The first forms of life to appear on earth were probably A. complex single- celled organisms

B. complex multicellular organisms

C. simple single-celled organisms

D. simple multicellular organisms

Which type of respiration takes place when there is no oxygen present

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.

Explain what a zygote is. use the terms egg cell, sperm cell, and fertilization in your explanation.