Taxonomy and Ecology

Basically this is what I need to know about taxonomy:

Taxonomy is the naming and classifying of organisms. A taxon is a group of organisms in a classification system.
 
Key concept:
The current tree of life has three domains (Bacteria, Archaea, Eukarya)
 
- All living things bear scientific names that use the binomial signature (two parts, reflecting its genus and species)
- Linnaeus Classification System: Seven levels (need to remember all seven: Kingdom, Phylum, Class, Order, Family, Genus, Species)
- Linnaeus taxonomy does not account for molecular evidence
- Interpret data given from this classification system
- There are six kingdoms (Animalia, Plantae, Protista, Archaea, Bacteria, Fungi) and preceding that, 3 domains
- Domain Bacteria branches into the Bacteria kingdom
- Domain Archaea branches into the Archaeal kingdom
- Domain Eukarya (all eukaryotes) branches into the Protista, Animalia, Plantae and Fungi kingdoms
- Classification of living things is a work in progress.
 
And a little bit on ecology:

- Living things cannot exist alone, there must be a relationship between them.

- Living things are adapted to the environment where they live.
- Ecology is the study of how living things interact with each other and with their environment.
- Abiotic factors (light, temperature, water) & biotic factors (organisms)

Microscopy Notes

Today we learnt about microscopes.

Parts of a microscope:
Arm: Supports the body tube and is the part that you can grasp to carry the microscope. Pick up your microscope by its arm, keeping it upright, and supporting it underneath with your free hand. Set it gently on your lab desk.
Base: Gives the microscope a firm, steady support.
Ocular lens (Eye piece): Magnifies ten times (l0x). This lens is often unattached, and thus it may fall out unless the microscope is kept upright.
Objective Lens: Magnifies the object by the factor marked on the particular lens. Low power (l0x) gives the smallest image, high power gives a large image (40x), and oil immersion gives the largest image (l00x). Sometimes a very low power scan objective (4x) replaces the oil immersion lens. *Objective lenses are always used in order: low, high, oil immersion.
Nosepiece: The revolving part to which objectives are attached. It must be firmly clicked into position when the objective is changed. Rough treatment can cause it to snap off.
Body tube: Joins the nosepiece to the ocular lens.
Stage: Supports the slide that is held onto it by stage clip, and has a hole so that light can shine up through the specimen. Always centre the specimen over this hole.
Coarse adjustment: Moves the body tube or stage up and down, depending on the design of the microscope, to approximately the right position so that the specimen is in focus. This knob is used only with the low power.
Fine adjustment: Moves the body tube (or stage) up and down to precisely the right position so that the specimen is perfectly in focus. Use it to achieve fine focus with the low power objective and for all focusing with the high power and oil immersion objectives.
Light source: Usually a small electric light beneath the stage that is controlled by a push-button light switch. Sometimes a mirror is used to reflect light from another source into the microscope.
Iris diaphragm: Regulates how much light goes through the specimen. It is controlled by a lever that is moved back and forth.
Condenser: A lens located above the diaphragm which concentrates the light before it passes through the specimen. Its position is controlled by a knob on microscopes in which it is adjustable
Letter 'e' magnified:

 

http://www.fossweb.com/delegate/ssi-foss-ucm/Contribution%20Folders/FOSS/multimedia_ms_1E/DiversityofLife/media/microscope.htm

http://www.udel.edu/biology/ketcham/microscope/scope.html

What Is Life? Characteristics of Living Things

Characteristics of living things:
1. Responds to stimuli
2. Requires nutrition*

*Nutrition: 4 stages:
Feeding (putting food in mouth)
Digestion - Physical (chewing/mastication), Chemical (enzymes)
                 - Purpose: To break food into simple, diffusible forms
Absorption (absorbing these simple, diffusible forms)
Assimilation (making use of these simple, diffusible forms)
--> There are 3 forms of carbohydrates:
Monosaccharides (e.g. glucose, basic forms which our bodies can absorb)
Disaccharides
Polysaccharides (e.g.cellulose, glycogen (a storage form of carbohydrates), starch (storage in plants only)

3. Requires oxygen - so that they can respire**
(exception: anaerobic life forms!)

**Respiration: 2 types:
Aerobic
- Process: glucose + oxygen --> respiration--> energy + water + carbon dioxide
Anaerobic (in the absence)
- Process: glucose --> respiration --> energy + alcohol + carbon dioxide
(the above process is alcoholic fermentation in plants - replace glucose with grapes for wine and wheat for beer)
- Creatures that use this form of respiration: yeast, microscopic lifeforms in deep sea vents, volcanos
- We use anaerobic respiration with aerobic respiration when running
(the process for this is the same except alcohol is replaced with lactic acid. This is stored in our muscles and causes muscle cramps when its maximum level is reached. It makes you gasp for oxygen to break down the lactic acid)

4. Requires water
5. Grows
6. Dies eventually - life cycle
7. Produces waste

Criteria for Living Things

What is Life?
Group discussion on the defining criteria of living things

S/N	Criteria (for a living thing)	How Would You Test this Criteria	Challenges
1	Requires Oxygen	Place it in a controlled environment. Wait. Measure the composition of the air (less oxygen, more carbon dioxide/water vapour)	It could chemically react with components in the air, not due to respiration.
2	Responds to Stimuli	Introduce changes in its environment (light/dark, temperature changes, sound, other organisms)	Its response may be unnoticeable. It may not respond to such changes in environment.
3	Requires Nutrition	Observe it in its natural environment. See if it consumes food/water.	It may not need much nutrition at the time or all the time. It may not consume food but instead produce energy (plants).
4	Has Cells	Use a microscope to test if it has cells.	It might be a single-celled organism.