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a. Asexual reproduction
- i. Offspring are genetic copies
- ii. Single parent who passes copies of all genes to offspring without fusion of gametes
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Do eukaryotic organisms carry out asexual reproduction? Explain.
- 1. Eukaryotic organisms do this by mitotic cell division, resulting in tow equally identical daughter cells
- 2. Multicellular organisms:
- a. Genetically identical= clone, a group of genetically identical individuals
- ii. Genetic differences occasional due to mutations
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Sexual reproducton
- i. Two parentsà offspring with combo of genes from both parents
- 1. Unlike clones, they vary genetically, not exact replicas
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a. __= generation-to-generation sequence of stages in reproductive history of an organism, from conception to production of its own offspring
Life cycle
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Types of Cells and number
- somatic (46/ 2 sets of 23)
- gametes (23/ one set)
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i. Somatic
1. Become condensed in __, distinguished from one another by __, __, and __ produced by certain stains
- mitosis
- size, positions of centromeres, pattern of colored bands
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1. __
a. Images of chromosomes arranged in pairs, starting with __chromosomes
i. Pairs have same __= homologous chromosomes
1. Both chromosomes of each pair carry genes controlling same inherited characters
- Karyotype
- longest
- length, centromere position, and staining pattern
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i. Sex chromosomes (autosomes)
1. Distinct __ and __
a. Human females have __
b. Human males have __
i. Only small parts of __ and __ are __
1. Most genes carried on X are not present in Y, and vice versa
- X and Y
- homologous pair of X (XX
- one X and one Y (XY)
- X and Y
- homologous
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i. Number
1. Inheritance of one chromosome of each pair form each parent= __in human somatic cells
a. __sets of __—__and __
2. Number of chromosomes in a single set is designated __
a. Two sets= __(2n= 2(23)= 46 in humans)
- 46
- Two
- 23
- maternal
- paternal
- n
- diploid
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1. __are the gametes= one n
a. Humans have __
i. 22 __and a single __
1. Egg contains __; sperm may have __
2. Species have different haploid and diploid numbers
- Haploid
- 23
- autosomes
- sex chromosome
- X
- X or Y
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a. Behavior in Human Life Cycles
- i. Haploid sperm+ haploid egg (fertilization)= fertilized egg (diploid zygote)
- 1. Mitosis of zygote and descendents generates somatic cells of the body
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i. Cells not produced by mitosis are __, which develop from __cells in the __
1. Use __
a. Reduces number of sets of chromosomes from two to one in gametes, counterbalancing the doubling that occurs at __
- gametes
- germ
- gonads
- meiosis
- fertilization
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i. In animals, meiosis only in __cells
1. Each human egg and sperm is __-->fertilization results in __-->mitosis
ii. Fertilization and meiosis important in sexual reproduction in plants, fungi, and protists too
1. Alternate in sexual life cycles, maintaining a constant number of chromosomes in each species from one generation to the next
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