Selection
Muhtasari
Why do bacteria stop responding to antibiotics? Why do farm animals and crops look so different from their wild ancestors? The answer to both is selection: in nature the environment does the choosing, while in farming humans do. The same basic mechanism, some individuals leaving more offspring than others, drives both.
In this lesson you will describe natural selection step by step, describe and apply selective breeding to crops and livestock, and (for Extended) define adaptation, explain antibiotic resistance as natural selection in action, and contrast natural with artificial selection.
Malengo
- Describe natural selection with reference to: (a) genetic variation within populations (b) production of many offspring (c) s truggle for survival, including competition for resources (d) a greater chance of reproduction by individuals that are better adapted to the environment than others (e) these individuals pass on their alleles to the next generation
- Describe selective breeding with reference to: (a) selection by humans of individuals with desirable features (b) crossing these individuals to produce the next generation (c) selection of offspring showing the desirable features
- Outline how selective breeding by artificial selection is carried out over many generations to improve crop plants and domesticated animals and apply this to given contexts
- [Supplement] Describe adaptation as the process, resulting from natural selection, by which populations become more suited to their environment over many generations
- [Supplement] Describe the development of strains of antibiotic resistant bacteria as an example of natural selection
- [Supplement] Outline the differences between natural and artificial selection
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Maelezo ya Somo
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Tathmini ya Somo
Hongera kwa kukamilisha somo la Selection. Sasa kwa kuwa umechunguza dhana na mawazo muhimu, ni wakati wa kuweka ujuzi wako kwa mtihani. Sehemu hii inatoa mazoezi mbalimbali maswali yaliyoundwa ili kuimarisha uelewaji wako na kukusaidia kupima ufahamu wako wa nyenzo.
Utakutana na mchanganyiko wa aina mbalimbali za maswali, ikiwemo maswali ya kuchagua jibu sahihi, maswali ya majibu mafupi, na maswali ya insha. Kila swali limebuniwa kwa umakini ili kupima vipengele tofauti vya maarifa yako na ujuzi wa kufikiri kwa makini.
Tumia sehemu hii ya tathmini kama fursa ya kuimarisha uelewa wako wa mada na kubaini maeneo yoyote ambapo unaweza kuhitaji kusoma zaidi. Usikatishwe tamaa na changamoto zozote utakazokutana nazo; badala yake, zitazame kama fursa za kukua na kuboresha.
- In natural selection, the individuals most likely to pass on their alleles are those that are: A. the largest B. best adapted to their environment C. born first D. selected by humans Answer: B
- Selective breeding is best described as selection carried out by: A. the environment B. humans C. predators D. chance alone Answer: B
- Antibiotic resistance in bacteria first arises by: A. the antibiotic teaching the bacteria B. a chance mutation C. bacteria choosing to resist D. selective breeding Answer: B
- Which is a disadvantage of selective breeding over many generations? A. it increases variation B. it reduces genetic variation C. it is very fast D. it removes humans from the process Answer: B
- A key difference between natural and artificial selection is that artificial selection is carried out by: A. the environment B. humans C. mutation D. predators Answer: B
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Fanyia kazi maswali haya kwenye programu
Vitabu Vinavyopendekezwa
Jifunze zaidi kutoka vyanzo huria
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Sehemu ya kitabu
Understanding Evolution
Describe how the present-day theory of evolution was developed
"Biology: Understanding Evolution" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/18-1-understanding-evolution. Access for free at https://openstax.org/books/biology/pages/1-introduction
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Sehemu ya kitabu
Adaptive Evolution
Explain the different ways natural selection can shape populations
"Biology: Adaptive Evolution" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/19-3-adaptive-evolution. Access for free at https://openstax.org/books/biology/pages/1-introduction
Vimechapishwa na mashirika mengine chini ya leseni huria na vinatajwa kama wanavyoomba. Viungo hufungua tovuti zao.
Fanya Mazoezi ya Maswali ya Majaribio
Ungependa kufanya mazoezi ya maswali ya majaribio kuhusu Selection? Pakua programu ya Green Bridge CBT ili kupata maswali ya majaribio na tathmini kamili za mazoezi kuhusu mada hii.
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