Accession Number:

ADA393406

Title:

Diel Variations in Optical Properties of Micromonas pusilla, A prasinophyte

Descriptive Note:

Technical rept.

Corporate Author:

WOODS HOLE OCEANOGRAPHIC INSTITUTION MA

Report Date:

2001-08-24

Pagination or Media Count:

12.0

Abstract:

A laboratory experiment was conducted on cultures of Micromonas pusilla, a marine prasinophyte, to investigate how cell growth and division affect the optical properties over the lightdark cycle. Measurements were made of cell size and concentration, attenuation and absorption coefficients, flow cytometric light scattering in forward and side directions, chlorophyll and carbon content. Refractive index was calculated using the anomalous diffraction approximation Cells were about 1.5 micrometers in diameter and exhibited phased division, with the major division burst occurring during the night. Typical diel variations were observed, with cells increasing in size and light scattering during the day as they photosynthesize and decreasing at night upon division. The cells were in ultradian growth, with more than one division per day, at a light level of 120 Mu-mol photons msqsec. Since these cells are similar in size to small phytoplankton that are typically abundant in field samples, these results can be used in the interpretation of diel variations in light scattering in natural populations of phytoplankton.

Subject Categories:

  • Biochemistry
  • Microbiology
  • Organic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE