The Living Environment
“Observe and describe the variations in reproductive patterns of organisms, including asexual and sexual reproduction.”
In order for an organism to survive it must reproduce. Some organisms reproduce sexually while others reproduce asexually. Some organisms have the ability to reproduce both sexually and asexually.
Asexual reproduction comes in many forms:
- Fission- is the splitting of a single celled organism into two equal parts. Each part has identical genetic information and will grow to be a new organism. An ameba will reproduce by the process of fission. The genetic material will replicate and then the cell membrane will pinch in to create two organisms instead of one.
- Budding- is the splitting of a single celled organism into two genetically equal parts. The cell material, such as cytoplasm, is not equal. The new organism is much smaller than the parent. This new organism will grow to be a full size organism.
- Vegetative Propagation- is when a plant branches off and becomes a new plant. The new plant is much smaller than the parent but will grow and develop into a mature plant. Examples include: bulbs, rhizomes, tubers and runners.
- Cloning- is the process of replicating genetic information. Scientist can take an organism such as a carrot and by cloning make new carrots by copying the genetic information in the lab.
Sexual reproduction involves two sets of genetic information, that from the male and from the female. Methods of sexual reproduction vary from organism to organism. The joining of two cells (each with ˝ of the genetic information) will then create the genetic information to produce a new organism. The male sperm cell must fertilize the female egg cell in order for this process to be complete. Fertilization can occur either inside (internal) or outside (external) of the female. The fertilized egg, zygote, contain ˝ of the genetic information from the female and ˝ from the male. Offspring from sexual reproduction are not genetically identical to either parent.
Index
Performance Indicator Key
Living Environment
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1.2
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2.1
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2.2
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3.1
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3.2
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4.1
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4.2
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4.3
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4.4
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5.1
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5.2
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6.1
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6.2
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7.1
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7.2
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Physical Setting
Vocabulary
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2.1
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2.2
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3.1
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3.2
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3.3
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4.1
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4.2
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4.3
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4.4
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4.5
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5.1
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5.2
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