University:
York University
Course:
SC/BIOL 2021 | Cell Biology
Academic year:

2019
Views:

261

Pages:

2
Author:

Nick T.

Section 1: Transfer efficiency can be from 10-60%. Fish abundance can be controlled by bottom-up or top-down controls. Bottom-up: phytoplankton affecting abundance of fish. Top-down: amount of commercial/anglers fishing. Section 2: There are few "pure" bottom-up/top-down scenarios. Commercial fishing reduces biomass and body size of fish. P/B goes up (production goes down, but not as much as biomass). Section 3: Eutrophication: sending stuff into the ocean to ramp up primary production. If not kept in check, could make water hypoxic (low O₂). Mild hypoxia drives benthic invertebrates to leave their spot and get eaten. Anoxic means no oxygen. Severe hypoxia leads to anoxia. Climate affects primary production and ultimately secondary production. Section 4: How to calculate secondary production: N: number of individuals Avg B: average biomass Δ Avg B: change in average biomass Avg N: average number of individuals Avg N*A: average number of individuals times average age Section 1: Notes From SG Thermally Stratified: warm, rapid drop in temperature Standard average: 35 ppt (small deviations) Halocline: changes in salinity Biotic and abiotic factors control distribution of a species Section 2: Ocean's 4 biomes: Trades, Westerlies, Polar, Coastal Rivet and Redundancy Hypothesis: Poor diversity = critical ecosystem Zonation: Areas of dividing diversity/richness Competition can increase diversification Success can be measured by ADE (Abundance, Diversity, Evolution of complexity) Being big has its drawbacks Section 3: Primary Producers: Macroalgae, microalgae, Seagrasses, phytoplankton Forms of inorganic carbon: CO₂, CO₃, HCO₃ Light penetrates ~200 m in clear water Accessory pigments are important sometimes Growth Yield = G / (G + E + R) Trophic yield = (n + 1) / n