cell and molec exam 1

What approaches can we use to study cells

cytocology, genetics, biochemistry

how can we visualize cells

cells are visualized by microscopy

what does light microscopy use

visible light

what does light microscopy reveal

cell shape and size, tissue organization, some cellular structures, living cells

what are the advantages of light microscopy

simple, live cell imaging

what are the limitations of light microscopy

limited resolution

fluorescence microscopy uses what

fluorescent labels

what does fluorescent microscopy reveal

specific proteins, cellular structures, molecular localization

what are the advantages of of fluorescent microscopy

high specificity, multiple targets

what are the limitations of fluorescent microscopy

requires labeling, resolution is limited by light wavelength

what is specialized fluorescence microscopy called

confocal microscopy

what does a confocal microscope do

optical sectioning removes out of focus light and turns z stacks to 3d images

what are the advantages of a confocal microscope

Sharp, 3D images

what are the limitations of a confocal microscope

specialized equipement; fluorescent labels

what are the two types of electron microscopes

Transmission electron microscopy, scanning electron microscopy

what does electron microscopy use

electron beam

what are the advantages of electron microscopy

Very high resolution

What does a TEM show

internal structures, organelles and membranes

What does SEM show

cell surfaces, 3D like images

What are the limitations of electro microscopy

fixed, processed specimens

What are shared features of all cells

plasma membrane, cytoplasm, DNA, Ribosomes, cell membranes, genetic material, energy metabolism, enzymes/proteins

What distinguishes eukaryotic and prokaryotic cells

eukaryotic cells contain a nucleus and membrane bound organelles while prokaryotic cells contain neither

What are distinguishing features of eukaryotes

membrane bound organelles, 80S ribosomes, mitochondria

What are distinguishing features of prokaryotes

nucleoid, 70S ribosomes

What are the macromolecules in prokaryotic cell component: ribosomes

RNA, Proteins

What are the macromolecules in prokaryotic cell component: Chromosomal material

DNA,Proteins, RNA

What are the macromolecules in prokaryotic cell component:Cytoplasm

RNA,Proteins,Lipids,Polysaccharides

What are the macromolecules in prokaryotic cell component: cell membrane

Proteins, Lipids

What are the macromolecules in prokaryotic cell component: Cell Wall

Polysaccharides, Proteins

What are the macromolecules in prokaryotic cell component: Capsule

Polysaccharides

What are the macromolecules in Eukaryotic Cell cell component: Smooth ER

Proteins and lipids

What are the macromolecules in Eukaryotic Cell cell component: Plasma membrane

proteins and lipids

What are the macromolecules in Eukaryotic Cell cell component: lysosome

proteins, lipids, polysaccharides

What are the macromolecules in Eukaryotic Cell cell component: microtubule

proteins

What are the macromolecules in Eukaryotic Cell cell component: ribosomes

RNA, proteins

What are the macromolecules in Eukaryotic Cell cell component: centrioles

proteins

What are the macromolecules in Eukaryotic Cell cell component: cytoplasm

ribosomes, proteins, lipids, polysaccharides

What are the macromolecules in Eukaryotic Cell cell component: mitochondria

DNA, RNA, Proteins, Lipids, Polysaccharides

What are the macromolecules in Eukaryotic Cell cell component: flagellulm

Proteins

What are the macromolecules in Eukaryotic Cell cell component: peroxisome

proteins and lipids

What are the macromolecules in Eukaryotic Cell cell component: nucleolus

RNA and Proteins

What are the macromolecules in Eukaryotic Cell cell component: Nucleus

DNA, RNA, Proteins

What are the macromolecules in Eukaryotic Cell cell component: chromatin

DNA, Proteins, RNA

What are the macromolecules in Eukaryotic Cell cell component: microvilli

Proteins and lipids

What are the macromolecules in Eukaryotic Cell cell component: Rough ER

RNA, Proteins, and Lipids

What are the macromolecules in Eukaryotic Cell cell component: Microfilaments

Proteins

Golgi apparatus

Proteins, Lipids, Polysaccharides

What is the difference between an alpha linkage and a beta linkage

is the orientation of the bond between glucose molecules: an alpha linkage connects in one direction a beta linkage connects in the other

What causes a polysaccharide to have a 3D structure

the different orientation between alpha and beta linkages

What amino acid most closely resembles phosphorolyated serine

aspartic acid

4. DNA oligos are written 5′ → 3′ What do the “3” and “5” refer to?

• 5′ carbon → associated with the phosphate group

• 3′ carbon → has the hydroxyl (–OH) group used to form the next phosphodiester bond

Why does this justify writing DNA sequences 5′ → 3′?

Nucleotides are assembled by forming phosphodiester bonds between the 3’-OH of one nucleotide and the 5’phosphate of the next nucleotide. therefore, DNA has directionality and is read in 5-3