Q: Prokaryotes divide via binary fission and do not undergo what process of cell division? Read this paragraph and choose the correct option from the provided answers: Reproduction Reproduction in prokaryotes is asexual and usually takes place by binary fission. Recall that the DNA of a prokaryote exists as a single, circular chromosome. Prokaryotes do not undergo mitosis. Rather the chromosome is replicated and the two resulting copies separate from one another, due to the growth of the cell. The prokaryote, now enlarged, is pinched inward at its equator and the two resulting cells, which are clones, separate. Binary fission does not provide an opportunity for genetic recombination or genetic diversity, but prokaryotes can share genes by three other mechanisms. Choices: - prophase - meiosis - fusion - mitosis A:
mitosis
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Q: What cell structures are like storage centers and tend to be larger in plant cells? Read this paragraph and choose the correct option from the provided answers: The vacuoles are like storage centers. Plant cells have larger vacuoles than animal cells. Plants store water and nutrients in their large central vacuoles. Choices: - alleles - tubules - nuclei - vacuoles A:
vacuoles
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Q: An individual with the appropriate number of what for their species is called euploid; abnormalities in this number include trisomy and monosomy? Read this paragraph and choose the correct option from the provided answers: Aneuploidy An individual with the appropriate number of chromosomes for their species is called euploid; in humans, euploidy corresponds to 22 pairs of autosomes and one pair of sex chromosomes. An individual with an error in chromosome number is described as aneuploid, a term that includes monosomy (loss of one chromosome) or trisomy (gain of an extraneous chromosome). Monosomic human zygotes missing any one copy of an autosome invariably fail to develop to birth because they lack essential genes. This underscores the importance of "gene dosage" in humans. Most autosomal trisomies also fail to develop to birth; however, duplications of some of the smaller chromosomes (13, 15, 18, 21, or 22) can result in offspring that survive for several weeks to many years. Trisomic individuals suffer from a different type of genetic imbalance: an excess in gene dose. Individuals with an extra chromosome may synthesize an abundance of the gene products encoded by that chromosome. This extra dose (150 percent) of specific genes can lead to a number of functional challenges and often precludes development. The most common trisomy among viable births is that of chromosome 21, which corresponds to Down Syndrome. Individuals with this inherited disorder are characterized by short stature and stunted digits, facial distinctions that include a broad skull and large tongue, and significant developmental delays. The incidence of Down syndrome is correlated with maternal age; older women are more likely to become pregnant with fetuses carrying the trisomy 21 genotype (Figure 13.7). Choices: - ribosomes - neutrons - genes - chromosomes A:
chromosomes
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Q: In plants and algae, photosynthesis takes place in which organelles? Read this paragraph and choose the correct option from the provided answers: In plants and algae, photosynthesis takes place in organelles called chloroplasts. Chloroplasts contain stacks of membranes called thylakoids, which contain chlorophyll. Thylakoids are surrounded by a fluid-filled space called stroma. Choices: - stems - fibroblasts - cells - chloroplasts A:
chloroplasts
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