Essential nutrients move through a cell membrane by both passive transport and active transport. Which of the following correctly describes the transport of materials across a cell membrane? a) Active transport requires chemical energy to move nutrients from areas of low concentration to areas of high concentration.
b) Passive transport requires chemical energy to move nutrients from areas of low concentration to areas of high concentration.
c) Active transport moves nutrients from areas of high concentration to areas of low concentration without the use of chemical energy.
d) Passive transport moves nutrients from areas of low concentration to areas of high concentration without the use of chemical energy.

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.

Based on anatomical similarities, to which modern animal is dr. digger’s creature most closely related?

Where does all the water go? according to the environmental protection agency (epa), in a typical wetland environment, 39% of the water is outflow; 46% is seepage; 7% evaporates; and 8% remains as water volume in the ecosystem (reference: united states environmental protection agency case studies report 832-r-93-005). chloride compounds as residuals from residential areas are a problem for wetlands. suppose that in a particular wetland environment the following concentrations (mg/l) of chloride compounds were found: outflow, 60.4; seepage, 73.7; remaining due to evaporation, 26.4; in the water volume, 46.8. (a) compute the weighted average of chlorine compound concentration (mg/l) for this ecological system. (round your answer to one decimal place.) mg/l (b) suppose the epa has established an average chlorine compound concentration target of no more than 58 mg/l. does this wetlands system meet the target standard for chlorine compound concentration? yes. the average chlorine compound concentration (mg/l) is too high. yes. the average chlorine compound concentration (mg/l) is lower than the target. no. the average chlorine compound concentration (mg/l) is lower than the target. no. the average chlorine compound concentration (mg/l) is too high.