Lab Practical 1 Flashcards

(211 cards)

1
Q

Identify the Image

Top, right side, left side

A
  1. Ocular
  2. Stage
  3. Focus
  4. Objective
  5. Condenser diaphragm
  6. Field diaphragm
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2
Q

Identify the Image

Left, Right

A
  1. Manufacturer
  2. Magnification
  3. Tube length
  4. Magnification Color Code
  5. Lens Correction
  6. Numerical Aperature
  7. Indicates Oil Objective
  8. Coverglass Thickness
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3
Q

Identify the Type of Light Microscopy

A
  1. Bright field microscopy
  2. Darkfield microscopy
  3. Phase-contrast microscopy
  4. Transmission electron microscopy (TEM)
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4
Q

Identify the Type of Light Microscopy

A
  1. Nomarski (differential interference contrast)
  2. Fluorescence microscopy
  3. Confocal laser scanning microscopy
  4. Scanning Electron microscopy (SEM)
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5
Q

What is the purpose of the objective? What is the range in magnification?

A

Provides the main source of magnification

Range in magnifications of 2.5-100x

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6
Q

What is the purpose of an eyepiece?

A

Used to view the specimen image magnified by the objective

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7
Q

What is the purpose of a stage?

A

Holds the specimen and allows for movement within the optical path of the micrscope

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8
Q

What is the purpose of focus knobs (fine and coarse)?

A

Raise and lower the height of the objective, thereby changing the plane of focus

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9
Q

What is the purpose of the condenser?

A

Focuses the light passing form the lamp to the specimen

Its height relative to the specimen is essential in establishing Köhler Illumination

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10
Q

What is the purpose of the condenser knob?

A

Raises and lowers the condenser

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11
Q

What is the purpose of a condenser diaphragm?

A

Regulates the amount of light passing through the condenser

Adjusting its diameter regulates how much light illuminates the specimens - closing condenser diaphragm can reduce scattered light traveling through the microscope, thus improving resolution

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12
Q

What is the purpose of the field diaphragm?

A

Located above the lamp housing/light source

It regulates the amount of light traveling form the lamp to the condenser

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13
Q

What is the light source?

A

Consist of a bulb which provides illumination

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14
Q

What is Köhler illumination?

A

A lighting technique so the specimen can be uniformly lit with minimal interference from the internal components of the microscope

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15
Q

What are the two focal planes established in Köhler illumination?

A
  1. The Conjugate Field Planes; back of the retina, field stop of injective, the specimen, and the field diaphragm are all in focus at once
  2. The Conjugate Aperature Plane; iris of the eye, rear focal plane of the objective, the front focal plane of the condenser, and the lamp filaments are all in focus at once
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16
Q

Light Microscopy

A

Light microscopy utilized light to illuminate the speciment

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17
Q

Bright-field microscopy

A

The specimen is illuminated with the full wavelengths of visible light and contrast in the image is provided by the specimen itself

Both live and preserved specimens can be viewed

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18
Q

How do you improve contrast with bright field microscopy?

A

If the specimens are preserved you can use a Hematoxylin and Eosin (H&E) stain

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19
Q

Dark Field Microscopy

A

The exclusion of unscattered light, thus regions that don’t scatter light (no specimen) appear black

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20
Q

If you need increased contrast of a live specimen, what microscopy technique should you use?

A

Dark Field Microscopy

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21
Q

Phase Contrast Microscopy

A

Utilizes the differences in refractive indices within a specimen to improve contrast

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22
Q

What microscopy is especially useful for viewing unstained specimens and viewing edges of structures where refractive index becomes more evident?

A

Phase Contrast

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23
Q

Differential Interference Contrast (DIC)

Aka Nomarski

A

Similar to Phase Contrast microscopy

It utilizes polarized light to create two separate coherent image components which are then recombined

The interference generated during the recombination allows for difference in refractive index to be detected, thereby creating increased contrast

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24
Q

What microscopy technique is especially useful for viewing intracellular components such as vesicles

A

Differential Interference Contrast (DIC)

aka Nomarski

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25
What are the two types of fluorescence microscopy?
1. Epifluorescence Microscopy 2. Confocal Microscopy
26
What are the three types of microscopy discussed in class?
1. Light Microscopy 2. Fluorescence Microscopy 3. Electron Microscopy
27
What are the 4 types of light microscopy?
1. Bright field 2. Dark field 3. Phase contrast 4. Differential Interference contrast (DIC)
28
What are the two types of electron microscopy?
1. Scanning Electron Microscopy (SEM) 2. Transmission Electron Microscopy (TEM)
29
Fluorescence Microscopy
Fluorescent dyes (fluorochromes) are able to absorb wavelength at a particular light and re-emit light at a slightly longer wavelength of light These dyes are then typically linked to antibodies or other compounds which bind to specific cellular structures
30
Epifluorescence Microscopy
A specimen is stained with a fluorescent dye and then illuminated with a fluorescent light source of a particular wavelength Regions of the cell with the bound dye will emit light at a specific, slightly longer wavelength
31
What are some examples of frequently used dyes for epifluorescence microscopy?
1. DAPI (illuminated by UV light and emits a blue light) 2. FITC or GFP (excited by blue light and emits green light) 3. Rhodamine/Red (excited by green light and emits a red light)
32
What is the pro and con of fluorescent microscopy?
1. Pro = allows for visualization of specific subcellular components 2. Con = Reliant on specific fluorescent dyes
33
Confocal Microscopy
utilizes lasers to illuminate the fluorescent dye only collected data from a specific defined focal plane Provides a more detailed fluorescent image
34
Electron Microscopy
Bombards the specimen with electrons
35
What is the biggest advantage of electron microscopy?
Allows for greater magnification and visualizing much smaller objects
36
In order to generate contrast in electron microscopy what needs to happen?
The specimens must be coated or stained with material with will prevent the passage of electrons
37
Scanning Electron Microscopy enables one to visualize what?
The outer surface of the speicimen
38
How does Scanning Electron Microscopy work?
The specimen is preserved and coated in a fine layer of gold When electrons are projected at the specimen, they reflect off the gold and are detected by sensors which generates the image Since the specimen is gold-coated only external details are evident
39
Transmission Electron Microscopy (TEM) enables one to view what?
Internal Structures
40
How does Transmission Electron Microscopy (TEM) work?
The specimen must be embedded in a hard resin and then cut into then secions The sections are stained with electron-opaque stains which differentially bind to various intracellular components Electrons are projected onto the specimens and will either pass through the specimens or are blocked Detectors collect the transmitted electron to generate an image
41
Preparation of specimens for _____ requires significantly more work and skill relative to ____ (electron microscopy)
TEM SEM
42
Label the Stages Of Cell Divison
M-phase Mitosis G1 S Phase (DNA synthesis) G2
43
Identify the Image
Diakinesis
44
Identify the Image Top, Left, Right
Pachytene Diakinesis Late Diplotene
45
Identify the Image
X chromosomes Leptotene
46
Identify the Image
Leptotone Zygotene Packytne Diplotene Diakinesis
47
Identify the Image Top from left to right
Leptotene Zygotene Pachytene Diplotene Diakinesis
48
Identify the Image
Prophase I, Metaphase I, Anaphase I, Telophase I Prophase II, Metaphase II, Anaphase II, Telophase II
49
Identify the Image
Metaphase
50
Identify the Image
Interphase
51
Identify the Image
Prophase Centrioles
52
Identify the Image
Prometaphase Microtubules Nuclear Membrane Breakdown
53
Identify the Image
Metaphase Metaphase Plate
54
Identify the Image
Anaphase
55
Identify the Image
Telophase Cleavage Furrow
56
Identify the Image
Pachytene
57
Identify the Image
Prometaphase
58
Identify the Image
Prophase
59
Identify the Image
Telophase
60
Identify the Image
x-chromosomes Zygotene
61
G1 Phase/ Gap 1 What is it? What is produced (4)? Length? Metabolically Active?
period of preparation for division production of: 1. Nucleotides 2. Amino acids 3. Enzyme systems 4. Reserve Engergies Long Phase Metabolically Active
62
G2 Phase / Gap II Phase What is it? What is being produced? Length?
Production of molecules necessary for mitotic development 1. Spindle fiber protiens 2. Microtubules Fairly short
63
M Phase what is it?
Separation of chromosomes followed by cell divison
64
Karyokinesis
Separation of chromosomes The first stage of mitosis or meiosis
65
Cytokinesis
separation of the cell cytoplasm resulting cells may be equal or unequal in size
66
Which phases comprise interphase?
G1-G2
67
During G1-G2 phases, can you see chromosomes?
No
68
G0
A special resting phase that terminally differentiated cells enter Divisions are halted
69
Prophase (4 primary events)
Chromosomes condense, nucleolus, disappears, centrioles replicate
70
Prometaphase (3 major events)
Nuclear envelop fragments Microtubules bind to kinetochores Non-kinetochore microtubules overlap
71
Metaphase (1 major event)
Mitotic spindle organizes and directs chromosomes to equatorial plate
72
Anaphase (2 events)
Chromatids separate Chromatids are pulled to opposite ends of cell
73
Telophase (4 events)
Nuclear envelope reforms Chromosomes uncoil and become indistinct Nucleoli reappear Cytoplasm divides
74
What happens during S period?
Chromosomes replicate again and prepare for the next division
75
The two daughter cells are mitosis are diploid or haploid?
Diploid
76
What are the stages of mitosis?
1. Prophase 2. Prometaphase 3. Metaphase 4. Anaphase 5. Telophase
77
What are the stages of Meiosis?
Prophase I Metaphase I Anaphase I Telophase I Prophase II Metaphase II Anaphase II Telophase II
78
Names have been assigned to distinguish the changing chromosomal states during prophase I stage. What are they?
1. Leptotene 2. Zygotene 3. Packytene 4. Diplotene 5. Diakinesis
79
Leptotene - distinguishing features
Chromosomes have replicated forming sister chromatids Cell in enlarged The X chromosome is condensed and seen as a dark oval on one side of the chromosomal mass
80
Zygotene (synaptene)
Begins as sister chromatids start forming synapses with their homologous pair (tetrad)
81
Tetrad
Homologous pair of sister chromatids
82
Pachytene
starts at the conclusion of synapses formation Some crossing over may happen at this stage
83
When does crossing over occur?
In the Pachytene and Diplotene stages of Prophase I
84
Diplotene
Homologous pairs start to separate (de-synapses) but remain attached at chiasmata RNA synthesis is occurring
85
Chiasmata
Regions where crossing over has occurred
86
Eggs of many species arrest at what stage?
The diplotene stage of prophase I Diplotene arrest
87
Lampbrush Chromosomes
occurs in the diplotene stages of some mammals (not humans though)
88
Diakinesis (3 main events) The nucleus is now prepared for what?
"moving apart" Contraction and repulsion continue Chromosomes detach form nuclear envelope RNA synthesis stops The nucleus is now prepared for the two critical maturation divisions
89
Why do the chromosomes look so weird (rings, crosses, bars, coils) during diakinesis?
Terminalization of chiasmata on the bivalent pairs continues during diakineses
90
Metaphase I meiosis
terminalized bivalents (doubled homologous chromosomes) line up at the equatorial plate DIFFERENT from MITOSIS (homologous chromosomes)
91
Anaphase I of Meiosis (3 events and end result)
homologous chromosomes migrate to respective poles Centrosomes have never divided Any chiasmata become free Each end of the cell now has a haploid set of chromosomes (two chromatids)
92
Telophase I
symbolically ends the first phase of meiosis THIS IS A REDUCTIONAL DIVISION
93
If cells form at telophase I what genetic makeup would they have?
They would be genetically haploid
94
Does telophase happen in all cell types?
No
95
What must happen to have a Prophase II? What does Prophase II mark?
Prophase II is only present if a telophase I and pseudo interphase are present This is the beginning of the equational division
96
Metaphase II
Centromeres line up on equatorial plate | (same as metaphase of mitosis?)
97
Anaphase II
Centromeres divide The division splits the replicated chromosomes
98
Telophase II
either one or both cytoplasmic divisions will occur at this time
99
The second meiotic division is \_\_\_\_\_\_\_
AN EQUATIONAL DIVISION
100
Identify the Image
Primary spermatocytes Secondary Spermatocytes Spermatids
101
Identify the Image
Cyst
102
Identify the Image
Spermatogonia
103
Identify the Image
Primary Spermatogonia Secondary Spermatogonia
104
Identify the Image
Spermatid
105
Identify the Image
Mature Sperm
106
Identify the Image Across the top left to right Across bottom left to right
Primary spermatocytes cyst spermatids spermatozoa spermatogonia secondary spermatocytes
107
Identify the Image top to bottom
Vas deferens Epididymis Testis Seminiferous tubule
108
Identify the Image
Cross Section of Seminferous tubule
109
Identify the Image across the top (left to right), down the side, across the bottom (right to left)
Sertoli cell Type B spermatogonium Type A2 spermatogonium Type A1 spermatogonium Primary speratocyte Secondary spermatocyte Spermatids Sperm Residual Body
110
Identify the Image Top, down the left side, up the right side, center
Stratum granulosa Theca interna Corona radiata Theca externa Primary ooctye culumus oophorous antrum filled with liquor folliculi
111
Identify the Image Left, bottom, right
Acrosome Nucleus Flagella
112
Identify the Image left top to bottom, right side top to bottom
Egg nests Germinal epithelium oocyte granulosa cells intermediate follicle primary follicle
113
Identify the Image
Primary Follicle primary oocyte granulosa cells
114
Identify the Image
Theca cells Granulosa cells Primary ooctye intermediate follicle
115
Identify the Image down the right side, top center, center, left, bottom corner
Theca interna zona pellucida theca externa antrum primary oocyte granulosa cells Graffian follicle
116
Identify the Image left, right
seminiferous tubule Leydig cells
117
Identify the Image down the left side, down the right side
Spermatid Spermatozoa secondary spermatocyte spermatogonia primary spermatocyte
118
Identify the Image down the left, down the right
Spermatid spermatozoa sertoli cell primary speratocyte secondary spermatocyte spermatogoina
119
Identify the Image Down the left side, right
primary follicle stratum granulosa intermediate follicle antrum with liquor folliculi zona pellucida theca follicula corona radiata cumulus oophorous egg nests
120
Identify the Image top, then counterclockwise
Sertoli cells primary speratocyte spermatozoa spermatid interstitial cell spermatogonia
121
Cyst
a cohort of presumptive germ cells in exactly the same stage of development
122
Testicular lobe
Testes are comprised of multiple lobes Development occurs form the apical to the basal region
123
The term primary spermatocytes applies to all presumptive gametes in the testis which have grown to be ____ and have _____ staining nuclei than the spermatogonia
Larger Darker
124
Nebenkern Definition and what it is found in
A dark condensation in the cytoplasm containing the mitochondria Found in spermatids
125
A short filamentous tail will be seen protruding from the spermatid even in the earliest stages of \_\_\_\_\_\_\_\_ This filament represents the ____ filament of the tail of the future \_\_\_\_\_\_\_
Spermiogenesis Axial filament Spermatozoan
126
The chromosomes cannot be identified in the nucleus by any staining procedure of the ___________ because they are so densely packed
Spermatozoan
127
Sertoli Cells
Recognized by large, dark nuclei and clear cytoplasm Provide physical support, mediate movement of steroids, restricts movement of macromolecules, phagocytose degenerating spermatogenic cells
128
Interstitial Cell of Leydig Location and funciton
Located between seminiferous tubules Produce testosterone
129
Stroma general location what is it
Bulk of the ovary = stroma connective and interstitial tissue with blood vessels
130
Egg Nests
Clusters of oogonia Located just inside the germinal epithelium (no granulosa cells yet)
131
Theca differentiate into what two layers?
Theca Interna Theca Externa
132
Antrum
Fluid-filled spaces which unite to form a cavity
133
Graafian Follicle
Mature follicle Antrum filled with liquor folliculi Nearly ready to rupture and release egg
134
Zona pellucida What is it? What does it consist of?
Non-cellular, secreted layer surrounding the primary oocyte within the graffian follicle Consists of mucopolysaccharide and typsin-digestible material
135
Corona Radiata
The stalk the oocyte rests upon
136
Cumulus oophorus
made up of follicle cells within the antrum
137
Corpus luteum What is it? Function?
Follicle cells and theca cells that remain in the ovary after ovulation Primarily produces the hormone progesterone
138
Mammalian oocytes have relatively small amounts of yolk that are uniformly distributed, while avian oocytes have an abundant store of yolk causing the nucleus to be displaced peripherally
True
139
What does corpus letuem mean in latin?
Yellow Body
140
corpus albicans What is it? Latin for what?
Inactive fibrous tissue that forms after involution of the corpus luteum white body (cells lyse = empty looking vesicle)
141
Atretic follicles
Degenerating follicles degeneration may occur at any stang
142
Identify the Image Top, under top, left, right
Male pronucleus chorion first polar body dyad
143
Identify the Image Top left, counterclockwise
Fertilization envelope chorion perivitelline space male pronucleus 2nd polar body 1st polar body
144
Identify the Image
Ascaris sperm
145
Identify the Image
Ascaris fertilization sperm penetration
146
Identify the Image right, left, bottom
Male pronucleus tetrad chorion
147
Identify the Image
A. Sperm is bond to the surface of the egg B. Sperm has entered into the egg as the fertilization cone forms while the tail still remains outside of the egg C. The sperm has entered the egg cytoplasm and the fertilization cone has closed around the sperm
148
Identify the Image
Germinal Vesicle Immature oocyte
149
Identify the Image
Mature egg
150
Identify the Image
Development of the acrosomal filament
151
Identify the Image
Fertilization envelope Female pronucleus
152
Identify the Image Top to bottom
Flagellum acrosome nucleus mitochondria
153
Identify the Image
Bound sperm x2
154
Identify the Image
TEM Bound sperm arrow points to acrosomal filament contacting egg surface Microvilli (back arrow) are found on the egg surface
155
Identify the Image
DIC unfertilized zebra mussel egg uniform in appearance, little yolk, clear cytoplasm
156
Identify the Image
Fluorescent Microscopy Unfertilized zebra mussel egg DNA-specific blue dye Egg is arrested in metaphase I
157
Identify the Image
Phase micrograph sperm inside the egg cytoplasm
158
Identify the Image
Fluorescent micrograph actin-specific dye Fertilization cone at site of sperm entry
159
Identify the Image
Phase contrast micrograph Fertilized zebra mussel egg 1st polar body
160
Identify the Image
Fluorescent Micrograph Fertilized Zebra Mussel Egg 1st polar body female DNA sperm DNA
161
Identify the Image
Phase contrast micrograph Fertilized zebra mussel egg 1st polar body 2nd polar body
162
Identify the image
Fluorescent micrograph fertilized zebra mussel egg 1st polar body 2nd polar body (doesn't shine as bright because it has half the DNA as the 1st)
163
Identify the Image Left to right
Series showing the migration of the male pronucleus toward the female pronucleus Polar bodies
164
Identify the Image
Acrosome Nucleus Mitochondria Flagellum Acrosomal Filament
165
7 steps of fertilization
1. Activation of Sperm (capacitation) 2. Penetration of sperm through jelly or cumulus layer 3. Fusion of sperm and egg 4. Establishment of blocks against entry of additional sperm 5. Completion of meiosis 6. Entry of sperm into egg cytoplasm 7. Metabolic activation of egg
166
Fertilization cone
A collection of microfilaments that form at the spot of sperm entry result in a protrusion on the egg surface
167
Fertilization envelope
Prior to fertilizaation = thin extracellular coat = vitelline envelop Following fertilization = realease of cortical granuals = vitelline envelop is elevated from egg = fertilization envelope
168
Pronuclear membrane
Once sperm enter into the cytoplasm, the sperm DNA decondensed and a new membrane forms around the DNA
169
Chorion
The thicker fertilization envelope Space is filled with a fluid (probably derived from the oocyte)
170
Dyad
one of a pair of chromosomes resulting from the separation of two homologous members of a tetrad
171
Identify the Image Center title, left top to bottom, right image top to bottom
Neurulation Neural fold Neural groove Neural ridge archenteron coelom Early neurola Neural tube archenteron late neurula
172
Identify the Image Top, couterclockwise
Animal pole frog 2-cell stage vegetal pole blastomeres 1st cleavage plane
173
Identify the Image
Micromeres Macromeres
174
Identify the Image Left most, clockwise
Animal pole Vegetal pole Late blastula Macromeres Micromeres Blastocoel
175
Identify the Image top to bottom
Animal pole micromeres blastocoel marcromeres vegetal pole
176
Identify the Image Top left, counterclockwise
~Early Frog Gastrula~ animal hemisphere vegetal hemisphere dorsal lip of the blastopore macromeres micromeres blastocoel
177
Identify the Image Top to bottom
~Early Frog Grastula~ Animal pole blastocoel micromere dorsal blastoporal lip macromere vegetal pole
178
Identify the Image Left, top, right
Follicle cells Supernumerary nucleoli Lampbrush chromosome
179
Identify the Image Left most, counterclockwise
Animal pole vegetal pole blastocoel yolk plug dorsal lip of blastopore archenteron
180
Identify the Image left most, counterclockwise
Animal pole blastocoel macromere dorsal blastoporal lip micromere archenteron
181
Identify the Image
Frog Ovary (ready to ovulate) Oocyte
182
Identify the Image Top left, left to right
Frog Ovary Oocyte germinal vesicle follicle cells
183
Identify the Image top, left to right
Frog Ovary (maturing) older oocytes young oocytes
184
Identify the Image
Blastomere Cleavage
185
Identify the Image left, right
Blastomeres Fertilization Envelope
186
Identify the Image top, bottom, left, right
Blastomeres Blastocoel Early Blastula Later Blastula
187
Identify the Image top left, down the right side, bottom left
Blastocoel Blastopore Archenteron Blastomeres
188
Identify the Image
Blastomeres
189
Identify the Image left, right, bottom
Germinal Vesicle Nucleolus Starfish Oocyte
190
Identify the Image top to bottom
Fertilization envelope Perivitelline Space Female pronucleus
191
Blastulation
After several cleavages a cavity forms in the center of a dividing ball
192
Following blastulation, an _________ of peripheral cells creates a second cavity, the \_\_\_\_\_\_\_\_\_\_\_
Invagination Archenteron
193
Gastrulation
The process of invagination
194
Blastocoel
Central cavity formed during blastulation
195
Morula
A solid ball of cells formed after multiple divisions
196
Blastopore
The opening to the archenteron
197
Perivitelline space
The separation between the egg surface and the fertilization envelope
198
Zygote
Fertilized egg prior to cleavage
199
Mesolecithal
Eggs with relatively large quantity of yolk ex. Amphibian eggs
200
Oolemma
Egg plasma membrane
201
Grey Crescent
Sperm entry causes the outer cytoplasm of the animal hemisphere to shift 30 degrees downward on the side where sperm binding occured The shift exposes a portion of the underlying cytoplasm on the side opposite of sperm binding This exposed cytoplasm is termed the grey crescent
202
Holoblastic
having cleavage planes that divide the egg into separate blastomeres
203
Meridional
When a furrow bisect both the poles of the egg passing through the median axis or centre of egg
204
Vegetal Hemisphere
The side of the egg with the displaced yolk
205
Animal Hemisphere
The part of the egg that does not contain the yolk
206
Dorsal Blastoporal Lip
Site of involution
207
Yolk Plug
A region between the blastoporal lips of stationary, underlying cell not involved in the involution
208
Neural plate
Thickened dorsal tissue
209
Neural fold
The neural plate folded into a V-shape
210
Neural ridges
the upraised portions of the neural fold
211
Neural groove
The central depression in the neural fold