Banca de DEFESA: VIVIAN VASCONCELLOS SOARES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : VIVIAN VASCONCELLOS SOARES
DATA : 31/10/2019
HORA: 09:00
LOCAL: Salão Nobre do Instituto de Biologia da UFBA
TÍTULO:

Influence of the evolution and ecology in the reproduction of Porifera

PALAVRAS-CHAVES:

Ultrastructure, gametes; larvae;multimodel

PÁGINAS: 150
GRANDE ÁREA: Ciências Biológicas
ÁREA: Zoologia
SUBÁREA: Morfologia dos Grupos Recentes
RESUMO:

Sponges are simple animals; they have no tissue or organs. The body plan of sponges are directly related to the aquiferous system, where the main physiological activities are performed. As sponges do not have gonads, some somatic cells change to give rise to sperm and oocytes. The ultrastructural morphology of sperm and oocytes is influenced not only by the phylogenetic position of the species, but also by the physiological conditions and functional demands during gamete dispersion and subsequent fertilization processes. However, in sponges, both the physiological conditions and phylogenetic relationships of various sperm and oocyte morphologies remain poorly understood. Fertilization results in an embryo that develops into a larval form. Depending on cleavage patterns, morphogenesis and larval morphology, embryonic development in Porifera can be classified into eight characteristic types of different evolutionary lineages. The parenchymella larvae is considered the most complex since its organization and its cell types may vary within genus. However, cell types and their functions in the development process are not yet well understood. Another aspect that should be studied in Porifera is asexual reproduction, which is an important strategy for sponges, as it can compensate for the fact that gametes are released into the water column. The reproductive period (asexual and sexual) of sponges has no clear pattern. Knowing reproductive strategies and dynamics is important for understanding population dynamics, biogeography and species continuity, as the ecological dynamics of many marine species are affected by their life histories. Thus, this thesis aims to investigate the ultrastructure of reproductive elements and reproductive dynamics in different Porifera strains in order to understand their evolutionary and ecological implications. As specific objectives, we will: (1) compare the spermatogenesis of Tedania ignis, Iphon piceus and Iophon proximum Poecilosclerida order; (2) compare the ovogenesis of Cinachyrella apion and Tethya maza; (3) compare cell types and structure of parenchymal larvae Amphimedon queenslandica and Tedania ignis; (4) understand the influence of environmental factors in the intertidal region on the asexual and sexual reproduction of Cinachyrella apion and Tethya maza

MEMBROS DA BANCA:
Presidente - 1914176 - EMILIO DE LANNA NETO
Interno - 033.068.485-06 - ANA CAROLINA SOUSA DE ALMEIDA - UFPE
Interno - 2130445 - FERNANDA FERNANDES CAVALCANTI
Externo ao Programa - 3143542 - JANAINA LIMA DE OLIVEIRA
Externo à Instituição - MICHELLE REGINA LEMOS KLAUTAU - UFRJ