Warm-Up 9/13/11 or 9/14/11

The mold on this bread is alive. Make a list of things that you have in common with it. These characteristics are what classify both of you as living things.

Warm UP

List all the living things and nonliving things in your pictures (make 2 lists).

Include all the things that would be there that you might not see

All living things….

1. Are made of cells. Some are made of just one cell and are called

unicelluar. Some contain more than one cell and are called

multicellular.

2. Are based on a universal genetic code in the form of DNA.

3. Maintain a stable internal environment in a process called homeostasis.

4. Taken as a group, evolve or change over time. (Species only, never individuals.)

All living things…

5. Grow and develop. Growth: Increase in size as a result of generating

more cells. Develop: Become more complex during their life

span.

6. Reproduce or make more of themselves. Asexual reproduction: only one individual is

involved, offspring are clones of the parent and each other.

Sexual reproduction: two individuals are involved. There is genetic diversity as each parent donates ½ the DNA of the offspring.

All living things…

7. Sense and respond to stimuli (changes in the environment)

8. Obtain and use materials and energy. The process in which they build or break down materials is called metabolism.

Autotrophs are organisms that are capable of creating their own energy source through photosynthesis or chemosynthesis.

Heterotrophs are organisms that get their energy from eating other organisms.

Structural levels of organization In order from smallest to largest Atom * Molecule Organelle * Cell Tissue Organ * Organ System * Organism Population Community Ecosystem Biosphere

• = NOT in book. Please know anyway.

Atom

Basic unit of matter Ex. Oxygen

Molecule

Groups of atoms combined together Have names and formulas Ex. Salt (NaCl), Water, Carbon Dioxide

Organelle

Structures of the cell formed by groups of molecules.

Ex. Mitochondria, chloroplast, lysosome

Cell

Basic unit of all living things in both structure and function.

The smallest thing that can be alive. Ex. Plant cell, Animal cell, nerve cell

Tissue

Groups of similar cells working together with a common function

Ex. Muscle tissue, nervous tissue, adipose tissue

Organ

Composed of two or more tissue types that perform one or more common function.

Ex. Brain, Stomach, Heart

Organ System

Group of organs w/ common function Ex. Respiratory system, digestive system,

Cardiovascular system

Organism

One living thing considered as a whole, many organ systems working together.

Ex. Frog, cat, fish, human, bacterium, geranium plant, amoeba

Population

group of organism of one type that live in the same area and are able to reproduce.

Ex. School of tuna, pride of lions, gaggle of geese

Community

Many different populations in an area Ex. Duxbury, Pond, River, Marsh

Ecosystem

Many communities in an area and all the non-living factors

Ex. Rainforest, forest, tundra

Biosphere

All land, air and water where life exists Ex. Earth

Why Viruses Are NOT living things..

Viruses are not cells. They do not have a cell membrane or other components of living cells.

Living host cells are required for their reproduction. Outside of the host, they act as nonliving chemicals.

They do not grow and cannot move on their own. They do not metabolize or respond to stimuli. They have genetic material and can therefore

mutate and evolve. (either DNA or RNA) They form parasitic relationships with living

organisms; the virus benefits at the expense of the living organism. (obligate intracellular parasites)

Viral Structure

Viruses contain an inner nucleic acid core (genetic material) and an outer protein coat (capsid).

The virus may also contain some enzymes.

An outer envelope (membrane) that is derived from the cell membrane of the host cell may surround the capsid.

NEVER cured a virus. Prevent = vaccine Live through and get immunity or die

T

Virus Odds and Ends

Odds and Ends: Coined the Latin name "virus" meaning

poison. Virology - the study of viruses Deadly viruses are said to be

virulent. Viruses couldn't be seen until the

electron microscope was invented

Generalized structure of a bacteriophage:

Anatomy of HIV (animal virus)