exam 1- 3 missed questions Flashcards
Structure of monosaccharide
Carbon ring with OH groups (basically look for the carbon chain)
A dehydration reaction is a process in which
Monomers are joined together to form a polymer, which is a build up of molecules that results in the production of water in the process
What is the Homeoviscous Adaptation Hypothesis
a process that helps cell membranes maintain a liquid-crystalline state in cold temperatures. (which would have the greatest amounts of unsaturated phospholipids.)
What structure of a protein determines its function and shape
Primary structure
A mutation causes a new amino acid to be substituted into a protein. What level of protein structure will always be effected?
Primary
What amino acid substitutions will potentially have the most destabilizing effect on the protein secondary structure?
A polar amino acid changed to non polar
Describe the shape and structure of a primary protein
order of amino acids (so basically just the drawing)
Describe the shape and structure of a secondary protein
H bonds and interactions between nearby amino acids (so in this case think the yellow and dark blue) - examples include beta sheets or alpha helices
Describe the shape and structure of a tertiary protein
R groups of far away amino acids interacting (like pink and light blue) for more extensive folding
Describe the shape and structure of a quaternary protein
multiple polypeptides interacting (NOT ALL PROTEINS HAVE QUATERNARY STRUCTURES)
Describe direct intercellular signaling
cell junctions allow signaling molecules to pass from cell to cell
Describe Paracrine signaling
signal does not affect cell secreting the signal but does influence cells close to it
Describe contact-dependent signaling
Molecules are bound to the surface of cells and serve as signals to cell coming in contact with them
Describe endocrine signaling
Signals (hormones) travel long distances and are usually longer lasting
Describe autocrine signaling
Cells secrete signaling molecules that bind to their own cell surface or neighboring cells of the same type
Summarize the 4 signal transduction pathways we discussed in class: g-coupled protein
Signaling molecule binds to GPCR, receptor binds to inactive G protein, activates it, it leaves the receptor and activates downstream enzymes
receptor tyrosine kinases
The domain binds to a ligand which causes two domains to come together and form a dimer, tyrosine amino acids are phosphorylated, by kinases, proteins bond to the side groups and perform cellular responses
intracellular receptors
A hormone (typically a steroid) enters the cell and binds to the hormone-receptor protein complex. The complex interacts directly with DNA in the cell to affect gene expression
ligand-gated channels
A ligand binds to the gated channel which causes it to open and allow ions to flow through. Once ions enter the cell the ligand separates from the channel and the channel closes
How does auxin affect plants
phototropism (cell elongation)
How does cytokinins affect plants
cell division
How does abscisic acid affect plants
leaf abscission and winter dormancy
How does gibberellins affect plants
fruit growth
How does ethylene effect plants
Fruit ripening, only gaseous hormone
Describe characteristics and uses of parenchyma
thin primary cell walls, no secondary walls, they store organic products, hold chloroplasts, are the fleshy parts of fruits, and make up the sieve-tube members of the phloem, have totipotency.
Describe characteristics and uses of collenchyma
living specialized cells, unevenly thick primary walls, form strands to help support young plants, flexible
Describe characteristics and uses of Sclerenchyma
dead specialized cells, thick secondary walls with lignin, support the plant and help with transportation, make up xylem vessel elements.
what role does the Golgi play in protein production
Modifies proteins (post-office)
Where are microfilaments most likely to be found
Along the inner surfaces of the membrane
