Mitosis is the division of the and begins with a stage called . As the nuclear envelope finishes dissolving, the cells enter , where microtubules from the spindle attach to the duplicated X-shaped chromosomes. When all chromosomes are fully attached to the spindle, they align at the midplate between poles. This marks the middle of mitosis, which is . As sister chromatids separate, cells enter and they finish separating and a nucleus reforms around each set of new chromosomes in . During this phase, cytokinesis also becomes visible as the cells themselves begin to divide.

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.

If the coding part of an mrna molecule is 1800 nucleotides (bases) in length, this molecule will contain codons and code for a polypeptide that is amino acids long.

Which two factors contributed to creating a global culture? the creation of the united nations improvement in telecommunications health issues such as the ebola virus increased opportunities for global travel