Genetic Variation Study Guide (8th Grade) PDF

Name _________________________ Genetic Variation Study Guide (8th) Vocabulary: asexual reproduction - The process of producing a new organism using just one parent. binary fission - This is how prokaryotes divide. The D...

Name _________________________ Genetic Variation Study Guide (8th) Vocabulary: asexual reproduction - The process of producing a new organism using just one parent. binary fission - This is how prokaryotes divide. The DNA is replicated and the cell elongates. The DNA molecules move to opposite poles before the cell divides. Example. E. coli Budding - This is when there is increased cell division at one site on an organism. It grows and eventually breaks off to become its own new individual. Examples: hydra, yeast. Fragmentation - This is when a part of a mature organism breaks off and develops on its own to become a new organism. Examples include fungi, sea sponges, star fish. Identical - having such close resemblance as to be essentially the same Regeneration - renewal or restoration of a body, bodily part vegetative propagation - This is when plants produce new individuals directly from the parent organism. Examples: runners in strawberry plants and plantlets in spider plants. Dominant - commanding, controlling, or prevailing over all others. Embryo - the name given to an unborn baby from the time of fertilization until eight weeks of development fertilization [external, internal] - the joining of an egg and a sperm Gamete - an organism's reproductive cells Genetic - The study of how genes and how traits are passed down from one generation to the next Variation - any difference between cells, individual organisms, or groups of organisms Heterozygous - A term that describes having two different versions of the same gene Homozygous - having inherited the same versions (alleles) of a genomic marker from each biological parent Mitosis - the process by which a cell replicates its chromosomes and then segregates them, producing two identical nuclei in preparation for cell division Punnett square - a square diagram that is composed of a grid of usually four boxes and is used to calculate and depict all the combinations and frequencies of the different genotypes and phenotypes among the offspring of a cross in accordance with Mendelian inheritance Recessive - a trait that tends to be masked by other inherited traits sex cell - reproductive cells or gametes sex-linked gene - characteristics (or traits) that are influenced by genes carried on the sex chromosomes Sexual Reproduction - The process of producing a new organism using two parents. Zygote - fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm) 1. I can explain the requirements for asexual reproduction. Single parent involved. No fertilization or gamete formation takes place. This process of reproduction occurs in a very short time. The organisms multiply and grow rapidly. The offspring is genetically similar. 2. I can explain why asexual reproduction creates offspring that are genetically identical to the parent. a. the offspring are all clones of the original parent 3. I can make generalizations about the types of organisms that tend to asexually reproduce. a. Sea stars: These organisms reproduce by fission. b. Hydra: They reproduce by budding. c. Yeast: These organisms reproduce by budding. d. Paramecium: They produce offspring by binary fission. e. Stick insects: They use the mode of parthenogenesis sometimes to reproduce. 4. I can explain advantages/disadvantages of asexual reproduction a. relatively quick b. offspring receive good traits c. less ability to adapt to the environment d. offspring receive bad traits 5. I can explain the process of binary fission using examples of organisms that use binary fission to asexually reproduce. a. This is how prokaryotes divide. The DNA is replicated and the cell elongates. The DNA molecules move to opposite poles before the cell divides. Example. E. coli 6. I can explain the process of vegetative propagation using examples of organisms that use vegetative propagation to asexually reproduce. a. This is when plants produce new individuals directly from the parent organism. Examples: runners in strawberry plants and plantlets in spider plants. 7. I can explain the process of fragmentation using examples of organisms that use fragmentation to asexually reproduce. a. This is when a part of a mature organism breaks off and develops on its own to become a new organism. Examples include fungi, sea sponges, star fish. 8. I can explain the process of regeneration using examples of organisms that use regeneration to asexually reproduce. a. This is when a part of a mature organism breaks off and develops on its own to become a new organism. Examples include fungi, sea sponges, star fish. 9. I can explain the process of budding using examples of organisms that use budding to asexually reproduce. a. This is when there is increased cell division at one site on an organism. It grows and eventually breaks off to become its own new individual. Examples: hydra, yeast. 10. I can explain the requirements for sexual reproduction including types of organisms that engage in sexual reproduction (more complex organisms). a. The process of producing a new organism using two parents. Examples: Humans, animals, etc. 11. I can explain how sex cells (gametes; sperm and eggs) contain DNA in the form of chromosomes. a. Sperm and egg cells are both haploid which means they have half as many chromosomes as a body cell. 12. I can explain the difference between internal and external fertilization. a. Internal fertilization is the process when the syngamy (union of male and female gamete) occurs inside the female body after insemination using copulation. In contrast, External fertilization is the syngamy outside the female body, that is in the outer environment especially in water bodies. 13. I can explain how, after fertilization, a zygote undergoes mitosis. a. The zygote undergoes divisions that increase the number of cells in the zygote. 14. I can explain what percentage of an offspring’s DNA is inherited from the mother and father in sexual reproduction. a. In sexual reproduction, organisms inherit half of their nuclear DNA from the male parent and half from the female parent. 15. I can explain ways in which sexual reproduction results in genetic variation. a. The process of sexual reproduction introduces variation into the species because the alleles that the mother and the father carry are mixed together in the offspring. 16. I can explain advantages of sexual reproduction a. genetic variation and ability to adapt to the environment 17. I can explain how genetic variation contributes to a species’ survival. a. Maintaining high genetic diversity allows species to adapt to future environmental changes and avoid inbreeding. 18. I can explain disadvantages of sexual reproduction a. Energy required to mate and to have and care for a baby 19. I can compare the processes for how plants and animals reproduce. a. Different plants and animal can reproduce either asexually or sexually; however, asexual reproduction is more common among plants than animals 20. I can explain how sex-linked genes manifest differently in female and male offspring. a. X-linked genes have distinctive inheritance patterns because they are present in different numbers in females (XX) and males (XY) 21. I can use a Punnett square to determine the probability that a specific trait will be expressed. a. Determine the genotypes of the parents. b. Write down the possible gametes for each parent. c. Arrange the parents' gametes around the edges of a Punnett square. d. Fill out the offspring squares. e. Interpret the results. 22. Explain how asexual reproduction results in offspring with identical genes a. For example, compare the different methods for asexual reproduction, and explain why each results in offspring with identical genetic information to their parents. 23. Explain how sexual reproduction results in offspring with genetic variation a. For example, explain the process for sexual reproduction in humans, and use Punnett squares to predict the probability of traits being passed down from parents to offspring.