Name: ___________________________ Core: __________ Date: _____________ REPRODUCTION UNIT TEST – STUDY GUIDE! Define the following terms: 1. Centrioles: an organelle that helps coordinate cell division; sends out spindle fibers during cell division. 2. Centromere: place on a chromosome that connects two sister chromatids. 3. Gonad: reproductive organs, including testes that produce sperm (male) and ovaries that produce eggs (female). 4. Haploid: a cell that contains one half of the chromosomes (n); sperm and eggs are haploid. 5. Diploid: a cell that contains a full set of chromosomes (2n); non-sex cells are diploid. 6. Zygote: the first diploid cell of a new organism (when a sperm and egg unite). 7. Carcinogen: chemicals that can damage DNA and interfere with a cell’s normal cycle. 8. Cancer: uncontrolled cell growth that results in tumors. 9. Replication: process in which an extra copy of DNA is made. 10. Gamete: a haploid sex cell, such as a sperm or egg. 11. Draw a picture of a chromosome below, circle a sister chromatid and draw an arrow to the centromere. Name: ___________________________ Core: __________ Date: _____________ ASEXUAL REPRODUCTION 12. How many parents are involved in asexual reproduction? 1 parent creates a genetic clone of themselves (passes on all of the same DNA and traits) 13. What is budding? Give an example. A type of asexual reproduction in which the offspring grows out of the body of the parent. Example: yeast, hydra 14. What is binary fission? Give an example. A type of asexual reproduction in which one parent cell splits in half to produce two genetically identical daughter cells. Example: bacteria, Euglena, Paramecium, Amoeba 15. What is fragmentation? Give an example. A type of asexual reproduction in which a piece of the parent breaks off and this piece produces a new offspring. Example: star fish, coral, plant cuttings 16. What are the advantages to asexual reproduction? a) Don’t have to find a mate (no need to spend that extra time and energy) b) Very quick type of reproduction c) Produces a lot of offspring if the conditions are right d) **Offspring have the same genetics 17. What is the disadvantage to asexual reproduction? Why is this a disadvantage? **OFFSPRING HAVE THE SAME GENETICS, WHICH MEANS THEY HAVE THE SAME TRAITS AND THE SAME DNA. This is bad because we live in a changing environment. If a certain species have the same DNA and the same traits, then they also have the same weaknesses and the same intolerances. They will all be affected by the change in the same way (none of them have a greater survival advantage). Also, an organism that creates a genetic clone of themselves will also pass on all of the same “bad” traits, including certain disorders, diseases, intolerances, and harmful mutations. SEXUAL REPRODUCTION 18. How many parents are involved in sexual reproduction? 2 parents (1 male contributes sperm; 1 female contributes an egg) leads to genetic variation!! 19. What is external fertilization? Also, give an example. External fertilization is a type of sexual reproduction in which fertilization occurs outside of the female. It usually requires a medium such as water, which the sperms can use to swim towards the egg cell. External fertilization usually occurs in fish and amphibians. Name: ___________________________ Core: __________ Date: _____________ 20. What is internal fertilization? Also, give an example. A type of sexual reproduction in which fertilization occurs within the female. • Internal fertilization occurs in mammals, insects, birds, reptiles. – Mammals (gorillas, lions, elephants, rats, zebras, and dolphins have live births) – Insects, birds, reptiles lay eggs 21. What is pollination? • Pollination occurs when pollen is produced in the male organ of the flowers and transferred to the female organs by wind or by animals. • If the female stigma is receptive to a pollen grain, the pollen produces a pollen tube, which grows through the female tissue to the egg, where fertilization takes place by the sperm nucleus. 22. What is the great ADVANTAGE to sexual reproduction? Why is this an advantage? Offspring from sexual reproduction are a combination of their parents (they have traits from both!) More diversity (differences) in the species means that they are better able to adapt to changes in the environment! Genetic diversity also reduces the likelihood of inheriting “bad” traits. *Disorders & Diseases *Intolerance to certain conditions 23. What are the disadvantages to sexual reproduction? a. Have to spend time and energy finding a mate, which also means more time exposed to predators and other risks and less time for other pursuits, such as finding food and shelter. b. Because there is genetic variation in the population, not every potential mate is as good as another. The organism therefore has to spend more time and effort selecting the appropriate mate. 24. Compare METAPHASE IN Mitosis, Meiosis I, and Meiosis II in the table below (imagine that there were FOUR chromosomes in the first prophase). Metaphase in MITOSIS Metaphase 1 in Meiosis 1 Metaphase 2 in Meiosis 2 Single file in the middle of the cell. Double file in the middle of the cell. Single file in the middle of the cell (there are now ½the Draw a picture: How is it lining up? Name: ___________________________ Core: __________ Date: _____________ amount of chromosomes; haploid). ` How many chromosomes are there? 4 4 2 25. Compare ANAPHASE IN Mitosis, Meiosis I, and Meiosis II in the table below (imagine that there were FOUR chromosomes in the first prophase). Anaphase in MITOSIS Anaphase in MEIOSIS 1 Anaphase in MEIOSIS 2 Draw a picture: What is being separated? The sister chromatids are being pulled to opposite sides of the cell. How many chromosomes are there? 4; diploid The pairs of chromosomes are separating and each whole chromosome is moving to opposite sides of the cell. 4; diploid The sister chromatids are being moved to opposite sides of the cell (there is a haploid number now). 2; haploid 26. What are the stages of the cell cycle that lead to the production of 2 daughter cells with the same DNA as the parent (MITOSIS)? Interphase Prophase Metaphase Anaphase Telophase Cytokinesis MITOSIS = (Prophase, Metaphase, Anaphase, Telophase) 27. What is the goal of Mitosis? Goal of mitosis is to produce 2 daughter cells that are genetically identical to the parent (same DNA). -Used for growth -1 set of divisions -1 diploid cell 2 diploid cells 28. What are the stages of Meiosis (Meiosis 1 & 2)? Name: ___________________________ Core: __________ Date: _____________ ProphaseI MetaphaseI Anaphase I Telophase I (& Cytokinesis) Prophase II Metaphase II Anaphase II Telophase II (& Cytokinesis) 29. What is the goal of Meiosis? Goal of Meiosis: to produce sperm or eggs, also called gametes; contains ½ the genetic information as the parent. -Used for reproduction -2 sets of division -1 diploid cell 4 haploid cells 30. What disease did the Tasmanian Devils have, how did they get it, and how is this related to genetic variation? Devil facial tumor disease; the Tasmanian Devils would fight each other and as a result, cancer cells would move from one devil to the other because there was such low genetic variation in the population. The devil’s body would not recognize the cancer cells from another devil as “foreign” and the immune system would not destroy it. You can’t catch cancer from someone else, because there is a lot of genetic variation in humans and your body would recognize foreign cancer cells (from someone else) and destroy them. 30. Label each of the stages of the cell cycle below. 31. What is crossing over and when does it occur? Crossing over occurs in Prophase 1 of Meiosis 1 and involves a process where genetic material is traded between two homologous chromosomes, which leads to greater genetic variation in the offspring.