Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638002
Title: Studies on feeding in Bryozoa
Author: Markham, J. B.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1988
Availability of Full Text:
Access from EThOS:
Abstract:
Procedures to reduce errors in Coulter analyses - In counts of suspensions of algae and inert particles made with a negative external electrode (EE), neither total number of particles per unit volume of suspension nor mean cell or particle volume (MCV) ever changed. In contrast, a count made with a positive EE exhibited a substantial change in MCV. A review of published investigations of damage to red blood corpuscles caused by a count suggests that they are affected in a similar way. Function of the gizzard in Bryozoa - Five gizzard-bearers frequently displayed significantly greater ability to break diatom frustules, when compared with two other bryozoans. The species lacking a gizzard have good ability to separate valves of some diatoms frustules, even to the extent of equalling the percentage broken by the gizzard of Bowerbankia. However, bryozoans that possess a gizzard are small, too small to ingest a majority of the common diatoms. Selection of food by two marine bryozoans - The preferences of Electra pilosa and Flustrellidra hispida have been investigated. E. pilosa, offered mixtures of algae and pollen, did not distinguish between pollen and algal cells but preferentially selected foods of 15-40 um diameter. E. pilosa appears able to select particles with regard to size but not taste, and preferences are affected by total but not relative food concentration. E. pilosa and F. hispida have lophophores of greatly different size, but preferentially selected similar size categories from seston. These were those sizes most abundant in local seawater samples. Optimal design of the bryozoan lophophore - The lateral cilia of Flustrellidra hispida close the intertentacular gap over the proximal 30%, or less, of the length of the gap. A method was developed to study optimal design, and used to determine which characteristics of funnel morphology are optimized by natural selection.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.638002  DOI: Not available
Share: