Think of the human brain for a moment. It is an incredibly complex mechanism. It consists of a range of structures, including hemispheres, lobes, and even layers. Each structure is comprised of various types of cells, including nerve cells, blood cells, and cells that make up blood vessels. Where do you think all these cells came from? Consider what you know about mitosis and meiosis. Have the cells that make up your brain existed since fertilization? If so, how does human growth occur? If not, can you trace their origins back to fertilization?

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.

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )

What is one way intensive agriculture can contribute to climate change? a. tree loss to agriculture increases earth's albedo b. livestock manure absorbs greenhouse gases c. large herds of livestock release greenhouse gases d. fewer trees are available to replenish petroleum stores appex