Ch.3

Question 1

what are the basic structures of a neuron

Answer 1

cell body (soma), dendrites (collect info from other cells), axon (carries messages to neurons)

Question 2

what is a dendritic spine?

Answer 2

protrusion from a dendrite that increases its surface area and is typical point of contact for other cells

Question 3

axon hillock

Answer 3

juncture of soma and axon where action potential begins

Question 4

axon collaterals

Answer 4

branches of an axon

Question 5

telodendrion

Answer 5

end branches of an axon

Question 6

terminal button

Answer 6

knob at tip of axon that conveys info to other neurons (also called end foot)

Question 7

synapse

Answer 7

gap between neurons

Question 8

what are the three types of neurons

Answer 8

sensory, motor, and interneurons

Question 9

sensory neurons

Answer 9

carry info from sensory receptors in or on the body to the spinal chord

Question 10

motor neurons

Answer 10

send signals from the brain and spinal cord to muscles

Question 11

interneurons (association neurons)

Answer 11

associate sensory and motor activity within the central nervous system

Question 12

what do bipolar neurons do?

Answer 12

transmit afferent sensory info from retinas light receptors to neurons that carry info to brains visual centers

Question 13

what is the purpose of somatosensory dendrite and how does it do this?

Answer 13

connects directly to its axon so the cell body sits to one side of this long pathway

Question 14

what are the 3 interneurons

Answer 14

stellate, pyramidal cell, purkinje cell

Question 15

stellate cell

Answer 15

star shapes, small with many dendrites that extend around cell body

Question 16

pyramidal cell

Answer 16

has long axon, a pyramid-shaped cell body, two sets of dendrites apical and basal

Question 17

purkinje cell

Answer 17

a distinctive interneuron with extremely branched dendrites that form a fan shape

Question 18

where do motor neurons reside

Answer 18

in the lower brainstem and the spinal cord

Question 19

what are the three organizational aspects of neurons

Answer 19

input, association, and output

Question 20

(glial cell) ependymal cell

Answer 20

small ovoid, found in walls of ventricles, make and secretes cerebrospinal fluid

Question 21

(glial cell) astrocyte

Answer 21

star shaped, gives neurons structural support, transport substances between blood-brain barrier, forms scar tissue, fuels active brain areas

Question 22

microglial cell (glial cell)

Answer 22

small, derived from blood, defensive function to remove dead tissue (phagocytosis)

Question 23

(glial cell) oligodendroglial cell

Answer 23

forms myelin around CNS axons in brain and spinal chord

Question 24

(glial cell) schwann cell

Answer 24

wraps around peripheral nerves to form myelin in axons

Question 25

myelin

Answer 25

glial coating tha surrounds axons

Question 26

multiple sclerosis (MS)

Answer 26

nervous system disorder associated with loss of myelin

Question 27

how are neurons repaired

Answer 27

schwann cells shrink then divide to form glial cells along axons former path, neuron sends out axon sprouts and finds schwann cell path to become new axon

Question 28

what determines a cells characteristics and functions?

Answer 28

a cells proteins, water, salts, and ions as well

Question 29

what does the cell membrane do?

Answer 29

separates intracellular and extracellular fluid, regulates movement of things in and out of cell, and is mad up of phospholipids

Question 30

chromosome

Answer 30

2x stranded molecule of DNA

Question 31

ribosomes

Answer 31

protein structures that act as catalysts for protein synthesis

Question 32

translation

Answer 32

where messanger RNA travels from nucleus to ER where mRNA is translated into amino acid sequences to form protien

Question 33

transcription

Answer 33

DNA strands unwind and a complimentary strand of mRNA is produced

Question 34

what does an amino acid consist of?

Answer 34

central carbon atom bound to hydrogen atom, amino group, carboxyl group and a side chain linked together by peptide bond

Question 35

golgi bodies

Answer 35

package proteins in vesicles (membranes) and give them a label as to where they should go

Question 36

microtubules

Answer 36

transport the vesicles to their destinations inside or outside of the cell

Question 37

tay-sachs disease

Answer 37

inherited at birth, caused by loss of genes that encode the enzyme that breaks down fatty substances, results in intellectual disability, physical changes and death by 5yrs

Question 38

huntington disease

Answer 38

causes by increase in number of CAG on chromosome 4 autosomal disorder, cognitive+motor disturbances

Question 39

what do genetic disorders result from

Answer 39

aberration of a chromosome --> not a single defective allele

Question 40

down syndrome

Answer 40

intellectual impairment and other abnormalities, occurs w/ extra copy of 21st chromosome (trisomy)

Question 40

what are approaches to genetic engineering?

Answer 40

selective breeding, cloning, transgenic techniques, knockouts

Question 41

selective breeding

Answer 41

alters gene expression, objective is to maintain spontaneous mutations

Question 42

cloning

Answer 42

where you produce an offspring that is genetically identical to another, can be used to observe heredity and impact of environment

Question 43

what is transgenic technique

Answer 43

introduction or removal of genes into embryo with knock in technology to inactivate gene

Question 44

phenotypic plasticity

Answer 44

capacity of genome to express many phenotypes

Question 45

epigenetics

Answer 45

the influence of environment on selection of one or another phenotype

Question 46

what does the absence of a corpus callosum result from?

Answer 46

an epigenetic influence on whether trait is expressed in a particular mouse

Question 47

what is observed in patterns of disease in identical twins?

Answer 47

lack of concordance (incidence of similar behavioral traits)

Question 48

what can be viewed as a second genetic code?

Answer 48

epigenetics

Question 49

what do epigenetic mechanisms influence

Answer 49

protein production by blocking or unblocking a gene so that it can or cant be transcribed

Question 50

how can environment influence induce or remove one or more blocks of genes to regulate gene expression?

Answer 50

histone modification: DNA unwraps or stopped from unwrapping in histone DNA methylation: transcription of DNA into mRNA enabled or blocked mRNA modification: mRNA translation may be enabled or blocked