Presentations

Reproduction & Development in Hypo- and Hypergravity

Source: Universities Space Research Association   Format: PDF
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Description: This document from a short course on basic biology for engineers was developed to provide a better understanding on the effects of altered gravity on reproduction and development and features experiment results from Medaka fish and rats. (Posted on 10/04)

Vertebrate Development

Source: Ronald D. Reed, United States Air Force Academy   Format: Microsoft PowerPoint
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Description: This presentation presents the developmental changes that vertebrates undergo and how they are affected by the microgravity environment. (Posted on 10/00)

Developmental Biology

Source: Ronald D. Reed, United States Air Force Academy  Format: Microsoft PowerPoint
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Description: This presentation explains the role of gravity in basic developmental biology. The potential for human pregnancy and birth in space is also evaluated. (Posted on 10/00)

Still Images

Frog Egg Development
Source: NASA
Format: JPEG
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Description: Frog eggs are spawned in a random orientation with regard to gravity (left). Like most amphibian eggs, these eggs from the African Clawed Frog, Xenopus laevis, are darkly pigmented in one hemisphere and lightly pigmented in the other. Within minutes after fertilization, the eggs rotate in their gelatinous capsules, such that the darkly pigmented hemispheres face up. (Posted on 10/00)

Frog Life Cycle
Source: NASA
Format: JPEG
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Description: Fertilization of a Xenopus egg is followed by cleavage (a succession of cell divisions that partition the large fertilized egg cell in smaller cells), differentiation and organogenesis. After hatching from the egg, the tadpole will exist in an aquatic stage with gills and a tail, until complex hormonal changes transform it into an adult frog. (Posted on 08/03)

Jellyfish Development Cycle
Source: NASA
Format: JPEG
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Description: Aurelia aurita, the moon jellyfish, undergoes both asexual and sexual reproduction during its life cycle. Sessile polyps metamorphose into strobilae, which produce ephyrae by asexual budding. The ephyrae mature into medusae, which produce zygotes and reproduce sexually. Planula larvae that hatch from fertilized eggs eventually attach to a new substrate and develop into polyps. (Posted on 08/03)