the offspring. The formation of gametes involves meiosis
• asexual reproduction 


  Asexual reproduction involves only one parent and no fusion of gametes. There is no mixing of genetic information. This leads to genetically identical offspring (clones). Only mitosis is involved.
• how does meiosis half the number of chromosomes and fertilisation restore the full number of chromosomes 


  each gamete has half the number of the total 46 chromosomes. the egg from the mother and sperm cell from the father then fuse together to form a cell with a full number of chromosomes
• What are the two main ways that organisms can reproduce?

  Sexual reproduction and asexual reproduction
• Which organisms can reproduce through both sexual and asexual reproduction?


  Some plants
• What type of reproduction do most animals rely on?

  Sexual reproduction
• How do bacteria reproduce?


  Asexually
• What is the key point of sexual reproduction?


  It involves the fusion of male and female gametes
• What is fertilization in the context of sexual reproduction?


  The fusion of male and female gametes
• Why are offspring from sexual reproduction genetically different?


  Because they contain a mixture of their parents' genes
• How many chromosomes does a normal human cell have?


  46 chromosomes
• How many chromosomes do human gametes have?


  23 chromosomes
• What happens when two gametes fuse together?


  The resulting cell will have 46 chromosomes
• What is meiosis?


  A process that produces gametes with half the genetic material
• Does sexual reproduction have to involve sexual intercourse?


  No, it just refers to the fusion of male and female gametes
• How do plants reproduce sexually?

  By the combination of pollen and egg cells
• What is a key characteristic of asexual reproduction?


  It takes place with only one parent and does not involve gametes
• What is the result of asexual reproduction?


  All offspring are identical clones
• What type of reproduction do eukaryotic organisms like plants and fungi use?


  Asexual reproduction through mitosis
• How do bacteria reproduce asexually?


  By binary fission
• What are the differences between sexual and asexual reproduction?


  • Sexual reproduction involves two parents and gamete fusion.
  • Asexual reproduction involves one parent and no gamete fusion.
  • Sexual reproduction introduces genetic variation; asexual reproduction produces identical clones.
• What processes are involved in sexual and asexual reproduction for different organisms?


  • Sexual reproduction: fertilization, meiosis (in animals and plants).
  • Asexual reproduction: mitosis (in eukaryotes), binary fission (in bacteria).
• What is the process that forms gametes?

  Meiosis
• What are gametes sometimes referred to as?


  Sex cells
• How much genetic material do gametes contain compared to normal cells?


  Half the genetic material
• What do we call cells that contain half the genetic material?

  Haploid cells
• What happens when two gametes combine?


  They form a normal cell that can grow into a new organism
• What do we call cells that contain two sets of genetic information?

  Diploid cells
• What is the first step in meiosis?


  To replicate all of the cell's DNA
• What shape do chromosomes take after DNA replication in meiosis?


  X shape
• How many different types of chromosomes do humans have?


  23 different types
• What are the two copies of chromosomes from each parent called?


  Maternal and paternal chromosomes
• How many individual chromosomes does each human cell have?


  46 individual chromosomes
• What happens to the chromosomes during the first division of meiosis?


  The chromosome pairs are pulled apart and randomly distributed
• What is the result of the second division in meiosis?


  Four genetically unique cells
• Why are gametes considered genetically unique?


  Because of tiny changes during meiosis
• In male animals, what do the gametes develop into?

  Sperm cells
• In female animals, what do the gametes develop into?


  Egg cells
• What happens during fertilization?

  A sperm and egg fuse to form a diploid cell
• What does the diploid cell do after fertilization?


  It divides by mitosis to form an embryo