What phase of the cell cycle does DNA replication occur? a
G1
b
S
c
G2
d
M
e
cytokinesis

Simulating adaptations in a species in this activity, you will discuss in detail the adaptations in a species of rain forest plants. you will build a simulation that explains the changes in the traits of the plant population over 10 years. you will also establish a scientific explanation to justify the changes in the traits of the population, * time to complete: 1-2 hours part a an organism's adaptations are specific to its native environment. an organism that lives in a coniferous forest will have different adaptations compared to an animal that lives in a tropical rain forest. the following graphs show the temperature and precipitation throughout the year for two different forests: a coniferous forest in canada, and a tropical rain forest in belize. evaluate the graphs, and then explain why plants from these two ecosystems will have different adaptations. in your answer, explain the survival challenges that plants face in these two environments.

Mouse liver cells were homogenized and the homogenate subjected to equilibrium density-gradient centrifugation with sucrose gradients. fractions obtained from these gradients were assayed for marker molecules (i.e., molecules that are limited to specific organelles). the results of these assays are shown in the figure. the marker molecules have the following functions: cytochrome oxidase is an enzyme involved in the process by which atp is formed in the complete aerobic degradation of glucose or fatty acids; ribosomal rna forms part of the protein-synthesizing ribosomes; catalase catalyzes decomposition of hydrogen peroxide; acid phosphatase hydrolysis monophosphoric esters at acid ph; cytidylyltransferase is involved in phospholipid biosynthesis; and amino acid permease aids in transport of amino acids across membranes. a) name the marker molecule and give the number of the fraction that is most enriched for each of the following cell components: lysosomes; peroxisomes; mitochondria; plasma membrane; rough endoplasmic reticulum; smooth endoplasmic reticulum.

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?