Animal Sciences Commons^™

A New Hypothesis Conerning The Sequence And Nature Of Meiotic Events In The Female Of Drosophila Melanogaster, Rhonda F. Grell

Doctoral Dissertations

Three of the basic phenomena comprising the meiotic process are synapsis, crossingover, and disjunction. It is generally conceded that some form of pairing must precede crossingover; that the crossingover process occurs prior to disjunction; and that disjunction implies a previous association of elements. Construction of a model describing the causal relations among the three events might be expected to be fairly simple, since the possibilities are limited. Yet, no model has been proposed that is consistent with all the genetic data.

Studies On The Morphology And Growh Rate Of The Cestode Hymenolepis Microstoma After Gamma Irradiation Of The Cysticercoids And Eggs, Huldrich H. Kuhlman

Doctoral Dissertations

From the literature on effects of radiation on mammals, insects, and other organisms, it appears that radiation produces abnormalities chiefly by destroying or inhibiting growing cells and tissues. The effects on length of the worms may be due to reduction in cell population responsible for growth. The presence of certain morphological abnormalities which have been observed, particularly those which have been characterized by the absence of one or more reproductive organs, might also be attributed to a change in the growth or embryological apparatus and that radiation only serves to increase the frequency of these disturbances.

For further similar studies …

Meiosis, Mitosis, And The Induction Of Chromosomal Abnormalities In Hymenolepis Diminuta By Gamma Rays, Raymond Louis Kisner

Doctoral Dissertations

Summary

A growth rate study for H. diminuta in ten worm infestations was attempted. The desired number of worms was not recovered from enough rats to determine a reliable growth curve. It was discovered that worm length varied within rats and between rats of comparable sex, age, weight, worm burden, and genetic background.