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Reproduction. Bell ringer: Name and explain 1 thing that may increase the risk of cancer. Reproduction. All organisms, like these animals, need to reproduce. Reproduction. There are two kinds of reproduction: sexual and asexual
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Reproduction Bell ringer: Name and explain 1 thing that may increase the risk of cancer.
Reproduction • All organisms, like these animals, need to reproduce
Reproduction • There are two kinds of reproduction: sexual and asexual • Sexual reproduction produces offspring that are different from the parents • Asexual reproduction produces offspring that are genetically identical to the parents
Asexual reproduction • In asexual reproduction, the offspring are identical to the parent. They are known as clones • Much like BobaFett and JangoFett from Star Wars
Kinds of Asexual Reproduction • One way organisms reproduce asexually is actually mitosis. • Bacteria do a similar process but we call it binary fission.
Kinds of Asexual Reproduction • Budding is when the parent grows a genetically identical offspring on its body, and then the offspring breaks away
Kinds of asexual Reproduction • Regeneration occurs when an offspring grows from a piece of the parent.
Kinds of asexual reproduction • Vegetative reproduction is a form of asexual reproduction in which offspring grow from a part of a parent plant.
Kinds of asexual reproduction • Cloning is a type of asexual reproduction performed in a laboratory that produces identical individuals from a cell or from a cluster of cells taken from a multicellular organism. • Scientists have been able to clone many animals with the chromosomes from one parent.
Asexual reproduction Advantages Disadvantages Can result in harmful mutations No variation (everything is identical) so if there are bad genes they are constantly passed on • No mate necessary • Saves time and energy • Can produce large numbers of offspring all at once
Brain pop! • http://www.brainpop.com/science/cellularlifeandgenetics/asexualreproduction/preview.weml
Sexual Reproduction Bell Ringer: name an advantage or disadvantage of asexual reproduction
Sexual Reproduction • In sexual reproduction, a female and male sex cell come together • The female sex cells are called eggs • The male sex cells are called sperm
Sexual Reproduction • Fertilization is the process through which the sperm and egg join. • When the sperm joins with the egg they create something called a zygote
Diploid cells • Organisms that reproduce sexually form body cells (muscle, bone, etc.) and sex cells (sperm and egg) • In body cells of most organisms, similar chromosomes occur in pairs. • Diploid cells are cells that have pairs of chromosomes. • All cells in your body are diploid except for sperm and egg
Diploid cells • Pairs of chromosomes that have genes for the same traits arranged in the same order are called homologous chromosomes. • Because one chromosome is inherited from each parent, the chromosomes are not identical. • Different organisms have different numbers of chromosomes.
Haploid cells • Some cells have only half the number of chromosomes. These are haploid cells. • In your body only the sperm and egg cells are haploid. • When two haploid sex cells meet, they form a diploid zygote.
Sexual reproduction Advantages Disadvantages Organisms have to grow and develop until they are mature enough to produce sex cells. Organisms must form sex cells—either eggs or sperm. • Genetic variation • Due to genetic variation, individuals have slight differences. • Genetic variation may enable organisms to be more disease-resistant, or stronger or have some other advantage over another member of the same species.
Review • Which of these is not a kind of asexual reproduction? • Budding • Cloning • Fertilization • Vegetative Reproduction
review • What is an advantage of asexual reproduction? • Genetic variation occurs • No need for a mate • Selective breeding is possible • Use of sperm and egg
review • A cell with pairs of chromosomes, one from the mother and one from the father is known as: • Diploid cell • Gametes • Haploid cell • Sex cell
review • When sperm and egg come together, they form a: • A new egg cell • Haploid cell • Sex cell • Zygote