Amphibians and Fish: Early Development and Axis Formation

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Amphibians and Fish Early Development and Axis
Formation

• BIOL 370 Developmental Biology
• Chapter 7b
• (Chapter 8 in the textbook)
• Lange

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Standardized Color Scheme Ectoderm outer germ
layer will become nervous system, tooth
enamel, epidermis, lining of the mouth, anus,
nostrils, sweat glands, hair and nails. Mesoderm
middle germ layer will become the muscle
(smooth, cardiac and skeletal), connective
tissues, dermis, hypodermis (subcutaneous layer
of the skin), bone, cartilage, red blood cells,
white blood cells, kidneys, and the adrenal
cortex. Endoderm inner germ layer will
become a variety of epithelia including the
alimentary canal (excluding specialized parts of
the mouth, pharynx rectum), the lining cells of
all the glands, trachea, bronchi, and alveoli of
the lungs, endocrine glands, auditory tube,
urinary bladder and parts of the urethra.
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Figure 7.23 Vegetal induction of mesoderm
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Figure 7.23 Vegetal induction of mesoderm (Part
1)
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Figure 7.23 Vegetal induction of mesoderm (Part
2)
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Figure 7.25 The soluble protein Noggin
dorsalizes the amphibian embryo
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Figure 7.27 Model for the action of the organizer
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Figure 7.29 Regional and temporal specificity of
induction
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Figure 7.30 Paracrine factor antagonists from
the organizer are able to block specific
paracrine factors to distinguish head from tail
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Figure 7.30 Paracrine factor antagonists from
the organizer are able to block specific
paracrine factors to distinguish head from tail
(Part 1)
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Figure 7.30 Paracrine factor antagonists from
the organizer are able to block specific
paracrine factors to distinguish head from tail
(Part 2)
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Figure 7.31 Cerberus mRNA injected into a single
D4 blastomere of a 32-cell Xenopus embryo induces
head structures as well as a duplicated heart and
liver
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Figure 7.33 Insulin-like growth factors enhance
anterior neural development
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Figure 7.35 Model of organizer function and axis
specification in the Xenopus gastrula
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Figure 7.36 Pitx2 determines the direction of
heart looping and gut coiling
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Figure 7.37 Zebrafish development occurs very
rapidly
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Figure 7.37 Zebrafish development occurs very
rapidly (Part 1)
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Figure 7.37 Zebrafish development occurs very
rapidly (Part 2)
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Figure 7.38 Screening protocol for identifying
mutations of zebrafish development
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Figure 7.38 Screening protocol for identifying
mutations of zebrafish development (Part 1)
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Figure 7.38 Screening protocol for identifying
mutations of zebrafish development (Part 2)
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Figure 7.39 The gene for green fluorescent
protein was fused to the regulatory region of a
zebrafish sonic hedgehog gene
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Figure 7.40 Discoidal meroblastic cleavage in a
zebrafish egg
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Figure 7.41 Fish blastula
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Figure 7.41 Fish blastula (Part 1)
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Figure 7.41 Fish blastula (Part 2)
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