WITH ACCURATE ANSWERS
Assuming only water can diffuse across a cell membrane, draw a picture of an
animal cell in an 1) isotonic solutions 2) hypertonic solution 3) hypotonic solution.
correct answer isotonic solutions- condition in which the solute concentrations on
both sides of a plasma membrane are equal, which does not cause a cell to shrink
or swell
hypertonic solutions- any solution that causes a cell to shrink due to osmosis of
water out of the cell
hypotonic solutions- any solution that causes a cell to swell when placed in that
solution
Beginning with the cornea and ending with the optic never, name and give the
function of each part of they eye involved in photoreceptor in humans. (Figure
43.14, 43.21). correct answer Sclera - strong outer white sheath
Cornea - continuous with sclera but thin and clear
2 cavities - anterior holds aqueous humor, posterior holds thick vitreous humor
(maintains eye shape)
Iris - pigmented smooth muscle controlling size of pupil
Look at the pic for the rest
Cornea and lens bend incoming light
Lens is adjusted by ciliary muscles to focus light (accommodation)
Beginning with the pinna and ending with the auditory nerve, name and give the
function of each part of the ear involved in audition in humans (Figure 43.5, 43.6,
43.7). correct answer Sound waves enter the outer ear in the pinna which
captures sound waves
Tympanic membrane (eardrum) vibrates back and forth
,Ossicles transfer vibration to oval window
Sends pressure waves through cochlea (collect sound)
Waves travel from auditory canal to tympanic canal and dissipate against round
window
Waves pass under basilar membrane moving it up and down
Mechanical forces transduced into electrical signals by organ of Corti
Up-and-down vibration of basilar membrane move hair cells
Stereocilia bending causes action potentials in auditory nerve
Compare and contrast the 2 kinds of ER. correct answer rough-studded with
ribosome; sorts proteins that are destined for ER, Golgi, lysosomes, vacuoles,
plasma membrane, or outside the cell; proteins are packaged into membrane
vesicles and moved from one location in endomembrane system to another;
insertion of certain newly made proteins into the ER membrane; attachment or
carbs to proteins and lipids (glycosylation)
smooth-lacks ribosomes; functions in diverse metabolic processes; provides an
increased surface area for enzymes that play important metabolic roles; detoxify
many potentially harmful organic molecules (liver); carbohydrate metabolism,
store energy in the form of glycogen (polymer of glucose); accumulation of
calcium ions, contains Ca pumps; critical in synthesis and modification of lipids;
enzymes in smooth ER are necessary for certain modifications of lipids cholesterol
that are needed to produce steroid hormones (estrogen and testosterone)
Comport and contrast DNA and RNA. correct answer DNA-sugar is deoxyribose,
thymine instead of uracil, 2 strands=double helix, one form
RNA-sugar is ribose, uracil instead of thymine, single strand (usually), many forms
(mRNA, tRNA, rRNA)
both-pentose sugars; adenine, guanine, cytosine
, Define diploid and haploid. Name the types of cells in humans that are diploid and
haploid. correct answer diploid-containing two complete sets of chromosomes,
one from each parent (in humans all cells except sex cells are diploid)
haploid-having a single set of unpaired chromosomes (in humans sex cells are
haploid)
Define glia and give functions of the types. correct answer These are cells that
surround the neurons and perform numerous supporting roles. Types include:
-oligodendrocytes (CNS)/ Schwann cells (PNS), which make up the myelin sheath
that surround the axons of neurons
-astrocytes (they look like stars, hence "astro"), which provide metabolic support
and are involved in forming the blood-brain barrier
-Microglia, which remove cellular debris produced by damaged or dying cells
-Radial glia, which form tracks for neuronal migration in embryos
Astrocytes and radial glia also function as stem cells to produce more glia and
neurons
Define learning and memory. Describe how memory was studied in sea slugs.
correct answer learning-process by which new information is acquired
memory-involves retention of that information over time
Define membrane potential. Describe the 3 factors that contribute to it. correct
answer -Difference in charge between the inside (more negative) and outside
(more positive) of the neuron, making it electrically polarized
-The plasma membrane barrier separates the charges