What is the smallest organizational unit of living things?
What are the six basic characteristics of all living things?
- 1. Organization
- 2. Metabolizm
- 3. Stimulus
- 4. Reproduction
- 5. Evolution
- 6. Homeostasis
What is the significance of the DNA molecule in terms of organization?
It is highly organized. It provides the information for the specific origanization of a given organism.
- This refers to the concept that some members of a species have a greater ability to survive than others.
- (Darwin called it the "Survival of the fittest")
Diversity of organisms
- This refers to the variation of organisms in structure and behavior.
- Living organisms are tremendously varied.
- Despite their diversity, all living organisms display the basic characteristics of life.
DNA - Deoxyribonucleic Acid
This is the hereditary molecule which provides the blueprint or recipe for the organization and structure of the organism.
- This is the change in the genetic makeup of organisms over generations.
- This is the result of genetic variation and differential survival.
- The genes for these favorable traits are passed on to the next generation
- Members of a species differ genetically from each other.
- This is largely due to sexual reproduction and mutation.
- This is the maintenance of the internal environment of an organism.
- This include maintenance of cell structure and arrangement, cell chemistry and pH.
- Cell chemistry and pH is maintained through regulation of cellular metabolism.
- In warm-blodded organisms, body temperature is maintained.
- All of the chemical reactions carried out by an organism are referred to as the organism's ___________.
- This is used to synthesize larger molecules from smaller molecules to modify molecules, to break down molecules and to convert energy.
- This is a change in the hereditary molecule DNA.
- This can change a particular hereditary characteristic of an organism.
- This occurs rarely and randomly.
- The chance of this happening can be increased by radiation and certain chemicals (mutagens).
One-celled organism (unicellular)
- Some organisms are composed of a single cell.
- Examples of these organisms are the amoeba and paramecium.
- This refers to an arrangement that is not random but is planned and precise.
- Living things are highly organized in terms of the arrangement of atoms into molecules, molecules into cells, and cells into multicellular organism.
- DNA provides the blueprint for the organization of a living organism.
This is a characteristic of a living organism that enables its survival in a particular environment.Example: Gills are an adaptation that allow fish to survive in water.
Term used to describe organisms composed of many cells.
Genetic _______ refers to the idea that members of a species differ genetically from each other.
Members of a species differ genetically from each other. This is largely due to sexual reproduction and mutation.
Organisms composed of a single cell.
- This is the process by which green plants convert light energy to chemical energy and convert inorganic carbon dioxide (CO2) to organic molecules such as sugars.
- In the process, oxygen gas (O2) is released from water.
Reproduction - Asexual
- This is a process by which an individual organism produces offspring which are gentically identical to the parent. Examples include the budding of hydra from the parent, cell division in a one-cell organism such as amoeba, and growth of a potato plant from a bud (eye) on a potato tuber.
- This can be carried out artificially by growing a plant from a cutting or by cloning as in the sheep, "Dolly".
Reproduction - Sexual
- This involves the production of an offspring that derives chromosomes from two different cells ("sex cells"). In vertebrates, the cells are the egg and sperm and come from the mother and father. In higher plants, the cells are egg and pollen that are produced in the flower and may come from the same plant or different plants. The resulting offspring are genetically different from either parent.
- Except in the case of identical twins, each offspring is genetically different from each other.
Response to stimulus
Organisms respond (react) to this (external factors such as light or temperature). This expression generally refers to activities or reactions which are carried out without conscious thought and are genetically determined. Examples include the growth of a plant toward light, or the retraction of a human hand from a hot object.
A major advantage of being multicellular is...?
- These cells can specialize.
- Different types of cells have different structures which enable them to carry out different functions.
- Cells that lack a nucleus or other specialized compartments.
- They do contain DNA and ribosomes.
- These cells are described as "PROKARYOTIC"
- (Pro=primitive, Karyotic=nucleus - primitive nucleus)
- A cell that contains a true nucleus.
- These cells have a nucleus which contains DNA, as well as many other specialized organelles or compartments.
- These cells are larger than the prokaryotic
A type of cell division which results in cells that are genetically identical to the original cells.
- This is a process of reductional division in which the number of chromosomes per cell is cut in half.
- In humans, the father's sperms has 23 chromosomes and the mother's egg has 23 chromosomes. After the egg is fertilized, it then has the required 46 chromosomes.
- Then the fertilized egg begins to divide by mitosis.
Plants are referred to as "_______"...
These are referred to as "autotrophs" because they are nourished ("troph") by making their own organic molecules ("auto").
Animals are referred to as "_________"...
These are referred to as "heterotrophs" because they are nourished ("troph") by eating others ("hetero").