Carrier-mediated transport is necessary when
A) diffusion will not allow adequate amounts of a substance to enter the cell.
B) movement into the cell is against a concentration gradient.
C) the level of nutrients in nature is very low.
D) nutrient concentration is very low in the environment, is higher inside of the cell, or diffusion is not possible.
Answer: D
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Answer the following statement true (T) or false (F)
Answer the following statements true (T) or false (F)
1. A consequence of the tendency of the human to gain excess weight is an increased risk of developing high blood pressure, diabetes, cancer, and heart disease. 2. During hibernation, a bear would be expected to be in the postabsorptive state in terms of nutrient utilization. 3. Triglycerides do not need to be chemically altered or broken down to cross the intestinal epithelium. 4. Animals have the ability to generate glucose from proteins during prolonged postabsorptive states.
his4 TRP1; his4 trp1; HIS4 trp1; HIS4 TRP1
A haploid yeast strain has mating type a and genotype his4 TRP1. A different haploid yeast strain has mating type ? and genotype HIS4 trp1. The two strains mate and produce diploid offspring with genotype his4 TRP1 / HIS4 trp1. The diploid cells undergo meiosis to produce a variety of tetrad types. In the following questions, the genotypes of the spores in a tetrad are shown. For each tetrad, tell what type it is: parental (PD), non-parental (NPD), or tetratype (T). A) PD B) NPD C) T D) cannot be determined
All of the following are reproductive isolating mechanisms except:
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