L-1-Introduction, taxonomy (1) (3)

The biological levels of organization of living things
From a single organelle to the entire biosphere, living organisms are parts of a highly structured hierarchy

The Biosphere
The most complex level of organization
composed of
Populations: all members of one species in one area
Communities: the populations of various organisms in an area
Ecosystem: the communities interacting with their physical environment

4.Acquisition of Materials and Energy
Organisms need nutrients and energy to live through food
Nutrients, the building blocks of cells;
Energy, the capacity to do work, our fuel;
Metabolism: all chemical reactions that occur in a cell;
Photosynthesis: plant process that transforms solar energy into chemical used by organisms.
Producers, Consumers, and Decomposers in the Forest Community.

Producers
A: Producers: Photosynthesizing organisms
Producers are any kind of green plant.
Green plants make their food by taking sunlight and using the energy to make sugar.
The plant uses this sugar, also called glucose to make many things, such as wood, leaves, roots, and bark.

Figure: Living things acquire materials and energy through food and they reproduce
Cannot make their own food.
They get energy and nutrients by feeding on other organisms.
Animals are consumers
Consumers

Taxonomy
The discipline of identifying and classifying organisms according to their evolutionary history and relationships.
Organisms are grouped together into taxa (singular: taxon) and these groups are given a taxonomic rank.
Levels of classification (specific to general):
Species (вид),
Genus (род),
Family (семейство),
Order (Ряд),
Class (класс),
Phylum (тип),
Kingdom (царство),
Domain (надцарство)

Table 1.4 Levels of Classification

Domain
In Nature we find Three domains:
Bacteria
Archea
Eukarya
Bacteria and Archaea are prokaryotes single cell organism in which the DNA is not contained in a nucleus
Eukarya are eukaryotes and have membrane-bound nucleus

Figure. Domain Archaea: Methanosarcina mazei, an archaeon

Figure. Domain Bacteria: Escherichia coli, a bacterium.

Four Steps of the Scientific Methods
Observation: what scientists can sense in the world around them
Hypothesis: a proposed explanation for an observation of how a natural process works.
Testing: using either observation or experimentation to disprove a hypothesis
Conclusion: the results are analyzed and the hypothesis is supported or rejected