While hiking last year, Mike saw a large boulder next to a mountain trail. The boulder had no cracks. While hiking on the trail this year, he saw two large cracks in the boulder. Which of the following most likely caused these cracks to form?
Shaking from high winds.
Pressure from flowing water.
Erosion due to falling rain and snow.
Weathering due to freezing and thawing

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.

What best explains the inability for life to exist in earth early atmosphere

Anne, an intern in a microbiology lab, was observing the characteristics of various specimens of protists. match each specimen to the category of protist to which it belongs.