Chapter 42 Animal Development Flashcards
1
Q
What does housing refer to?
A
Place where embryo develops.
2
Q
What does aiding and abetting the young called?
A
Feeding.
3
Q
Can skin secretions be used for feeding?
A
Yes.
4
Q
What are the 3 mechanisms of embryonic development?
A
Cleavage, gastrulation, and organogenesis.
5
Q
Where do the instructions for the development from embryo to organism come from?
A
Zygotes’ nucleus and the maternal cytoplasm.
6
Q
What directs the first stages of development in the embryo?
A
Maternal cytoplasm in zygote.
7
Q
What are the mRNA and proteins stored in cytoplasm that direct the first stages of development called?
A
Cystoplasmic determinants
8
Q
When can polarity arise?
A
Unequal distribution of yolk.
9
Q
What produces bilateral symmetry?
A
Unequal distribution of egg.
10
Q
What are the 3 axis created by polarity?
A
Dorsal-ventral, anterior-posterior, and right-left.
11
Q
What are 3 characteristics of animal pole?
A
Less yolk, faster cell division, and gives rise to surface structures and anterior part of body. (Easy to develop skin)
12
Q
What are 3 characteristics of vegetal pole?
A
Slow division, gives rise to internal structure and posterior end of body, and more yolk.
13
Q
What are the blastula cells called?
A
Blastomeres
14
Q
What is the solid ball of cells during the cleavage called?
A
Morula.
15
Q
Why doesn’t embryo size increase during cleavage?
A
Because the maternal cytoplasm content remains the same.
16
Q
What is the human blastula called?
A
Blastocyst.
17
Q
What is gastrulation?
A
Rearrangement of cells in blastula to form the 3 germ layers.
18
Q
At what stage of development is the body pattern established?
A
Gastrulation.
19
Q
At what stage of development does the archenteron formed?
A
Gastrulation.
20
Q
What is the archenteron lined with?
A
Endoderm.
21
Q
What are the 6 mechanisms controlling development?
A
Mitotic divisions, cell movement, selective cell adhesion, induction, determination, and differentiation.
22
Q
What is selective cell adhesion?
A
The phase where cells choose to break or make connections to other cells or ECM.
23
Q
What are the 4 extraembryonic membranes?
A
Amnion, chorion, yolk sac, and allantois.
24
Q
How is the yolk distributed in sea Urchin?
A
Evenly.
25
Does cleavage take place at the same rate in sea urchin?
Yes.
26
Where does invagination and gastrulation begin in sea urchin?
Flattened vegetal pole cells.
27
Determination is a product of what?
Induction
28
What triggers the primary mesenchyme to migrate into blastocoel in a sea urchin?
Inducation
29
Where does the mouth form during gastrulation in sea urchin?
Where archenteron touches the ectoderm.
30
Where do the secondary mesenchyme cells come from in sea urchin?
From the connection between archenteron to the ectoderm.
31
How is the yolk distribution in an amphibian development?
Uneven.
32
Where is the site for fertilization on a frog egg?
The grey side/ animal pole.
33
What color is the animal pole in an amphibian egg?
Grey (The dark side of humans)
34
How and where is the dorsal-ventral side established on a frog egg?
Rotation of pigment layer after fertilization. The dorsal side is the grey crescent.
35
Where does the 1st cleavage occur in from embryo?
Across the grey crescent.
36
How does a dorsal lip form?
When animal pole cells migrate to the grey crescent and create a depression.
37
Is gastrulation in frog symmetrical?
No
38
What is a major induction center in frog embryo?
Dorsal Lip.
39
What is a yolk plug?
Cells of vegetal half.
40
What is the first thin layer of cells that forms in bird embryo?
Blastodisk (disk=thin).
41
What 2 layers does the blastodisk get transformed into?
Epiblast and hypoblast.
42
What layer produces the 3 germ line cells in bird embryo?
Epiblast.
43
What kind of cell line does a hypoblast produce in bird embryo?
Germ line that lead to development of egg and sperm in embryo.
44
What is the difference between primitive groove and primitive streak?
Primitive streak is just a line when epiblast cells move towards middle of blastodisk. Primitive groove forms when the midline sinks.
45
What do the cells that move laterally from epiblast cells into blastocoel form in chick embryo?
Mesoderm.
46
What do the cells that move straight down from epiblast cells into blastocoel form in chick embryo?
Endoderm.
47
Epiblast cells that remain at the surface of embryo form what?
Ectoderm.
48
When does a coelom form in mesoderm of chick embryo?
When the ectoderm and mesoderm twist into an ohm's symbol shape.
49
Is there an archenteron in chick embryo?
Yes, after the ohm's symbol shape is fully established.
50
How are the nutrients in the yolk absorbed by the embryo?
Through the absorption from the mesoderm and endoderm.
51
Including the 6 mechanisms of development what is the 7th one which plays a factor in organogenesis?
Apoptosis.
52
Does notochord cause induction?
Yes, neural plate doesn't form without it.
53
When does organogenesis begin in vertebrates?
Neurulation.
54
From what primary germ layer does the neural tube form from?
Ectoderm
55
What do neural crest cells go on to develop?
Major organ systems.
56
What anatomical side does the primitive streak form from on birds' embryo?
From the posterior-dorsal side to the anterior-dorsal side.
57
What does mesoderm split into during organogenesis?
Somites (repeating structures).
58
What do somites give rise to?
Vertebral columns, ribs, ribs muscles, and limbs.
59
The loss of tail of adult frog demonstrates which mechanism of development?
Apoptosis.
60
Human gestation is divided into how many trimesters?
3
61
What nourished an embryo during human pregnancy?
Placenta
62
When is an embryo called a fetus?
When major organ systems form 8 weeks.
63
After how many weeks is a baby ready to be born?
40 weeks.
64
What does partuition mean?
When mother is in labour. (Baby parts from moms body)
65
What is the lining of the uterus wall called?
Endometrium.
66
What layers does a human blastocyst consists of?
Trophoblast and inner cell mass.
67
What two layers are in inner cell mass of human embryo?
Epiblast and hypoblast.
68
What gives rise to the 3 germ layers in human embryo?
Epiblast
69
What do trophoblast release to invaginate endometrium?
Proteases.
70
What does the amnion form from in human embryo?
Epiblast
71
What part of a human blastocyst becomes embryo?
Inner cell mass.
72
What conducts blood between embryo and placenta?
Umbilical cord.
73
What are chorionic villi?
Fingerlike extensions of chorion.
74
What three cellular events need regulation during development?
Cell division, cell movement, and cell adhesion.
75
What two factors have an impact on cell division?
Orientation and rate of mitosis.
76
What causes the neural plate cells to change shape from cuboidal to columnar during development?
The lengthening and sliding of microtubules.
77
What causes the wedge shape transformation in the neural tube development?
Microfilaments sliding close together and constricting.
78
What 2 mechanisms are responsible for moving cells during development?
Tracks (ECM secretions) and gradient (protein receptors).
79
What are the four basic steps for cells movement in order?
Attachment, extension, attachment, contraction
80
What does selective cell adhesion use?
Glycoproteins such as cell adhesion molecules.
81
What is an example of CAM?
Cadherins.
82
How do Cadherins work?
Set up adhesion using calcium ions.
83
What are final adhesions?
Hold the cell in its final shape and form using the 3 junctions.
84
What is induction?
When inducer cells induce responder cells to follow a particular pathway.
85
What is differentiation?
When cells become specialized from embryonic form.
86
What is differential gene activation and when does it occur?
It means that after the activation of a certain genes another set of genes can be activated from then on. It occurs during differentiation.
87
What is fate mapping?
Tracking and mapping the embryonic structure from which each larval structure is derived.
88
What techniques are used in fate mapping?
Dyes.
89
What are the master regulatory genes involved in skeletal muscle formation?
myoD, myogenin, and MEF (mother f******).
90
What are the two master regulatory genes right before skeletal muscle formation?
myogenin and MEF.
91
What transcription factor plays a role in the formation of myoblasts?
MyoD
92
How do cells know their position in the embryo?
Concentration gradients of regulatory molecules.
93
What is pattern formation?
Arrangement of organs in their proper 3-D relationships.
94
Does cytokinesis occur in embryogenesis in Drosophila?
No.
95
What help establish segmentation?
Protein gradients.
96
What 2 major sets of genes determine body plan?
Maternal-Effect genes and segmentation genes.
97
What are maternal effect genes?
Expressed by mother during oogenesis and thus in embyo.
98
What is the master regulatory gene controlling the development of thorax and head?
bicoid gene.
99
What are segmentation genes?
Subdivide embryo into regions determining segments of adult.
100
What are the 3 segmentation genes?
Gap genes, pair-rule genes, and segment polarity genes.
101
What do maternal effect genes control?
Polarity of egg and therefore the embryo.
102
What is the product of gap genes?
Divides embryo into broad anterior and posterior regions.
103
What is the product of pair rule genes?
Divide the embryo into 2 regions each.
104
What is the product of segment polarity genes?
Establish an anterior and posterior boundary to each segment of the embyo.
105
What happens during a mutation of a gap gene?
Loss of a full body segment.
106
What happens during a mutation of a pair rule gene?
Loss of one segment of a pair.
107
What happens during a mutation of a segment polarity gene?
Loss of one part of the segment and duplication of another.
108
What do homeotic genes determine?
Determine what organ each body part will become.
109
What is the full name for Hox genes?
Homeobox.
110
What do Homeobox code for?
Amino acid region of transcription factor known as homeodomain. (Box has the tools to make stuff)
111
What are the evolutionary conserved genes known as?
Hox genes.
112
What part of transcription factor binds to the promoter region of a gene (talking about homeotic genes)?
Homeodomain.
113
Are Homeotic genes master regulatory genes?
Yes.
114
What 2 proteins must be stopped from getting activated to stop apoptosis from happening?
CED-4 and CED-3
115
What is epigenetics?
Study of organisms by changing gene expression rather than genetic code.
116
What are the 3 techniques used in epigenetics?
Methylation, X chromosome inactivation, and acetylation of histones.
117
What can be used for programming cells in gametogenesis and embryogenesis to change their gene expression?
Epigenetics.
