Coralline red algae are highly abunadant and well diversified in the well exposed carbonate deposits of the Lower Pliocene Shagra Formation at Wadi Wizer, Red Sea coast, Egypt. Lithostratigraphically, the Shagra Formation unconformably overlies the Late Miocene Marsa Alam Formation and underlies the Quaternary deposits. This carbonate facies is dominated by different assemblage of coralline red...

1. Blue-green algae, red algae, and purple bacteria all show the emission of delayed light. 2. The action spectra for the production of delayed light by three species of blue-green algae have one broad band with a peak at 620 mmicro. 3. The action spectrum for production of delayed light by the red algae has one peak at 550 mmicro with a shoulder from 600 to 660 mmicro. 4. The emission spectra ...

Tropical coastal marine ecosystems including mangroves, seagrass beds and coral reef communities are undergoing intense degradation in response to natural and human disturbances, therefore, understanding the causes and mechanisms present challenges for scientist and managers. In order to protect our marine resources, determining the effects of nutrient loads on these coastal systems has become ...

Psychrophilic algae blooms can be observed coloring the snow during the melt season in alpine snowfields. These algae are important primary producers on the snow surface environment, supporting the microbial community that coexists with algae, which includes heterotrophic bacteria and fungi. In this study, we analyzed the microbial community of green and red-colored snow containing algae from M...

Individual variation in habitat use has important ecological and evolutionary consequences. Here, we combine developmental and functional approaches to study habitat use in Pugettia producta, a marine crab that sequesters pigments from the algae it inhabits and consumes to camouflage with different colored algal habitats. Pugettia from different habitats differ in size and color; individuals li...

A polarographic oxygen determination, with tissue in direct contact with a stationary platinum electrode, has been used to measure the photosynthetic response of marine algae. These were exposed to monochromatic light, of equal energy, at some 35 points through the visible spectrum (derived from a monochromator). Ulva and Monostroma (green algae) show action spectra which correspond very closel...

A phylogenetic tree of most of the major groups of organisms has been constructed from the 352 5S ribosomal RNA sequences now available. The tree suggests that there are several major groups of eubacteria that diverged during the early stages of their evolution. Metabacteria (= archaebacteria) and eukaryotes separated after the emergence of eubacteria. Among eukaryotes, red algae emerged first;...

Using the large subunit of RuBisCo (rbcL) sequences from cyanobacteria, proteobacteria, and diverse groups of algae and green plants, we evaluated the plastid relationship between haptophytes and heterokont algae. The rbcL sequences were determined from three taxa of heterokont algae (Bumilleriopsis filiformis, Pelagomonas calceolata, and Pseudopedinella elastica) and added to 25 published sequ...

in this study antioxidant activity of the red algae (hypnea hamulosa) was investigated in the invitro condition. the measurement included total phenolic content, ferric reducing power, dpph radical scavenging activity and total antioxidant activity. seaweed samples with the ratio of 1:20 (algae: solvent) were extracted using conventional solvent extraction method for 24 hours. the applied solve...

The identification of marine algae in the Sistan and Baluchestan Province were performed from December 1998 to November 1999 at the coastal area of Gwatr (25 10´ N; 61 30´ E) and Mydani (25 24´ N; 59 5´ E). Data on vegetation were gathered in subtidal and intertidal zones by seasonal and monthly sampling, respectively. Samples were transferred to the laboratory and fixed in 4% formalin. Accordi...