Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Embryology > Fourth Exam > Flashcards

Fourth Exam Flashcards

1
Q

What are the 4 extraembryonic membranes

A

amnion
chorion
yolk sac
allantoic sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the functions of these extra embryonic membranes

A

protection
nutrition
respiration
excretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In birds, what occurs to the ectoderm and the somatic plate mesoderm

A

laminate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does this lamination produce

A

a single layer of membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the name of this membrane created by the lamination of the ectoderm and the somatic plate mesoderm

A

somatopleure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What occurs to the endoderm and the visceral plate mesoderm in birds

A

they laminate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the name of the layer that formed from the lamination of the endoderm and visceral plate mesoderm

A

splanchnopleure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the somatopleure do

A

lifts up to fuse on the dorsal side of the embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does the lifting and fusing of the somatopleure produce

A

two coverings for the embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two coverings produced called

A

chorion and amnion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the space between chorion and amnion membranes

A

extra embryonic ceolom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the name of the cavity between the amnion and the epidermis

A

amniotic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the amniotic cavity serve as in birds

A

a shock absorber
heat capacity
avoids dehydration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the splanchnopleure do

A

moves downwards to surround the yolk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does surrounding the yolk sac with the splanchnopleure produce

A

the yolk sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does the yolk sac retain connection to the embryo

A

via the gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What occurs to the splanchnopleure other than surrounding the yolk sac

A

an evagination occurs of the hindgut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does the evagination of the hindgut form

A

the allantoic sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What occurs to the allantoic sac

A

grows, pushes into the extraembryonic coelom to surround the entire embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Do mammals have the same membranes as birds

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the difference of the membranes of mammals rather than birds

A

they have different origins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where does the amnion come from in mammals

A

amniotic ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the final product of the amnion

A

it surrounds the entire embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What creates the somatopleure in mammals

A

amniotic ectoderm and extra embryonic mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why is it important for the allantoic sac to surround the bird

A

allows for gas exchange to occur since it doesn’t have a placenta, allows for collection of metabolic wastes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What metabolic waste collects in the allantoic sac

A

uric acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the three initial layers of cells in mammals

A

amniotic, epiblast, hypoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Where do extra embryonic mesoderm come from

A

nothing holds some mesoderm cells as the three primary germ layers are being created

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Where do the extra embryonic mesoderm cells travel

A

around to the top of the amniotic ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does the amniotic ectoderm and extra embryonic mesoderm create

A

somatopleure layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What occurs to the amniotic cavity

A

it surrounds the embryo to bath it in fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where does amniotic fluid come from initially

A

most diffuses from the endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Where does amniotic fluid come from once the embryo’s circulatory system is set up

A

it oozes out through the non-karotinized skin cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Where does amniotic fluid come from later in develop

A

baby’s mucous membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What mucous membranes contribute to amniotic fluid

A

respiratory, digestive, urinary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the importance of amniotic fluid

A

allows symmetrical external growth of the embryo
acts as a barrier to infection
permits fetal internal organ development
cushions the embryo
prevents adherence of amnion to the embryo
maintains constant temperature
allows fetal movement, promotes muscle development
assists in maintaining fluid and electrolytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How does amniotic fluid permit fetal internal organ development

A

lungs inhale
digestive system swallow
urinary system filters it
organs practice on the amniotic fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the disease where one does not have enough amniotic fluid

A

olgohydramnios

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What does olgohydramnios cause symptom wise in babies

A

alters facial development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How does the amnion maintain fluid and electrolytes

A

amnion is a filter between maternal and baby blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How often is the amniotic fluid changed

A

every 3 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Is amniotic stationary

A

no, it is always moving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Near the end of pregnancy, how much amniotic fluid is present

A

700-1000ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How does the artificial womb work

A

takes over the circulation system of an embryo, pumps fluid through amniotic cavity to keep moving the amniotic fluid, connects umbilical circulation with o2 and CO2 lines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Where does the chorion come from in human embryos

A

cytotrophoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Where does the cytotrophoblast come from

A

naturally surrounds the embryo, from the endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

The endometrium is made up of what two layers

A

cytotrophoblast and syncytiotrophoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What occurs to the cytotrophoblast layer to create the chorion

A

sends out fingers through the synctiotrophoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are these fingers called

A

chorionic villi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What do the villi do for function

A

reach into pools of maternal blood in the endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Where do umbilical vesicles develop from

A

extra embryonic mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Where do the umbilical vesicles form

A

inside of the connecting stalk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What does the connecting stalk do

A

connect the embryonic circulatory system with the chorionic villi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

In the embryonic circulatory system, how are nutrients obtained, through which route

A

umbilical vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

In the embryonic circulator system how are wastes disposed of into maternal blood

A

umbilical arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What happens to the cavity between the chorion and amnion

A

it disappears as the embryo grows

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

As the embryo grows, what occurs

A

it bulges out of the endometrium into the uterine cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

As the embryo bulges into the uterine cavity, it remains in contact with what

A

the chorionic villi and endometrium on one side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What does the contact with the chorionic villi and endometrium on one side form

A

placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What do many people think the yolk sac is

A

a junk sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

In mammals what is the yolk sac known as

A

umbilical vesicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What are functions of the umbilical vesicle

A

transfers nutrients
blood initially develops here
contributes to buds and branches of gut
primordial germ cells originate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What eventually occurs to the umbilical vesicle in mammals

A

it shrivels up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Where do the nutrients come from that the umbilical vesicle transfers

A

endometrium into the embryo’s gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

How is blood initially developed by the umbilical vesicle

A

EE mesoderm on the outside of the umbilical vesicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What part of the umbilical vesicle contributes to the buds and branches of gut

A

endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

After the primordial germ cells are made in the umbilical vesicle, what occurs

A

they move up to the mesonephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Where does the allantoic sac come from in mammals

A

evagination of the hindgut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Does the allantoic sac in mammals expand as it does in mammals

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Why does the allantoic sac in mammals not expand

A

respiratory and excretory functions are performed by the placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

How is the umbilical cord created

A

ventral closure squeezes all EE membranes and umbilical vessels into the cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

In a cross section of the umbilical cord, what things can be seen

A 
ectoderm on edge
mesoderm  on inner
vein in middle
two arteries
allantoic stalk
leftover yolk of umbilical vesicle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

In regards to sex, how do all embryos start out

A

the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Most vertebrate species will develop to what kind of sex

A

look, act quite differently, sexually dimorphic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

In many invertebrate species what will develop in regards to sex

A

males and females are less obviously different, some are both male and female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What are organisms that are both male and female called

A

hemaphrodites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Why do organisms begin developing differently at some stage

A

the environment or its the

genes they inherent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

How does the environment contribute to sex determination

A

temperature, nutrient level, bacterial infection, population density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

In a dense population, what sex is not common

A

females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Why are there more males in a dense population

A

no need to reproduce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

How does temperature develop sex

A

alligators make one sex in cold water and the other in warm water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

How do genes influence sex determination

A

determining what genes you have determines sex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

In mammals what genes determine sex

A

XY male

XX female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

In birds, what determines sex

A

zz male
zw female
one has same gene the other has two different

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

For some animals what part of the gene determines sex

A

autosome, locus on a chromosome that if you are heterozygous you are male and homozygous is female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

insects that are haploid are what sex

A

male

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

insects that are diploid are what sex

A

female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

In mammals is it the X or the Y gene that leads to male

A

Y gene, two XX don’t make you a female automatically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What chromosomes do Klinefelter syndrome individuals have

A

XXY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What anatomical sex do individuals with Klinefelter syndrome have

A

sterile male

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

What chromosomes do Turners syndrome individuals have

A

XO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What anatomical sex do individuals with Turners syndrome have

A

sterile female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

In the beginning you develop as what

A

both genders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

At some point, what occurs

A

differentiation into final gender

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What is the default pathway for gender differentiation

A

female unless you have a Y chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

At the indifferent sex stage, what is present in the embryo

A

mesonephric duct
mesonephros
mullerian ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What forms from the mesonephric duct

A

the vas deferens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What forms from the mesonephros

A

gonads are occurring, indifferent gonads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

What do the mullerian ducts connect with

A

the cloaca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What do the mullerian ducts become

A

ovaducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

In males, what does the gonads become

A

testes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What occurs to the nephric duct in males

A

becomes vas deferens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

What occurs to the mullerian ducts in males

A

they disassemble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

If you inherit one Y chromosome, what do you become

A

male

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

If you lack a Y chromosome, what do you become

A

female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

In females, what happens to the mullerian ducts part way

A

they fuse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What does the Y chromosome contain

A

a gene called TDF or SRY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What is TDF

A

testis determining factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What is SRY

A

sex determining region of the Y chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

In females, what occurs to the nephric ducts

A

they disassemble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What do the gonads in females become

A

ovaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

If the mullerian ducts don’t completely fuse into one, what is caused

A

didephys uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

What is didephys uterus

A

split uterus with a wall between

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

The gonads are made from at least how many kinds of cells

A

two different

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

What two kinds of cells make up the gonads

A

intermediate mesoderm

germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

What region of the intermediate mesoderm contributes to gonads

A

mesonephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What does the intermediate mesoderm form for the gonad structure

A

body of the organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

The intermediate mesoderm is also the what of the organ

A

somatic cells or permanent framework

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

In opposition of the germ cells that become gametes and leave, what does the intermediate mesoderm do

A

never leave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

Where do the primordial germ cells come from

A

migrates from the umbilical vesicle via the gut tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

What do the germ cells form as part of the gonad

A

arrange themselves in rows and cords

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

What are these rows or cords called

A

primitive sex cords

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What other cells do the intermediate mesoderm create

A

supporting cells
steroidal cells
connective tissue cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What are the two steroidal cells/ gender

A

male=interstitial

female=granulosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

What are the two supporting cells/gender

A

sertoli=male

follicle cells=female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What do the connective tissue cells make up

A

scaffold of the organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

At the arrangement of the sex cords, has sex differentiation occurred

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

What causes the differentiation of the gonads

A

if the supporting cells have Y chromosomes or not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

If the supporting cells have Y chromosomes, what occurs

A

the supporting cells express the TDF gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

What does expressing TDF gene cause

A

neighboring cells to develop in certain ways that could have gone either way

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

What occurs to the primitive sex cords when TDF gene is expressed

A

the cords on the edges of the gonad disappear, leaving only those in the middle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

What do the sex cords in the middle of the gonad develop into

A

seminiferous tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

How do the cells on the edge of the gonad disappear

A

cell suicide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

What do the primordial germ cells become when TDF is expressed

A

spermatogonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

What do the steroidal cells produce when TDF is expressed

A

testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

What does testosterone do

A

influence many other cells near and far

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
137
Q

What do the supporting cells produce when TDF is expressed

A

anti-Mullerian duct hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
138
Q

What does the anti-Mullerian duct hormone do

A

kills mullerian duct cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
139
Q

Where do the testis initially form

A

abdominal cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
140
Q

What occurs to the testes shortly before birth

A

descend to their eventual location

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
141
Q

what occurs to the edges of the gonads when TDF is expressed

A

it gets a thick capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
142
Q

What is the thick capsule called

A

tunica albuginea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
143
Q

If there is a mutation for the anti-mullerian duct hormone or the receptor what occurs

A

genetic male, anatomic male with ova-ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
144
Q

If the supporting cells do not have a y chromosome what pathway is taken

A

the default pathway to become female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
145
Q

What occurs to the sex cords when no y chrom is present

A

the middle sex cords disappear, leaving only the ones on the edges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
146
Q

What is the edge of the gonad called

A

cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
147
Q

What is the middle of the gonad called

A

medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
148
Q

What do the sex cords on the edges of the gonads do

A

break up into primordial follicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
149
Q

What occurs to the primordial germ cells right away

A

they enter into meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
150
Q

What week of development do the germ cells enter meiosis

A

before the 12th week of development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
151
Q

What do the steroidal cells produce in females

A

estrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
152
Q

What occurs to the mullerian ducts

A

persist to become oviducts which merge at far end of the uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
153
Q

Where do the ovaries initially develop

A

abdominal cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
154
Q

What occurs in development to the ovaries in placement within the body

A

descend to the pelvic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
155
Q

How could an XY female persist

A

if TDF gene or the promotor is mutated, TF is mutated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
156
Q

At the most fundamental level, what three things determine sex

A

genetics
embryology
choice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
157
Q

How does genetics determine sex

A

testosterone vs estrogen genes. Combo of genes not just one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
158
Q

How does embryology determine sex

A

the way things develop if primordial germ cells don’t make it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
159
Q

How does choice determine sex

A

freedom/nature, worldview, person gets to decide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
160
Q

What is the ratio for the number of individuals that the anatomy does not match the genes

A

1/4500

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
161
Q

In males vs females, how could the sex chromosomes lead to differences in gene products

A

more products could be produced from X chromosome in females than in males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
162
Q

How many genes on X chromosomes

A

1606

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
163
Q

What could the extra doses of gene products of the X chromosome lead to

A

disease and or death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
164
Q

If the X chromosome had a growth factor, how could double of X products be a problem

A

twice the urge to have cells proliferate, 2x chance of cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
165
Q

How is this double dosage problem in females solved

A

inactivation of one of the chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
166
Q

When is the one chromosome entirely inactivated

A

in each cell of the epiblast layer, shortly after cell mass is formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
167
Q

How many cells are present when an X is inactivated

A

a few hundred cells at this stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
168
Q

Is this a random or scheduled inactivation process. Are the paternal or maternal ones inactivated?

A

some are paternal, some are maternal, random

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
169
Q

What causes the inactivation of an X chromosome

A

accumulation of the produce XIST

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
170
Q

Where is the XIST gene located

A

on a locus on the chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
171
Q

What occurs to produce XIST

A

gets transcribed into RNA, never gets translated, RNA attaches to rest of chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
172
Q

What occurs as the RNA coats the chromosome

A

it gets inactivated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
173
Q

How does the RNA coating the chromosome lead to inactivation

A

RNA attracts methylation enzymes that cause methyl groups to be put everywhere and inactivate it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
174
Q

What happens to the inactivated chromosome

A

it forms into a Barr body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
175
Q

When does the Barr body unfold

A

only for replication prior to mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
176
Q

What does the random inactivation lead to

A

chimerism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
177
Q

What is an example of X linked chimerism

A

calico cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
178
Q

What is the most obvious example of pattern formation in development

A

limb development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
179
Q

How is a pattern seen in limb development

A

humans have the similar structures in the same pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
180
Q

This pattern develops from what

A

the same embryonic structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
181
Q

What causes the patterns to develop

A 
cells dividing at different speed
cell aggregation
cell growth
programmed cell death
embryonic induction
expression of certain genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
182
Q

How does cells dividing at different speeds contribute to patterns

A

cells with faster speed make greater amount of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
183
Q

How does cell aggregation contribute to patterns

A

cells aggregate in certain areas and don’t in other areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
184
Q

How does cell growth contribute to patterns

A

elongation, esp, muscle cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
185
Q

How does programmed cell death lead to patterns

A

occurs at certain points to get rid of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
186
Q

How does embryonic induction lead to patterns

A

chemical morphogens lead to ends and gradients of chemicals, concentration is proportional to distance, cells respond differently to different concentrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
187
Q

How do genes contribute to patterns

A

specify regional differences in the anteroposterior body pattern during embryonic development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
188
Q

What are pattern forming genes

A

homeotic genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
189
Q

homeotic genes are expressed in what motion across the embryo

A

anterior to posterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
190
Q

When homeotic genes get mutated what occurs to the patterns

A

they get disrupted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
191
Q

If the wingless gene in flies gets mutated, what happens

A

flies don’t have wings and instead have more legs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
192
Q

Homeotic genes are how long

A

1000bp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
193
Q

of the 1000bp a certain region codes for what

A

consensous sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
194
Q

How long is the region that codes for the consensous sequence

A

180bp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
195
Q

What does the consensous region code for

A

homeobox

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
196
Q

What is the homeobox

A

HOX genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
197
Q

How are the HOX genes arranged on a chromosome

A

in order and clustered together to be expressed in bunches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
198
Q

the 180bp region codes for what

A

homeodomain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
199
Q

How big is the homeodomain

A

60 AA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
200
Q

What is the function of the homeodomain

A

bind to DNA, making the products of homeotic genes, transcription factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
201
Q

some of the HOX genes are what kind of genes

A

master control genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
202
Q

What are the three axis of limb development

A

proximal-distal
dorsal-ventral
anterior-posterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
203
Q

All limbs begin as what

A

a limb field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
204
Q

What is a limb field

A

limb fate map

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
205
Q

What occurs within the limb fate map on a cellular level

A

limb forming cells + limb inducing cells

206
Q

What type of interaction occurs between limb forming and limb inducing cells

A

reciprocal interaction

207
Q

What type of development is limb development

A

regulative, very flexible, not fixed

208
Q

The limb forming and inducing cells form in what

A

concentric circles

209
Q

Where are the limb forming cells in the concentric circles

A

anterior edge of circle

210
Q

Where are the limb inducing cells in the concentric circle

A

in the middle

211
Q

What does the concentric circle produce

A

one limb on each side

212
Q

If a concentric circle splits on one side what occurs

A

two limbs form on one side

213
Q

What week of development do limb buds start forming

A

5th week of human development

214
Q

The limb bud has what covering

A

ectoderm

215
Q

What occurs following the production of the initial bud

A

mesenchyme cells condense in the forming bud

216
Q

Where do the mesenchyme cells come from

A

the hypaxial myotome of the somite

217
Q

What do the mesenchyme cells form in the limb bud

A

muscles on the outside of the bones

218
Q

Once the hypaxial myotome cells aggregate, what occurs

A

they secrete FGF10

219
Q

Does the FGF10 make them aggregate

A

no they aggregate in response to something else

220
Q

What is the thing that makes them aggregate

A

unknown

221
Q

What dictates what limb is formed

A

concentration gradient and expression of HOX genes

222
Q

What dictates formation of an arm

A

noggin and OTX2 expression

223
Q

What dictates formation of a leg

A

BFGF production on the posterior end

224
Q

What does equal concentrations of noggin OTX2 and BFGF produce

A

flank

225
Q

What is a flank

A

no limb formation, flat layer of skin

226
Q

What HOX genes code for a flank

A

b9 =c9 production

227
Q

What HOX genes code for a leg bone production

A

d9=c9>b9

228
Q

What HOX genes code for an arm

A

d9>b9>c9

229
Q

What forms the bone in limbs

A

somatic plate mesoderm starts cartilage

230
Q

In the proximodistal axis, the mesenchyme cells induce the formation of what

A

apical ectodermal ridge

231
Q

What is the apical ectodermal ridge

A

ridge of elongated cells along the anterio-posterior axis

232
Q

What does the apical ectodermal ridge correspond with

A

finger tips

233
Q

what does the ridge induce

A

mesencyme cels to proliferate

234
Q

As the mesenchyme cells proliferate, what occurs

A

they push AER outward

235
Q

The cells that are proliferating are in what area of the limb bud

A

the progress zone

236
Q

The AER and the progress zone are always on what end of the limb

A

the distal end

237
Q

The first mesenchyme cells are on what axis

A

proximal axis

238
Q

What parts of the bone are formed first

A

proximal bones

239
Q

What is the last portion of bone finished

A

distal end bones and muscles

240
Q

How are joints formed

A

unknown mechanism

241
Q

All of cell proliferation requires what

A

blood supply

242
Q

What is needed to provide the blood supply

A

angiogenesis

243
Q

How does angiogenesis occur

A

branches of dorsal aorta

244
Q

If no blood vessels what occurs

A

no limbs are formed

245
Q

What drug was used in teh 1960s for morning sickness

A

thalidimide

246
Q

What was a side effect of the thalidimide drug

A

blocks angiogenesis=blocked limb formation

247
Q

What did children of mothers that took thalidimide have instead of limbs

A

flippers, hand attached to the shoulder, no limb

248
Q

When is limb formation initiated along the dorsoventral axis

A

before the limb bud is formed

249
Q

What occurs to the ectoderm for limb formation

A

it becomes dorsalized

250
Q

What is dorsalized ectoderm

A

cells are induced to end up on the dorsal side

251
Q

Dorsalized ectoderm expresses what

A

Wnt-7a

252
Q

What causes the dorsal ectoderm to move on the dorsal side

A

as limb bud grows it pulls it to the dorsal side

253
Q

What occurs to other cells on the ectoderm

A

they are induced to be ventral side cells

254
Q

What is the space between the dorsal and ventral cells of the ectoderm

A

future AER

255
Q

Due to the concentration gradient of Wnt-7a, what does the dorsal side develop

A

knuckles, nails,

256
Q

What causes knuckles and nails to form

A

expression of radical fringe TF

257
Q

On the ventral side how much WNT7a is there

A

very little to none

258
Q

What do the cells that do not get WNT7a express

A

transcription factors engrailed 1

259
Q

What does engrailed 1 produce

A

palms and pads

260
Q

without WNT-7a, what would occur to the dorsal and ventral sides

A

they would both be ventral and express pads

261
Q

The anterior posterior axis of the limb distinguishes what

A

thumb vs pinky

262
Q

In the posterior edge of the limb bud, what occurs

A

zone of polarizing activity

263
Q

What does the zone of polarizing activity do

A

polarize the pole

264
Q

What is causing this polarization

A

SHH is being secreted by the cells in the region

265
Q

What does SHH being secreted on one end create

A

a concentration gradient

266
Q

This causes the limb to be divided into what

A

5 concentration sections

267
Q

In each section what occurs

A

HOX genes are expressed in varying degrees

268
Q

In the highest concentration on the posterior end what HOX genes are expressed

A

HOX d9/10/11/12/13

269
Q

What does the highest concentration end produce

A

pinky and everything on edge of arm

270
Q

What does the second highest concentration have for HOX genes expressed

A

HOX d9/10/11/12

271
Q

What does the second highest concentration produce

A

the ring finger

272
Q

What does the mid concentraiton have for HOX gene expression

A

HOX d9/10/11

273
Q

What does the mid concentration produce

A

middle finger

274
Q

What does second lowest concentration have for HOX genes

A

HOX d9/10

275
Q

What does the second lowest concentration produce

A

index finger

276
Q

What does lowest concentration produce

A

thumb

277
Q

What HOX genes make thumb

A

HOX d9

278
Q

The concentration and finger formation initially forms what

A

a solid hand

279
Q

What defines each finger

A

apoptosis of cells between

280
Q

What are conjoined fingers or toes called

A

webbed, syndactyly

281
Q

Initially, how do all limbs begin

A

outward, no bending ventrally or dorsally

282
Q

What occurs to the upper limbs after formation

A

rotate 90 degrees to have elbows point backwards

283
Q

What occurs to the lower limbs after formation

A

rotate 90 in the opposite direction to point bend ventrally

284
Q

What two things produce neurons

A

neural tube, neural crest cells

285
Q

How do neurons generally reach specific target cells

A

elongate

286
Q

What are the two typical target cells

A

muscle or another neuron

287
Q

Why is it best for the neurons to connect to their target cells in an embryo stage

A

neurons are close to their targets as the embryo is small

288
Q

What is constructed between the neuron and its target

A

synapse

289
Q

Throughout life, what occurs to synapses

A

the number and strength are adjusted

290
Q

What is the rate at which neurons are produced

A

250,000 per minute

291
Q

In total, how many neurons are produced during the embryo stage

A

2 billion

292
Q

In comparison to the adult, 2 billion neurons is what

A

2x as many as the neurons the adults have

293
Q

Why does the embryo produce 2x the number of needed neurons

A

body errs on the side of having too many, rather than too few as some cell will not make it, they will be defected, or commit suicide and be pruned

294
Q

What is the mechanism towards which neurons extend

A

unknown

295
Q

What is the length per day that neurons extend to

A

1mm a day

296
Q

Does nerve regeneration occur in adults

A

yes, but it takes a lot of time

297
Q

Where does outgrowth of neurites toward target cells occur

A

axon or dendrite growth is at the tip

298
Q

What is the area on the axon or dendrite that extends called

A

growth cone

299
Q

What is the growth cone/ what shape

A

a slightly enlarged area shaped like a hand

300
Q

What does the hand shaped growth cone also have

A

cytoplasmic extensions

301
Q

What are the cytoplasmic extensions on the growth cone called

A

microspikes or filopodia

302
Q

What is the function of microspikes

A

transient feelers that probe the growth cone’s environemnet

303
Q

What are the microspikes probing for

A

adhesive molecules on cell or substrate surfaces

304
Q

What are the adhesive molecules that the microspikes are probing for

A

CAMs and SAMs

305
Q

What occurs when the microspike encounters a non-adhesive or repellant molecule

A

the microspike rapidly withdraws

306
Q

When an adhesive molecule is contacted, what does the microspike do

A

attaches and a new growth cone is set up at the location

307
Q

In vivo, what serves as barriers for neuron extensions

A

ECM with collagen, ect. that it must break through

308
Q

What path does the growth cone follow

A

path of greatest adhesion

309
Q

How does the neuron get through collagen and ECM

A

secretes proteases

310
Q

What are axons packed with that also aid in the breaking through of collagen and movement

A

microtubules

311
Q

How do microtubules aid in moving through ECm

A

generate a ton of force to allow axons to “punch” through

312
Q

What forms the path of adhesive molecules which a growth cone follows

A

a continuous pathway of ECM molecules
guidepost cells
contact guidance
chemotaxis

313
Q

Neurons that follow a continuous pathway of ECM molecules will require what

A

SAMs

314
Q

What is another name for the continuous pathway of ECM molecules

A

pathway guidance

315
Q

1 neuron will attach to what

A

1 target cell

316
Q

What is the basis for neural pathology

A

if a neuron does not reach its target cell and the affect this has on a disease

317
Q

The pathway guidance is around for how long

A

transient pathway, available only for a short time

318
Q

Is only one molecule used for the pathway guidance for one neuron

A

no, the ECM molecules may be used repeatedly at different locations and times to lead a series of neurons to targts

319
Q

What gene regulates migration and GABA production

A

HOX genes

320
Q

What is the pathway that involves guidepost cells

A

spots of adhesive ECM are secreted by guidepost cells

321
Q

Are the guidepost cells secreting a continuous pathway

A

no, it is spots

322
Q

How does the growth cone find the guidepost cells

A

extremely long microspikes are sent out in all directions

323
Q

In the guidepost cell method what occurs when one microspike binds to a substrate

A

the other microspikes collapse and the one that binds is maintained

324
Q

Once the neuron is filled in to a guidepost, what occurs

A

a new growth cone is set up to search for the next guidepost cell

325
Q

The first neuron to use a guidepost cell method is called what

A

pioneer cell

326
Q

Different combinations of guidepost cells can do what

A

direct axons toward different targets

327
Q

How do neurons use contact guidance to get to a target cell

A

axons going to the same region as a pioneer cell show high affinity towards them

328
Q

What mediates contact guidance pathway

A

CAMs or cadherins

329
Q

Cams or cadherins allow for what

A

cell to cell adhesion

330
Q

How long does the contact guidance pathway work for

A

until the axon of the pioneer cell is myelinated

331
Q

What about myelin prevents contact guidance pathway

A

NOGO protein

332
Q

What does the NOGO protein do

A

blocks regeneration of neurons and their ability to follow pioneer cells

333
Q

What is the name of the neurons that follow pioneer cells

A

secondary cells

334
Q

At some point during the contact guidance pathway what occurs to secondary cells

A

the secondary cells veer off

335
Q

What causes the secondary cells to veer off

A

BMP lures it away

336
Q

What is an example of contact guidance pathway

A

autonomic nervous system

337
Q

Organs are innervated by both what

A

parasympathetic and sympathetic neurons

338
Q

What is the pioneer cell between parasympathetic and sympathetic neurons

A

sympathetic

339
Q

What direction do sympathetic neurons send signals

A

from the spinal cord to the organ

340
Q

What direction does the parasympathetic neuron travel

A

from organ to spinal cord

341
Q

How does the parasympathetic neuron innervate the spinal cord

A

follows the sympathetic neuron using contact guidance

342
Q

What is a nerve

A

a bundle of axons

343
Q

What method creates a nerve

A

pioneer cells followed by secondary cells

344
Q

Failed connections between neurons would lead to what of the neuron

A

apoptosis, as it is not being used and the cell trims any pathway not being used

345
Q

What is the fourth mechanism that takes over as a growth cone approaches its target

A

chemotaxis

346
Q

How do cells move in chemotaxis

A

movement is towards the direction of highest concentration of some soluble signaling molecule

347
Q

What secretes the soluble signaling molecule

A

a target cell

348
Q

What is the general name for a soluble signaling molecule

A

chemotactic factor

349
Q

Since the chemotactic factor is referencing for neurons, what is the name of the soluble signaling molecule

A

neurotrophic factor

350
Q

What is an example of neurotrophic factors forming specific neurons

A

interneuron formation in the spinal cord

351
Q

what does the word neurotrophic factors mean

A

feeding neurons

352
Q

What is the meaning of determined

A

fate is set

353
Q

What is the meaning of differentiated

A

cell is acting out its fate

354
Q

What attracts growth cone from interneuron to move towards the motor neuron

A

the neurotrophic factor netrin

355
Q

What produces netrin

A

floor plate cells

356
Q

netrin is not only a neurotrophic factor but also what

A

growth factor

357
Q

What are the functions of netrin

A

support the neuron, keeps it alive

358
Q

In mice, what neurotrophic factor contributes to Alzhiemers disease

A

reelin

359
Q

If neurons are not kept alive, what occurs

A

they die and are removed

360
Q

What other cell do neurotrophic factors stimulate

A

oligodendrocytes

361
Q

Whern oligodendrocytes are signaled, what occurs

A

they myelinate the axons

362
Q

If there is not enough neurotrophic factor to stimulate oligodendrocytes, what occurs

A

not enough myelin

363
Q

What causes the establishmet of a synapse between the axon and its target cell

A

reciprocal interaction, exchange of signals between pre and post synaptic membranes

364
Q

When the target cells secrete NTF, what occurs to the neuron

A

it attaches to the surface of the neuron to put in calcium channels

365
Q

What is the function of the calcium channels in the membrane

A

when an AP comes down the neuron it opens the calcium channels to open and allow neurotransmitter vesicle release

366
Q

How does the target cell respond to the release of neurotransmitters

A

clusters NT receptors on the side of the cell exposed to the highest concentration of NT

367
Q

How were the receptors for the neurotransmitters prior in the membrane

A

distributed more or less ecenly over the whole cell

368
Q

Why were the NTRs spread evenly over the whole cell

A

target cell did not know which direction its axon would come from

369
Q

Once the growth cone and the target come into contact, what occurs to the growth cone

A

it become the nerve terminal

370
Q

What is joined between the target cell and nerve terminal

A

junctional complex

371
Q

What is the junctional complex

A

an ECM pad

372
Q

What function does the ECM pad

A

both cells adhere to maintain a connection without the two synaptic membranes having to come into contact

373
Q

What are the components of the ECM pad

A

Dok-7 and agrin procteins

374
Q

What does the neuron membrane have to connect to the ECM pad

A

neurexin

375
Q

What do target cells have to connect to the ECM pad

A

neuroligin

376
Q

What does mutant neuroligin cause in mice

A

autism like cells

377
Q

In strengthening the synapse with more receptors, where are NTRs sent

A

directly to the synapse rather than to the other membranes of the cell and moving later

378
Q

What is pruning of synapses do

A

activity-dependent synapse elimination

379
Q

Why is pruning of synapses activity dependent

A

inactive synapses are disconnected, while more used ones are maintained

380
Q

Synapses used frequently undergo what

A

strengthening

381
Q

Strengthening and Pruning of synapses forms the basis for what

A

memory formation and memory loss

382
Q

How are synapses strengthened

A

more agrin in ECM
increase in neurotransmitter concentration
nerve terminal can expand and split into boutons
formation of ECm net arround synapse

383
Q

How does more agrin in ECM strengthen synapse

A

stronger pad between

384
Q

How does an increase in neurotransmitter concentration strengthen synapse

A

strong response by a target cells, more channels opened

385
Q

How does nerve terminal expanding and splitting into more boutons strengthen the synapse

A

more surface area for more areas of contact

386
Q

How does the formation of ECM net arround synapse strengthen the synapse

A

holds synapse together so the synapse is retained

387
Q

What is the level of genetic variation among neurons

A

enormous diversity

388
Q

When looking at the neurons within a brain what is observed

A

the brain is a mosaic of neurons, huge areas in the brain are different from other areas

389
Q

Most of the variation is in what part of the chromosome

A

heterochromatin

390
Q

What is heterochromatin

A

non-coding regulatory regions of the chromosome

391
Q

While the gene looks normal, if the heterochromatin is off what occurs

A

expression regulation is off and does not work properly.

392
Q

What is the last stage of development

A

senescence

393
Q

What is senescence

A

deterioration of the body leading to natural death

394
Q

What causes senescence

A

cell malfunction, deterioration, or death

395
Q

What does senescence cause

A

changes visible on the outside of the body mirrors the changes happening on the inside

396
Q

What are symptoms of senescence

A 
gray hair
skin cracked and leathery
cataracts form
muscles atrophy
osteoarthritis
menopause
atherosclerosis
osteoporosis
hearing loss
slowed would healing and immune response
diabetes
nervous system problems
increased risk of cancer
397
Q

What cell gives pigment to the hair

A

melanocytes

398
Q

What replaces melancytes when they die out

A

melanocyte stem cells

399
Q

Once melanocyte stem cells are gone and melanocytes are gone what occurs

A

no pigment

400
Q

What leads to cracked and leathery skin

A

elastin fibers are being replaced with collagen

401
Q

What causes collagen to form on the skin

A

UV radiation and sunburn damage the skin and lead to “scar tissue formation”

402
Q

What causes cataracts

A

cells on the interior of the lens die

403
Q

What causes muscle atrophy

A

myoblast and sattelite cells are being removed

404
Q

What causes osteoarthritis

A

articular cartilage has worm out

405
Q

What typically replaces articular cartilage

A

chondrocytes stem cells

406
Q

Once chodrocytes are gone what occurs

A

cartilage cannot be replaced

407
Q

What causes menopause

A

oogonia stem cells are gone

408
Q

What does the removal of oogonia cause

A

no more follicles, no more estrogen

409
Q

What causes atherosclerosis

A

collagen replaces elastin in the arteries

phospholipids are replaced with cholesterol

410
Q

What occurs to cholesterol to cause damage in the arteries

A

leads to damage, inflammation, swelling, blocking and scar tissue buildup

411
Q

What effects does inflammation and scar tissue have on arteries

A

decreased vesicle radis

412
Q

How does decreased vesicla radius affect MAP

A

increases arterial pressure

413
Q

What is the #2 cause of death if you include abortion

A

coronary artery disease

414
Q

What is the #1 cause of death if you do not include abortion

A

coronary artery disease

415
Q

What is the #3 cause of death

A

stroke

416
Q

What causes osteoporosis

A

the balance between osteoblast and osteoclast is heavily weighted towards osteoclast activity

417
Q

In middle age what is the relationship between osteoblast and osteoclast activity

A

equal

418
Q

In development what is the relationship between osteoblast and osteoclast activity

A

heavy on the osteoblast activity

419
Q

What causes hearing loss

A

ear drum hardens

graying of hair in cochlea

420
Q

How does the ear drum harden

A

less elastic, doesn’t stretch or vibrate as much

421
Q

How does graying of hair in cochlea lead to hearing loss

A

once out of hair stem cells, no new hair you can’t hear

422
Q

What is the hair in the ears

A

cilia

423
Q

What is the #8 leading cause of death

A

pneumonia and influenza

424
Q

What is the #6 cause of death

A

type 2 diabetes

425
Q

What causes type 2 diabetes in elderly individuals

A

impaired glucose regulation, no longer store glucose

426
Q

Why can someone no longer store glucose

A

ran out of adipose cells

427
Q

Type II diabetes is what kind of diabetes

A

non-insulin dependent

428
Q

What is the #2 leading cause of death

A

cancer

429
Q

What is the #7 leading cause of death

A

alzheimers and parkinsons

430
Q

Most of the top deaths are what age related

A

old age

431
Q

Why do christians believe senescence happens

A

the curse, the wages of sin is death, eat from the tree and you will die

432
Q

What are suggested secondary causes to senescence (hypothesis)

A

mutation accumulation hypothesis
antagonistic pleiotrophy hypothesis
disposable soma hypothesis

433
Q

What is the mutation accumulation hypothesis

A

random mutation accumulate throughout life and are passed on to daughter cells

434
Q

Where do the random mutations come from

A

environmental factors and errors in DNA replication and repair

435
Q

What does the accumulation of these mutations cause

A

stem cells die off or cause cancer development

436
Q

What is the antagonistic pleiotrophy hypothesis

A

genes that promote reproduction early in life have the side effect of contributing to senescence later in life

437
Q

What is the side effect of reproduction

A

senescence

438
Q

What is pleiotrophy

A

a single gene leads to multiple conflicting effects

439
Q

How is testosterone pleiotrophy

A

promotes sperm reproduction to build strong muscles, but also contributes to prostate cancer

440
Q

How is estrogen pleiotrophy

A

promotes reproduction, enhances immune system to protect offspring but also leads to autoimmune diseases

441
Q

What is the disposable soma hypothesis

A

bodies exist to produce germ cells, once the job is done the body serves no purpose

442
Q

What does evolution not save

A

useless things

443
Q

What does evolution save

A

only those things which confer a reproductive advantage

444
Q

Why is an old body useless

A

maintaining and repairing an old body would take too much energy

445
Q

Prior to the flood, how long did people live

A

1000 years

446
Q

After the flood, humans live how long

A

120 years

447
Q

Who was the last oldest person

A

Joseph

448
Q

How old did joseph live to be

A

124 years

449
Q

What genes are responsible for mutations to accumulate

A

DNA, RNA, and protein repair genes

450
Q

What does mutations in the DNA, RNA, and protein repair genes lead to

A

proteins not being repaired

451
Q

What occurs when proteins are not repaired

A

they accumulate inside cells and lead to cell death

452
Q

What diseases feature proteins aggregating

A

Alzheimers and Parkinsons

453
Q

What is one gene known to be involved in aging

A

WRN gene

454
Q

What is the WRN gene named for

A

Werner’s syndrome

455
Q

What is werner’s syndrome

A

people visibly age at an accelerated rate

456
Q

People with werner’s syndrome typically die at what age

A

47

457
Q

What does the WRN gene code for

A

helicase enzyme

458
Q

If the helicase gene is mutated what occurs

A

DNA doesn’t unwind, no proteins no repair, less replication of stem cells

459
Q

What role does helicase function as

A

unwinds DNA, reproduction

460
Q

What is another accelerated aging disease

A

progerias

461
Q

Who is affected by progerias

A

children

462
Q

When do children with progerias die

A

within their teens

463
Q

Children with progeria have a mutation in what

A

insulin signaling gene

464
Q

This gene produces a mutated what

A

lamin

465
Q

What is lamin

A

a protein that lines the inside of the nuclei

466
Q

If lamin is mutated, what occurs

A

disorganized chromosomes

467
Q

What is the most impressive and easily reproducible way of extendin the life spand of mice, rats, and hamsters

A

calorie restriction

468
Q

What is calorie restriction

A

reduction in calories of an otherwise complete and balanced diet

469
Q

What did calorie restriction lead to health problems wise

A

less frequenct atherosclerosis, auto-immunity and cancer

470
Q

Calorie restriction idea has caused people to form what

A

calorie restriction society

471
Q

because calorie restriction how is energy diverted

A

distributed towards survival rather than reproducing

472
Q

In humans what does calorie restriction lead to

A

delayed menstruation

473
Q

What shows correlations with calorie restriction

A

insulin levels and concentration are dependent upon calories

474
Q

What genes prodect us from starvation

A

starvation avoidance genes

475
Q

How do starvation avoidance genes contribute to senescence

A

when these genes are damaged or underexpressed

476
Q

What is hormesis

A

minor stressors that get you cell’s guard up against other stressors

477
Q

How is calorie restriction hormesis

A

under eating is a slight stress that promotes longevity

478
Q

What are the mechanisms of senescence

A

accumulation of mutations
over-eating
oxidative stress
replicative arrest

479
Q

How does ATP generation lead to senescence

A

oxidative phosphorylation generates some nasty by-products

480
Q

What are the byproducts of oxidative phosphorylation

A

reactive oxidation species

481
Q

What are the reactive oxidation species

A

superoxide ions O2-
hydrogen peroxide H2O2
hydroxyl radicals OH

482
Q

What are strong reactive oxidation species affects

A

strong oxidizing agents that attack DNA, lipids, and proteins

483
Q

When strong reactive oxidation species attack DNA, lipids, and proteins, what occurs

A

break bonds and alter their functions

484
Q

What does breaking bonds and altering a cell’s function lead to

A

cell death

485
Q

Hydroxyl radicals can lead to the formation of what chemical group

A

carbonyls

486
Q

What is the affect of forming carbonyls rather than hydroxyl groups

A

cannot make hydrogen bonds to form protein structures

487
Q

What proteins exist to neutralize the ROS

A

superoxide dismutase
catalast
peroxidase

488
Q

What percent of all proteins are damaged by ROS forming carbonyls

A

40%

489
Q

In fruit flies, extra superoxide dismutase causes what

A

increased longevity by 35%

490
Q

What component do dietary supplements have

A

anti-oxidant actity

491
Q

What dietary supplements are antioxidant activity

A

vitamin C, vitamin E, beta carotene

492
Q

Do dietary supplements reduce risk of disease

A

no, they actually increase the risk of disease

493
Q

What is necessary to replace worn-out, damaged and lost cells

A

replication and cell division

494
Q

What are the 3 sources to replace damage

A

some cells are permanent
stable cells
adult stem cells

495
Q

What cells are permanent

A

neurons and muscles

496
Q

What are stable cells

A

liver, pancreas, kidney that can dedifferentiate

497
Q

What does dedifferentiation lead to

A

regress and divide to serve as a replacement

498
Q

How many times can stale cells divide

A

50X

499
Q

What does the amount of division stable cells can undergo make them

A

a stable source, but limited

500
Q

How many times can adult stem cells divide

A

unlimited

501
Q

Why are stable cells limited to 50X division

A

every time a cell divides, part of the telomere gene is cleaved off

502
Q

After 50X division, what occurs to the telomere gene

A

the telomere gene is gone and cannot acquire

503
Q

fetal cells in culture will replicate how many times

A

50X

504
Q

cells from and 80yo will replicate how many times

A

28 X

505
Q

cells from someone with werners syndrome will replicate how many times

A

20X

506
Q

how are adult stem cells able to replicate unlimitedly

A

they experess telomerase

507
Q

What is the function of telomerase

A

replaces the tips of chromosomes to protect telomere gene

508
Q

What other cells express telomerase

A

cancer cells

509
Q

Even if cancer cells do not express telomerase, what can occur

A

still get a big cancer

510
Q

In mice that had a knockout of telomerase, what occurred

A

they died prematurely, showed spleen atrophy and slow wound healing

Embryology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions