BACTERIAL CELL STRUCTURE, PHYSIOLOGY, METABOLISM AND GENETICS

Dutch biologist/lens maker Ø Discovered beasties in a water droplet in his homemade microscope Ø First to study microorganisms Ø “Father of protozoology and bacteriology”

4 MICROBES ARE:

Unicellular organisms that lack a nuclear membrane and true nucleus Ø Classified as Prokaryotes, having no mitochondria, ER, or Golgi bodies Ø Absence of these structures differentiates them from Eukaryotes

Ø Eukaryotic parasites exist as unicellular organisms of microscopic size, whereas others are multicellular. Ø Protozoa are unicellular organisms within the kingdom Protista, which obtain their nutrition through ingestion. Ø Motile or nonmotile

Categorized by their locomotive structures: – _____ (whiplike) – _____ (false feet) – ____ (eyelash)

Multicellular parasites (e.g. tapeworm) may be as long as ____ to ___ meters

Heterotrophic eukaryotes that obtain nutrients through absorption

Bodies of multicellular fungi are composed of filaments called

which interweave to form mats called

filamentous forms that can reproduce sexually and asexually Ø Certain fungi can assume both morphologies (yeast and hyphae/mycelial forms) Ø Yeast at incubator or human temperature Ø Filamentous form at room temperature

produce systemic diseases

are the smallest infectious particles (virions); Ø they cannot be seen under an ordinary light microscope Ø Neither prokaryotic nor eukaryotic Ø Effects can be seen as inclusions, rounding up of cells, and syncytium (cell fusion of host cells into multinucleated infected forms)

A virus that infects and possibly destroy bacterial cells is known as a ____.

The orderly classification and grouping of organisms into taxa (categories)

Involvesthree structured, interrelated categories:

Naming assignments for each organism

based on susceptibility to specific bacterial phages.

However, more recently, taxonomists have placed all organisms into three domains that have replaced some kingdoms:

are prokaryotic cells that infect eukaryotic hosts. Targeting antibiotic action against unique prokaryotic structures and functions inhibits bacterial growth without harming eukaryotic host cells.

Ø Bacteria do not contain a membrane-bound nucleus. Ø Their genome consists of a single circular chromosome. Ø This appears as a diffuse nucleoid or chromatin body (nuclear body), which is attached to a mesosome, a saclike structure in the cell membrane

appear as highly refractile bodies in the cell. ____ are visualized microscopically as unstained areas in a cell with the use of traditional bacterial stains

consists of the membrane and structures surrounding the cytoplasm. Ø In bacteria, these are the cell membrane and the cell wall. Some species also produce capsules and slime layers.

is a phospholipid bilayer with embedded proteins that envelop the cytoplasm

is a rigid structure that maintains the shape of the cell and prevents bursting of the cell from the high osmotic pressure inside it.