Why do we classify organisms?

1. Help us to organize organisms so that they can be easily found and determine their similarities and differences.

2. Identify the unknown species.

3. Assign names to organism.

4. Make the study of a wide variety of organism easy.

A method of grouping things according to certain characteristics or

properties.

- being a feature that helps to distinguish a person or thing.

Characteristic

 The stripes that are characteristic of the zebra.

Example

An organism is generally referred to any living thing

such as animal, fungus, micro-organism, or plant.

The process of nourishing or being nourished, especiallythe process by which a living organism assimilates foodand uses it for growth and for replacement of tissues.

Animals that eat only fresh meat

Animals that eat only plants

Animals that eat both meat and plants

An organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition.

An organism capable of synthesizing its own food from inorganic substances, using light or chemical energy.

Green plants, algae, and certain bacteria are autotrophs.

The sexual or asexual process by which organisms generate new individuals of the same kind; procreation.

Reproduction by means of a cell or organism dividing into two or more

new cells or organisms

The division of a cell into two daughter cells with the same genetic material.

A mode of reproduction involving the fusion of female gamete (ovum) and male gamete (spermatozoon), which forms a zygote that potentially develops into

genetically distinct offspring.

A form of reproduction that does not involve meiosis, ploidy reduction or fertilization,

and the offspring is a clone of the parent organism ; because of no exchange of genetic material.

consisting of a single cell or only one cell

Having or consisting of many cells

Made up of only one cell

A microscopic single-celled organism which has neither a distinct nucleus with a membrane nor other specialized

organelles, including the bacteria and cyanobacteria.

an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus. Eukaryotes include all living organisms other than the eubacteria and

archaea.

5. Kingdom Monera

- made up of bacteria

Examples:

Bacteria

Consists mainly of different kinds of bacteria

• Bacteria are the simplest of all living organisms

• They are very small ( A thousand bacteria can sit side by side in just 1 millimeter)

• Bacteria were among the first life forms on Earth.

1. Bacteria posses a cell wall but do not have nucleus.

Organisms whose cells lack a membrane-bound nucleus

2. They are not completed cells.

3. Bacteria is unicellular organism (or single cell.)

Having or consisting of only one cell.

4. Bacteria can move freely from one place to another.

The word flagellum in Latin means whip

Some kinds of bacteria move by using Flagella.

Bacteria that cannot make their own food called Heterotroph

5. Some of Bacteria can make their own food but some cannot. Some get food from dead

and decaying matter.

Blue-green bacteria(algae)

can make their own food called Autotroph

6. Bacteria can be found everywhere.

7. Bacteria reproduce by cell division or binary fission.

Cell Division or Binary Fission

Bacteria have 3 major shapes: cocci, bacilli and spirilla

Cocci Bacilli Spirilla

(spherical) (rod-shaped) (twisted)

Arrangement of cocci

Cocci may be oval, elongated, or flattened on one side.

Cocci that remain in pairs after dividing are called diplococci.

Cocci may remain attached after cell division. These group characteristics are often used to help identify certain cocci.

Cocci that remain in chains after dividing are called streptococci.

Cocci that divide in multiple planes and form grape like clusters or sheets are called staphylococci.

Arrangement of cocci

Cocci that divide in two planes and remain in groups of four are called tetrads.

Cocci that divide in three planes and remain in groups cube like groups of eight are called sarcinae.

Arrangement of cocci

Bacillus is a shape (rod shaped) but there is also a genus of bacteria with the name Bacillus.Most bacilli appear as single rods.

Diplobacilli appear in pairs after division.

Arrangement of bacilli

Streptobacilli appear in chains after division.

Some bacilli are so short and fat that they look like cocci and are referred to as coccobacilli.

Arrangement of bacilli

Vibrios look like curved rods.

Spirilla have a helical shape and fairly rigid bodies.

Arrangement of Spiral bacteriaSpiral bacteria have one or more twists.

Spirochetes have a helical shape and flexible bodies. Spirochetes move by means of axial filaments,

which look like flagella contained beneath a flexible external sheath.

Arrangement of Spiral bacteria

Other shapes of Bacteria

• Stella are star-shaped.• Haloarcula, a genus of halophilic archaea,

arerectangular.

Useful of Bacteria

Some bacteria perform benefit functions, such as:

Help in returning milk into yogurt or cheese

Help to produce drugs to fight disease

bacterial vaccines

Antibacterial antibiotics

Harmful Bacteria

Most bacteria are completely harmless. However certain types are responsible for causing a variety of

diseases in human, plants and animals

Controlling Bacteria Antiseptic vs. Disinfectants

Antiseptic- chemicals that kill bacteria on living things

Disinfectants - stronger chemicals that destroy bacteria on objects or nonliving things

Examples Iodine, Hydrogen peroxide, Alcohol, Soap, Mouthwash

Characteristics of Bacteria

1. Prokaryotes – means have no true nucleus

2. They are not completed cells

3. Some are autotrophs and some heterotrophs

4. Bacteria can found everywhere.

5. They can move freely from one place to another place.

6. They reproduce by cell division or binary fission

7. Most are useful or harmless.