5. A small peptide was found to contain equimolar amounts of the following amino acids: arginine, glutamic acid, glycine, lysine, methionine and phenylalanine. Individual samples of the peptide were treated with the following agents with the results noted: Reagent Specificity Trypsin Lys, Arg (C) Chymotrypsin Phe, Trp, Tyr (C) Staphylococcus V8 protease Glu, Asp (C) Pepsin Phe, Trp, Tyr (N) Cyanogen bromide Met (C) a) trypsin: arginine and a pentapeptide b) cyanogen bromide: two tripeptides c) S. aureus V8 protease: lysine and a pentapeptide d) chymotrypsin: a dipeptide and a tetrapeptide, with the latter showing absorbance at 280nm. What is the primary structure of the peptide

Read this summary of a scientific theory: "cells are the most basic structural and functional units of life. all living organisms are made up of one or more cells. all cells that are alive in the world today came from pre-existing cells." which of the following would require this theory to be modified? -a.) a survey finds that a majority of people believe viruses carry out the basic processes of life. -b.) a prominent scientist says she feels strongly that one day the theory will be challenged by life on other planets. -c.) the dna of unicellular and multi-cellular organisms is shown to have many fundamental similarities. -d.) scientific observations show that microscopic organisms living in the deep ocean are not made up of cells.

Which of the following is a feature of all cells? o a. all cells have a nucleus. o b. all cells have dna for at least part of their life cycle. het . o c. all cells are spheres. o d. all cells have a rigid cell wall.

Crinoids, also known as sea lilies, appear to be sea plants but are not plants at all. crinoids are an echinoderm species which uses anchoring structures called holdfasts to attach themselves to the sea floor. crinoids were most abundant in pennsylvania during the mississippian period, which ranged from 375 to 320 million years ago. fossils of the crinoids shows that during most of this time pennsylvania was that provided favorable conditions for crinoid growth. a) glacial terrain b) a dry and sandy plain c) mostly mountain ranges d) covered by warm, shallow seas