Bio 205 Exam 1 Exam Questions With Complete Answers.

basic units of life that compose all living things - Answer-Cells characteristics shared by all cells - Answer--Cells are composed of 4 major macromolecules -Genetic material is carried and stored in the form of DNA -DNA is transcribed into RNA and RNA is translated into proteins -Their appearance, behavior, and function is dictated by proteins -They reproduce on their own -Respond to stimuli -Adapt to their environment -Are highly organized -Maintain a constant internal environment How are prokaryotes similar to chloroplast and mitochondria? - Answer--Contain their own DNA -Reproduce on their own How might an early anaerobic eukaryote have benefited from taking up a bacterium? - Answer-Use oxygen to produce energy Use sunlight to produce food molecules How did the engulfed bacteria/mitochondria benefit from being taken up by an early anaerobic eukaryote? - Answer-Engulfed bacteria live in the safe environment of the early eukaryotic cell Largest (9) to Smallest (1) _____ adenine _____ x-chromosome _____ Phage_____ tRNA _____ sperm _____ coffee bean _____ sesame seed _____ mitochondria _____ E.coli bacterium - Answer-9- coffee bean 8- sesame seed 7- sperm 6- X chromosome 5- mitochondria 4- E. coli 3- phage 2- tRNA 1- adenine Cell ___________ fits ____________. - Answer-structure, function Four methods to lysing cells - Answer--High frequency sound lyses cells -Mechanical force shears cells -Detergent lyses cells by puts holes in the plasma membrane -Cells forced through a small hole using high pressure break open What is the term used to describe the thick soup of cell extract produced when cell are broken open? - Answer-homogenate What is the technique that separates a homogenate into different parts? - Answer-centrifugation _____________________: repeated centrifugation at different speeds separates cell components based on size and density - Answer-Differential centrifugation___________: a matrix of small beads that separates proteins according to charge, size, hydrophobicity, or ability to bind to a specific molecule. - Answer-Chromatography What binds to column? What releases bound molecules from column? Ion Exchange chromatography - Answer--Molecules with a charge opposite of that of the beads in the column -Solvent that alters the pH of the column What binds to column? What releases bound molecules from column? Affinity chromatography - Answer--Proteins that interact with substrate molecule on the beads -Solvent that alters the pH of the column What binds to column? What releases bound molecules from column? Gel filtration chromatography - Answer--Small molecules that enter holes in the beads -Solvent that washed molecules ____________: identifies the presence of two or more fluorescent labels in the same place in a cell, tissue, or organelle - Answer-Co-localization______________: uses antibodies conjugated to a fluorophore that recognize a protein that is abundant in and localized to neurons! - Answer-expressing a transgene __________________: used to see if one protein interacts with another - Answer-BiFC What question does co-localization address? - Answer-Where in the cell is my protein located Note: two proteins can be in the same place and not interact. Co-localization does NOT test proteinprotein interactions. What question does BiFC address? - Answer-Does protein A interact with protein B ____________: widely employed analytical technique used to detect proteins in a sample of homogenate or cell extract. - Answer-Western blot 3 stages of a Western Blot - Answer-1) SDS-PAGE (SDS polyacrylamide-gel electrophoresis) 2) Transfer proteins onto a membrane (such as nitrocellulose) 3) Detection of proteins from the membrane using immunostaining _______ give amino acids their unique properties - Answer-Side chains Lysozyme -Where is it found? -What does it do? -How does it work? - Answer--Saliva, tears, human milk, mucus, other secretions -Catalyze hydrolysis of sugars in the bacterial cell wall.-Adds a water molecule to a single bond that joins two adjacent sugar groups in a polysaccharide chain causing the bond to break. Antibodies are globular proteins composed of 4 polypeptide chains, two of which are held together by a disulfide bond. What would be used to describe the structure of an antibody - Answer-quaternary structure Consider the description below and select the one that could be classified as a "protein domain." a) an α helix b) a complex of several polypeptide chains c) a substrate-binding pocket - Answer-C