BI276 chapter 1

microorganisms

an organism that is too small to be seen by the unaided human eye

microbial communities

two or more populations of cells that coexist and interact in a habitat

A microbial culture

a collection of microbial cells grown using a nutrient medium

A medium

a liquid or solid nutrient mixture that contains all of the nutrients required for a microorganism to grow.

growth

the increase in cell number as a result of cell division

colony

a macroscopically visible population of cells growing on a solid medium, arising from a single cell

cytoplasimic membrane

a permeability barrier in the cell that seperates the inside of the cell

cytoplasm

aqueous mixture of macromolecules, small organic molecules, various inorganic ions, and ribosomes 

examples of macromolecules

proteins, lipids, nucleic acids, and polysaccharides 

ribosomes

structures responsible for protein synthesis

cell wall

lends structural strength to a cell

cell wall is a relatively permeable structure. True or false?

True

where is the cell wall?

outside the cytoplasmic membrane

what is labeled?

cell wall, cytoplasmic membrane, nucleoid, cytoplasm, plasmid, ribosomes

what is labeled?

cell wall, cytoplasmic membrane, mitochondrion, nuclear membrane, nucleus, ribosomes, endoplasmic reticulum, cytoplasm, golgi complex

organelles

assortment of membrane-enclosed cytoplasmic structures

examples of organelles

nucleus, mitochondira, and chloroplasts

two different groups of prokaryotic cell structures

bacteria and archaea

prokaryotic cells lack…

nucleus and organelles

genome

the full sey of genes in a cell

gene

a segment of DNA that encodes a protein or an RNA molecule 

genome is the living blueprint of..

organism, the characteristics, activities, and very survival of a cell 

chromosomes

the genomes of prokaryotic and eukaryotic cells are organized into structures

the chromosome aggregates within the prokaryotic cell to form….

the nucleoid

nucleoid

a mass that is visible in the electron microscope but which is not enclosed by a membrane

prokaryotic cells have 2 chromosomes. True or false?

False, Prokaryotic cells have only one

plasmids typically contain….

genes that are not essential but often confer some special property on the cell. 

eukaryotic cells typically have small and compact genomes. true or false?

False, they typically have much larger and much less streamlined genomes.