Punnet and his colleagues mated a purebred purple flower, long pollen sweet pea with a pure-bred red flower, round pollen sweet pea and obtained an F1 with purple flower and long pollen. What mating should they do to determine the recombination frequency between the gene that controls the color of the flower and the gene that controls the shape of the pollen?

What are some things that limit population growth?

Which image shows labeled organelles that are present only in plant cells?

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.