Quiz 3 lecture 1 Part 2 Flashcards
What is cyclomorphosis?
Is the systematic change in a body form through successive generations over a season and is observed in rotifers and cladocerans
Why does cyclomorphosis occur?
This happens because they wanna avoid predation
Given an example of cyclomorphosis?
Branchonius rotifer put two together Br was doing better, then bigger species of rotifor that’s predator was added Asplanchia, then Br drops as predator goes up, predator goes down, and then second BC increases, this is due to Bc developed spine lengths so predator didnt want to eat it
How does pathogenesis occur?
In favourable conditions: short asexual life cycles, a high allocation of energy goes to egg production but unfavourable condtions (change in temp, low water level, low nutrients) does sexual reproduction and produces resting eggs.
IN unfavourbale parthenogenic son is produced mating occurs, haploid eggs formed used as resting eggs, stay in substrate and come back with good conditions.
How and why does vertical migration happen?
In situations throughout the day zooplankton migrate, during the night they will be closer to the surface and during the day will be lower down to avoid getting eaten when predators can see them, but they avoid food as well in the photic zone.
How does zooplankton size matter?
larger zooplankton filter more efficiently and can eat larger particles, but they are more easily captured by planktivouros fish
What is zooplanktons role in clear water phase?
In january febuary have it iced over, in march and april mixing occurs and nutrients from mixing goes in, phytoplankton picks it and grows really fast early spring, then zooplankton increase by eating, then phytoplankton get consumed and have no nutrients, now stratification happens and water is run out nutrients, then nutrients will vary and see blips of increase as mixing occurs again
What are the four major groups of macrophytes?
Macrophytic algae
2. Mosses
3. Fern allies
4. Angiosperms
What is the distribution of macrophytes related to?
light- anything that does photosynthesis will compete to be at top so they shade everything else
substrate- is there something there they can actually root to
nutrients- having roots in sediment in which they are a lot of nutrients so being roote dis an adavantage
4- ability to deal with water movement: lets you stay in place- in big moving water no macrophytes as roots not strong enough.
5. Temperature
Near shore what do we see? deeper?
emergent rooted macrophytes, floating, submerged - trade off betwene ability to compete and cost of growing structures, hard to grow all the way up
How is reproduction adapted in macrophytes?
pollination a challenge, if your emerging or a floating plant you might be able to have pollen on top of water and get into wind- spread out pollination.
Animal pollinators, something passes by and touches it
Asexual reproduction- will allow clones to establish themselves
How is gas transport work in macrophytes?
heterophylly- change in shape/structure of leaves between under water and above water, below water see finer dissected structure because water holds up. because strong leaves will gas exchnage at top
arenchyma- air channels will move gases from air inot water- is pongy linking tissues
What are macrophyte contributions to productivity?
emergent macrophytes contrbute a lot to productivity, also uptake nutrients in sediment bring them inot structures and then water column, they can also effect sediment trapping they will slow down flow and then capture nutrients and put into sediments , also accelerate sedimentation and ther enutriention being locked in, periphyton (phyta that live n things) will live in this plants, allelopathy- is the inhibition of competing organisms through excreted chemicals this limits how other plants around them will be able to surivive, competing organisms is usually phytoplankton- some macrophytes excrete chemical compounds that limit success of phytoplankton
