Development Flashcards
1
Q
What is developmental biology? (4)
A
- the study of how a fertilised egg becomes an adult organism
- how an adult organism reproduces
- how an organism ages and dies
- how an organism repairs and replaces cells and tissues after damage/under normal conditions
2
Q
why does the study of development matter?
A
- better understanding of congenital birth defects
- leads to new and more effective treatments for human diseases (regenerative medicine)
- evolutionary development (better understanding of evolution)
3
Q
what has allowed us to study developmental biology?
A
model organisms
4
Q
what are the 2 types of model organisms?
A
- protosomes
- deuterostomes
5
Q
what does proto mean?
A
first (greek)
6
Q
what does deutero mean?
A
second (greek)
7
Q
what does stoma mean?
A
mouth (greek)
8
Q
what’s a protostome?
A
organism in which the mouth forms first
9
Q
what’s a deuterostome?
A
organism in which the mouth forms second
10
Q
by which name is arabidosis thaliana better known?
A
thale cress
11
Q
give 3 benefits of the use of arabidosis thaliana
A
small easy to grow short generation time (genetics) embryology good imaging sequenced genome transgenic plants can be made using agrobacterium
12
Q
by what name is dictyostelium discoideum better known?
A
slime mould
13
Q
is slime mould a proto or deuterostome?
A
proto
14
Q
give 3 benefits of the use of dictyostelium discoideum
A
multicellular chemotaxis genetics sequenced genome transgenesis social behaviour (altruism) looks/behaves similarly to phagocytes
15
Q
are hydra proto or deueterostomes?
A
proto
16
Q
what are 3 benefits of the use of hydra?
A
- radial symmetry
- diploblastic (double bud- endo and ectoderm)
- small
easy to grow
sexual and asexual reproduction
high regenerative capacity
17
Q
what are Planaria better known as?
A
flatworm
18
Q
are flatworms proto or deuterostomes?
A
proto
19
Q
give 3 benefits to using flatworms
A
adult stem cells- regenerative capacity
sexual and asexual reproduction
triploblastic- endo, ecto and mesoderm
20
Q
by what name are caenorhabditis elegans better known?
A
round worm
21
Q
are round worms proto or deuterostomes?
A
proto
22
Q
give 3 benefits of using round worms
A
- have few cells short generation time 2 sexes genetics and transgenics study of ageing- short lifespan RNA knockout technology sequenced genome lineage of cells known imaging
23
Q
by what name are drosophila melanogaster better known?
A
fruit flies
24
Q
are fruit flies proto or deuterostomes?
A
proto
25
give 3 benefits of using fruit flies
```
short generation time
genetics
transgenesis
sequenced genome
imagery
segmental
athropod
```
26
by what name are parhyale hawaiensis better known?
amphipod crustacean
27
are amphipod crustaceans proto or deuterosomes?
proto
28
give 3 benefits of using amphipod crustaceans
```
- athropods
short generation time
genetics
sequenced gemone
high regenerative capacity
transgenesis
transparent
```
29
by what name are stronglyocentrotus purpuratus better known?
sea urchins
30
are sea urchins proto or deuterostomes?
deutero
31
give 3 benefits of using sea urchins
```
-imaging
produces many eggs
transparent embryos
injection of nucleic acids
basal deuterostome
```
32
by what name are ciona intestinalis better known?
sea vase
33
are sea vases proto or deuterostomes?
deutero
34
give 3 benefits of the use of sea vases
```
transgenesis
genetics
sequenced genome
imaging
basal chordate
spinal cord
inverterbrae
```
35
are brachiostoma lanceolatum proto or deuterostomes?
deutero
36
give 3 benefits of using brachiostoma lanceolatum
sequenced genome
invertebrate
basal chordate
37
by what name are danio rerio better known?
zebrafish
38
are zebrafish proto or deuterostomes?
deutero
39
give 3 benefits of zebrafish
```
genetics
sequenced genome transgenesis
imaging
regulation capacity
external development
vertebrate
```
40
are frog embryos proto or deuterostomes?
deuterostomes
41
give 3 benefits of using frog embryos
```
embryology
generated in large numbers
transparent tadpoles
easy to make explants and perform transplantations
transgenic
pancreas present
regeneration
```
42
what are gallus gallus?
chicks
43
are chicks proto or deuterostomes?
deuterostomes
44
give 3 benefits of using chicks
transplantation experiments
sequenced genome
overexpression and knock out experiments
45
by what name is Mus musculus better known?
mouse
46
are mice proto or deuterostomes?
deutero
47
give 2 benefits of using mice
strong genes
| mammal
48
give 3 benefits of using homo sapiens
genetics
mammal
sequenced genome induced pluripotent embryonic stem cells
49
how many thoracic segments in adult fruit flies?
3
50
where are the notum and wings found on a fly?
the 2nd thoracic segment
51
where are the halters found on a fly?
the 3rd thoracic segment
52
what happens when there's a mutation in the bithorax complex?
the 3rd thoracic segment can be transfotmed into the 2nd thoracic segment, therefore there are 2 2nd thoracic segments
53
what are homeotic mutations?
where one body part has been transformed into another
54
where are genes for mutant and non-mutant parts of the fruit fly found?
in the same region of the chromosome
55
in what were hox genes first identified?
in drosophila
56
what did hox genes cause in drosophila?
homeotic mutations/transformations
57
hox genes are evolutionarily conserved, what does this mean?
they've remained essentially unchanged throughout evolution
58
what's the homeodomain?
the region on a protein that binds to the DNA
59
where are hox genes found?
clustered in the genome
60
what's tandem gene duplication?
where unequal crossover is caused by a chromosome mispairing at meiosis, possibly due to repeated DNA sequences
61
what are paralogous genes?
duplicated genes within a single genome
62
what are orthologous genes?
the same gene in different organisms
63
what are homologous genes?
genes that share a single common ancestor
64
what does it mean when genes are duplicated in tandem?
each is the same as the last
65
if each gene is the same as the last, what is there?
redundancy
66
if there's redundancy in the genes is it ok if one is lost? why?
yes as there's no selection pressure for the genes to be there
67
what do the genes in tandem acquire new functions over time?
new functions
68
is it ok if one of the genes with a new acquired function is lost?
no as the genes are different so there isn't simply the same gene to replace it
69
what is subfunctionalization?
a neutral mutation process where no new adaptations are made
70
what are the 2 mechanisms of subfunctionalization?
change in protein sequence
| change in time/place of gene expression
71
what's segmental duplication?
a big tandem duplication affecting a whole chunk of chromosome
72
what can tandem and segmental duplication events give rise to in drosophila?
2 hox clusters
73
by what 2 mechanisms can whole genome duplication events occur by?
- allotetraploidy
| - autotetraploidy
74
what's allotetraploidy?
hybridization between 2 separate species
75
what's autotetraploidy?
duplication of genome through improper meiosis- instead of haploid germ cells, there are diploid germ cells giving tetraploid organisms
76
diplo meaning
2
77
triplo meaning
3
78
zoa meaning
life
79
blast meaning
bud
80
derm meaning
skin
81
noto meaning
back
82
endo meaning
inside
83
meso meaning
middle
84
ecto meaning
outside
85
meta meaning
after
86
chord meaning
string/rope
87
uro meaning
tail
88
cephalo meaning
head
89
echino meaning
spiny/prickly
90
protozoan meaning
first/primitive life
91
metazoan meaning
multicellular animals
92
diploblastic meaning
containing 2 tissue layers
93
triploblastic meaning
containing 3 tissue layers
94
endoderm meaning
tissue (germ layer) on the inside
95
what does the endoderm give rise to?
internal organs
96
mesoderm meaning
tissue (germ layer) in the middle
97
what does the mesoderm give rise to?
notochord, muscle etc
98
ectoderm meaning
tissue (germ layer) on the outside
99
what does the ectoderm give rise to?
skin and nervous system
100
chordate meaning
animal without notochords
101
notochord meaning
chord in the back
102
urochordate meaning
animal with notochord in their tails
103
cephalochordate meaning
animals with notochord extending to their heads
104
echinoderm meaning
prickly skin
105
give an example of an echinoderm
sea urchin
106
what is descriptive embryology?
- experiments which aim to define normal embryonic development with minimal disruption of the process
- leads to an understanding of what happens during development- but not how
107
what is experimental embryology?
- experiments which aim to define how embryonic development occurs e.g. how and when cells acquire their fate
- requires experiments that perturb normal development- manipulations
e. g. transplantation studies to find whether the cell or its surroundings controls outcome
108
what's morphogenesis?
process by which form is generated- involves coordinated cell movement
109
what's gastrulation?
morphogenic process by which the ectoderm, mesoderm and endoderm layers reach their final position in embryo
110
morpho meaning?
shape/form
111
genesis meaning?
birth/origin
112
what's neurulation
morphogenic process by which the nervous system begins to form- especially formation of neural tube
113
what's a blastomere?
a cell in the early embryo
114
what's a fate map?
- assessment of the fate of a cell/group of cells based on lineage labelling
- answers question- what will this cell become if left to develop undisturbed in embryo ?
115
what part of embryology is a fate map part of?
descriptive
116
what's a specification map?
- assessment of what a cell or group of cells will form into if removed from their embryonic environment (neighbouring cells)
- asking what a cell 'thinks' it should become when isolated from neighbours
117
what part of embryology is a specification map part of?
experimental
118
what is meant by determined?
cell/tissue is determined if it will still develop according to its fate, even when transplanted into another site in the embryo (a new environment)
119
what is meant by competence?
the range of cell fates which can be achieved by a cell/group of cells given the appropriate conditions (what it is capable of becoming)
120
what's induction?
the process by which a cell/group of cells emits signals to its neighbouring cells, thereby changing their fate
121
what was done in the organizer experiment 1924?
took dorsal mesoderm from newt embryo and put into the ventral side of the other embryo --> gave siamese twin embryo
122
what's homeotic mutation?
mutation which results in the transformation of one body structure into another
123
what is a hox gene?
a family of genes which encode related transcription factors characterised by containing a DNA binding domain- the homeodomain/homeobox
evolutionary conserved
124
where were hox genes first identified?
drosophila
125
what did the hox genes show in the drosophila?
they are involved in anterior posterior patterning
126
what can mutations in hox genes lead to?
homeotic mutation
127
where are hox genes found?
clustered in the genome
128
what's colinearity?
genes in the 3' end are expressed progressively earllier and more anteriorly that genes in the 5' end of the cluster
129
what are the 3 sources of evidence for the effects of hox genes?
- expression pattern
- comparative embryology
- gene knockout experiments
130
what are somites?
mesoderm derivative
| segmental blocks of tissue forming from anterior to posterior
131
what do somites give rise to?
muscles, vertebrae and dermis of the skin
132
what are homologous genes?
genes that share a common ancestral gene
133
what are paralogous genes?
duplicated genes within a single genome
134
what are orthologous genes?
same gene, different organism
135
what is gene redundancy?
situation where no phenotype is observed when a gene is mutated because another gene can replace/substitute the function of the mutated gene
masks the role of a mutated gene
136
what do phenotypes arising from mutation show?
what the gene is required for
137
what are the 3 modes of gene duplication?
tandem
segmental
whole genome
138
what causes tandem gene duplication?
chromosomes mis-pairing at meiosis, possibly caused by repeat DNA sequences
139
what's segmental gene duplication?
giant tandem duplication (whole chunk of chromosome)
140
what are the 2 whole genome duplication events called?
allotetraploidy
| autotetraploidy
141
what's potency?
the range of cell fates available to a cell or a group of cells (similar to competence)
142
what's totipotent?
cells that can give rise to all cells in the embryo- even extra embryonic membranes+ tissues
143
what's pluripotent?
cells that can give rise to most, but not all cells in the embryo
144
what's bipotent?
cells that can give rise to 2 cell types
145
what's unipotent?
cells that can give rise to 1 cell type
146
what did mangold and speman do?
discovered the organiser
147
what did speman do?
discovered nucleus at 16 cell stage was totipotent
148
what did briggs and kings do?
first to successfully transplant nuclei into eggs
149
what did gordon do?
first to clone an adult animal through nuclear transplantation
150
what did cambell and wilimit do?
first to clone a mammal (dolly)
151
what did martin evans do?
first to isolate and culture embryonic stem cells from mouse embryos
152
what did shinya yamanka do?
first to successfully indice pluripotency without the need to transplant nuclei into eggs or generate embryos
153
what does the waddington landscape show?
potency decreases over time
154
what doesn't the waddington landscape show?
it's not one way, cells can be driven back up to become more potent
155
what are the three parts of the mammalian preimplantation blastocyst embryo?
epiblast
trophoblast
blastocode
156
what's the epiplast/inner cell mass?
gives rise to the embryo including the germ cells- source of pluripotent embryonic stem cells
157
what's the trophoblast?
gives rise to extraembryonic membranes including the placenta
158
what makes Human Embryonic Stem (hES) and induced Pluripotent Stem (iPS) cells valuable? (4)
- study human embryonic development in vitro
- generate organs in vitro
- model genetic diseases in vitro
- harness to treat genetic diseases in humans
159
what do adult stem cells do?
play a role in replacing cells throughout life
160
where are adult stem cells found- give 3
```
3 from
bone marrow
skin
hair follicle
gut
blood
```
161
what are stem cells sensitive to?
radiation and chemotherapy
162
what was the first successful example of stem cell therapy in humans?
bone marrow transplantation
163
what stem cells are found in bone marrow?
human hematopoietic
164
what can limbic SCs treat?
corneal injuries
165
what can keratinocyte SCs treat?
burn injuries
166
what's the beauty of using human derived induced pluripotent stem cells?
the patient themselves provides the cells- no issues in rejection (personalised medicine)
