Lloyd’s lab partner is looking down into a test tube while he heats the contents by using a flame. which action should lloyd recommend to his partner if heating must continue?
a. wear safety goggles while looking into the opening of the test tube.
b. cover the opening of the test tube so that no materials can boil out of it.
c. move the test tube so that the opening is pointing away from all students.
d. put the test tube in a hot water bath so that no water can enter its opening.

Which type of bacterial reproduction is depicted in the diagram?

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 feature of a human community is similar to a niche in a biological community