- Linear chromosomes within nucleus - much larger/more DNA (up to billions of base pairs)

- generally single circular chromosome that aggregates to form the nucleoid region - may also have plasmids (extrachromosomal DNA) that confer special properties (e.g., antibiotic resistance) - mall, compact (0.5 –10 million base pairs)

Lecture 2A: Introduction to the Microbial World Flashcards by IVAN Dyan

Microorganisms (microbes) are:

diverse in form/function
inhabit every environment that
supports life
many single-celled, some form
complex structures, some
multicellular
live in microbial communities

How well did you know this?

Not at all

Perfectly

Microorganisms, Major Form of Life

Oldest form of life
Major fraction of Earth’s biomass
Associated with plants and animals, and
other life forms
Affect human life (infectious diseases,
food and water, soils, animal health,
fuel)

How well did you know this?

Not at all

Perfectly

A living compartment that interacts with the environment and
other cells

The cell

How well did you know this?

Not at all

Perfectly

Elements of microbial structure that all cells have in common.

Cytoplasmic (Cell/ plasma) Membrane
Cytoplasm
Ribosome

How well did you know this?

Not at all

Perfectly

barrier that separates the
inside of the cell from the outside environment

cytoplasmic (cell/plasma) membrane

How well did you know this?

Not at all

Perfectly

matrix of macromolecules, small organics, ions, and
ribosomes inside cell, with water as the major component

Cytoplasm

How well did you know this?

Not at all

Perfectly

protein-synthesizing structures

ribosomes

How well did you know this?

Not at all

Perfectly

no membrane-enclosed
compartments(organelle), no
nucleus

prokaryotes

How well did you know this?

Not at all

Perfectly

Examples of prokayotes

Bacteria and Archaea

How well did you know this?

Not at all

Perfectly

plants, animals, algae, protozoa,
fungi
contain organelles
DNA enclosed in a membranebound compartment = nucleus

Eukaryotes

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Procaryotic Cells:
1. DNA

Not enclosed within a nuclear membrane.
A single circular chromosome.
Not associated with histone proteins.

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Procaryotic Cells: Oganelles

-Lack membrane-enclosed organelles like mitochondria, chloroplasts, Golgi, etc.

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Procaryotic Cells: Cell wall

-Cell walls usually contain peptidoglycan, a complex polysaccharide, or pseudopeptidoglycan or S-layer

How well did you know this?

Not at all

Perfectly

a large polymer that forms a mesh-like scaffold around the bacterial cytoplasmic membrane

peptidoglycan

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Procaryotic Cells: Division

Divide by binary fission

How well did you know this?

Not at all

Perfectly

a type of asexual reproduction where a parent cell divides, resulting in two identical cells, each having the potential to grow to the size of the original cell

Binary Fission

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Eucaryotic Cells: 1. DNA

DNA is;
- Enclosed within a nuclear membrane.
- Several linear chromosomes.
- Associated with histones and other proteins.

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Eucaryotic Cells: Organelles

-Have membrane-enclosed organelles like mitochondria,
chloroplasts, Golgi, endoplasmic reticulum, etc.

How well did you know this?

Not at all

Perfectly

Distinguishing Features of Eucaryotic Cells: Division

Divide by mitosis

How well did you know this?

Not at all

Perfectly

Mitosis produces two genetically identical “daughter” cells from a single “parent” cell

Mitosis

How well did you know this?

Not at all

Perfectly

a cell’s full complement of genes

genome

How well did you know this?

Not at all

Perfectly

How well did you know this?

Not at all

Perfectly

Eukaryotic DNA

Linear chromosomes within nucleus
much larger/more DNA (up to billions of
base pairs)

How well did you know this?

Not at all

Perfectly

prokaryotic DNA

generally single circular chromosome that
aggregates to form the nucleoid region
may also have plasmids
(extrachromosomal DNA) that confer
special properties (e.g., antibiotic
resistance)
mall, compact (0.5
–10 million base pairs)

How well did you know this?

Not at all

Perfectly

The properties of microbial cells. Major activities ongoing in cells in the microbial community

- Metabolism - Growth - Evolution - Differentiation - Communication - Genetic Exchange - Motility

Cells take up nutrients, transform them and expel waste.

Metabolism

Replication, transcription, translation

Genetic

Energy, biosysnthesis

Catalytic

Nutrients from the environment are converted into new cell materials to form new cells

Growth

Cells evolve to display new properties. Phylogenetic trees capture evolutionary relationships

Evolution

Some cells can form new cell structures as spore

Differentiation

Cells interact with each other by chemical messengers

Communication

Cells can exchange genes by several mechanism

Genetic exchange

Some cells are capable of self-propulsion

Motility

First cells appeared between ___ and ___ billion years ago.

- 3.8 and 4.3 billion years ago

~2.6 billion years ago.

The atmosphere was anoxic (no O2)

A condition in which the aquatic (water) environment does not contain dissolved oxygen (DO)

- anoxic

plants and animals _____ years ago

~0.5 billion years ago

live in habitats too harsh for other life forms.

Extremophiles

refers to all living organisms plus physical and chemical constituents of their environment.

Ecosystem

is the study of microbes in their natural environment.

Microbial ecology

________ microbial cells on Earth

~2 x 10^30

Temeprature, High. - an organism that thrives in extremely hot environments

Hyperthermophile

Temperature, Low. - a group of organisms with the ability to grow and reproduce under low temperatures

psychrophile

Example of Hyperthermophile

- Methanopyrus kandleri (scientific name pag sulat)

Hyperthermophile, domain and habitat

Domain: Archea Habitat: Undersea hydrothermal vents

Hyperthermophile, Minimum, optimum and maximum temperature.

Minimum: 90°C Optimum: 106 °C Maximum: 122°C^b

psychrophile, domain and habitat

Domain: Bacterial Habitat: Sea Ice

psychrophile, Minimum, optimum and maximum temperature.

Minimum: -12 Optimum: 5°C Maximum: 10°C

Are organisms that can withstand and even thrive in acidic environments

Acidophile

microorganisms that grow optimally or very well at pH values (above 9).

Alkaliphile

Example of Acidophile

Picrophilus oshimae (Scientific name page sulat)

Example of Alkaliphile

Natronobacterium gregoryi

Acidophile, domain and habitat

Domain: Archea Habitat: Acidic Hot springs

Alkaliphile, domain and habitat

Domain: Archea Habitat: Soda lakes

Acidophile, Minimum, optimum and maximum pH.

Minimum: -0.06 Optimal:0.7^d Maximum: 4

Alkiliphile, Minimum, optimum and maximum pH.

Minimum: 8.5 Optimal: 10^e Maximum: 12

are defined as organisms which grow optimally or preferentially at pressures greater than atmospheric pressure

Barophile (piezophile)

Example of Barophile (piezophile)

Moritella yayanosii (scientific name pagsulat)

Barophile, domain and habitat

Domain: Bacteria Habitat: Deep ocean sediments

Barophile, Minimum, optimum and maximum atm. (atmospheric pressure)

Minimum: 500 atm Optimum: 700 atm Maximum: >1000 atm

an organism, especially a microorganism, that grows in or can tolerate saline conditions.

Halophile

example of halophile

Halobacterium salinarum (scientific name pagsulat)

Halophile, domain and habitat

Domain: Archea Habitat: Salterns

Halophile, Minimum, optimum and maximum saline.

Minimum: 15% Optimum: 25% Maximum: 32% (saturation)