Practical 1 Flashcards
Kingdom Protista
Group of eukaryotic organisms that cannot be classified in any of the other kingdom (fungi, monera, animal, or plant).
Protists always require ______, which ___________.
moisture
restricts them to a narrow range of environmental conditions
Eukaryotes
Organisms whose cells are organized into complex structures, membrane bound nucleus and a cytoskeleton.
Protists Feeding
Protists can be heterotrophic (eat other organisms) or autotrophic (produce their own food) or both.
How do Amoeba respire?
By exchanging gases through its semi-permeable membrane via diffusion; O2 moves into the cell while CO2 moves out.
Why are contractile vacuoles important to the Amoeba?
To regulate water balance.
How do Amoeba move if they don’t have muscle?
Their endoplasm flows inside of the wall of ectoplasm to make pseudopodia.
Microfilaments of actin and myosin are associated with these movements.
How do Amoeba feed?
The cytoplasm flows around the prey (to form a pseudopod) and engulfs it, with a drop of water, in a food vacuole and secretes enzymes into it.
Functions carried out by an Amoeba.
Reproduction
Movement
Digestion
Define:
Diffusion
The movement of molecules or particles along a concentration gradient (from higher to lower concentration).
Define (in Amoeba): Plasma membrane Ectoplasm Endoplasm Nucleus Contractile vacuole Food vacuoles
Plasma membrane – the cell surface of the Amoeba
Ectoplasm - the clear outer region of the protoplasm
Endoplasm - the inner, granular protoplasm
Nucleus - round, large and dark structure in the endoplasm
Contractile vacuole - transparent vesicle that excretes excess water and wastes
Food vacuoles - a cavity in which food is digested
How do Euglena feed?
Hint: there are two ways
Photosynthesis (autotrophic): small chloroplasts and stigma that helps them detect and move towards light.
Osmotrophy: absorb nutrients across their plasma membrane via osmotrophy when in the dark.
What are the animal characteristics of Euglena?
Gullet, flagella and food reservoir.
Paramecium are covered with minute hair-like projections called cilia used for…
Locomotion and feeding.
Do Paramecium learn from experience?
No.
Describe how Paramecium feed.
- Uses its cilia to sweep food and water through its oral grode and into its gullet
- When enough food has accumulated, a vacuole forms in the cytoplasm and then circulates in the cell
- Once digested, the vacuole ruptures at the anal pore and expels its waste into the environment
How do the shells and skeletons of Foraminifera and Radiolaria differ from one another?
Foraminifera seems to have quite robust, strong shells.
Radiolarias’ shells were generally symmetrical and free standing whereas Foraminifera was fairly random and often comprised of multiple shells stuck together.
Define:
Commensalism
Mutualism
Parasitism
Commensalism - both members benefit, but each can live independently.
Mutualism - both members benefit and are unable to live independently.
Parasitism - where one member benefits at the expense of the other.
