domains of life Flashcards
define prokaryotes. what are their characteristics? (5) (not well supported but still used as a group)
- A general grouping of organisms
- “before nucleus”
- Lacks a membrane bound nucleus
- Lack many specialized cell structures (organelles)
- Contain domain bacteria and domain Archaea
- Archaea grow in harsher environment
define Eukaryotes. what are their major characteristics? (2)
• A general grouping of organisms that have a nucleus (karyon)
• Contain cell organelles
• Organism in common groups of protists, plants, fungi, and animals
•
what domain are prokaryotic? what size are they?
Bacteria and archaea.
most = 1-10um diam.
Smaller
describe genomic DNA of prokaryotes? do they have membrane bound organelles?
single loop, no histones (exception=Archaea)
no nuclear membrane
none
what domain are eukaryotic? size?
Eukarya (protists, fungi, plants, animals)
most = 10-100um diam.
Larger
describe genomic DNA of Eukaryotes. membrane bound organelles?
linear chromosomes, histones
nuclear membrane
Many (mitochondria,E.R., chloroplasts, golgi, etc.)
describe cytoskeleton and cell wall of prokaryotes
> Different proteins
Domain Bacteria-
Peptidoglycan in most (Domain Archaea lack this)
describe ribosome type and cell division of prokaryotes.
70S
Binary fission
what shape are prokaryotes?
cocci, bacilli, or helical
describe flagella, cillia, and sexual reproduction of prokaryotes.
simple flagella (flagellin protein)
no cilia
no meiosis, transfer of DNA fragments (conjugation)
describe cytoskeleton and cell wall of eukaryotes
> Present (microtubules, microfilaments, intermediate filaments)
May be absent (animal cells) when occurs = simple structure (cellulose, chitin)
describe ribosome type and cell division of eukaryotes.
> 80S (70S in some organelles)
>Mitotis: meiosis
describe shapes of eukaryotes
Varied
describe flagella, cillia, and sexual reproduction of eukaryotes.
> complex flagella and cilia
(9 + 2 microtubules)
Meiosis and fusion of
haploid nuclei
what is peptidoglycan?
• Peptide and sugar mixture cell wall is made from
• What is a phylogeny?
Phylogeny, the history of the evolution of a species or group, especially in reference to lines of descent and relationships among broad groups of organisms. (tree diagram)
• What are some general characteristics of Domain Bacteria?(4)
- Mostly lack internal cell organelles
- Antient lineage (with diverse evolution metabolically)
- Important roll in ecological decomposition
- Contain peptidoglycan in cell wall (some have lost it)
describe the shapes used to describe bacteria
o Cocci (singular Cocus): circular, singular o Bacilli (singular Bacillus): singular, staff and rod shaped o Spiralla (Spiral): spiral and singular
do bacteria have cell organelles? do all have peptidoglycan?
• not usually
• Do all Bacteria have peptidoglycan?
diagnostic but some have lost it
• As humans, do we contain healthy bacteria and unhealthy bacteria? What are some of the roles in our human health?
- Yes, roughly 6 pounds. Healthy bacteria keep the unhealthy bacteria in check.
- They play a key role in our health
• What are the general characteristics of Domain Archaea? (6)
- Found in more extreme environments
- Found widely in the ocean
- Grouped into: methanogens, thermophiles, halophiles
- Lack peptidoglycan
- Know very little about this group
- Bright colors/ pigments
define the groups of domain archaea
o Methanogens: archaea that grow under high methane conditions. Ie: sediments of swamps, sewage and GI tracks
o Thermophiles: grow under high temps ie hot springs
o Halophiles: grow under high salt conditions ie the dead sea
what are some general characteristics of domain Eukarya?
- Found widely across our planet
- Contains a membrane bound nucleus
- Contain organelles (compartmentalization)
- Lacks peptidoglycan (use other substances in cell walls)
define compartmentalization
• Division into categories ie formation of compartments with organelles
define cell and cell membrane
o Cell: structural and functional unit of life or the smallest unit carrying on the functions of life. “the building blocks of life”. Eukaryotes and prokaryotes
o Cell membrane: lipid molecules assembled into a bilayer containing the cell (a cell membrane or plasma membrane).
define DNA and RNA
o DNA: deoxyribonucleic acid. Genetic system based on dna.
o RNA: system of information transfer (DNA to RNA to protein)
mRNA and tRNA
o Messenger RNA (mRNA): system of protein assembly using messenger RNA and TRNA
o Transfer RNA (tRNA): lInk between MRNA and amino acid sequence of proteins
o Reliance on proteins as a major structural and catalytic molecule
describe ATP and glycolysis
o ATP: used as the molecule of chemical energy
o Glycolysis: breakdown of glucose to make ATP
what are the seven properties common to all cells?
1. cellular organization
define life
o Life: a set of properties or a list of characteristics
define metabolism
o Metabolism: the biochemical reactions that allow a cell or organism to extract energy
define irritable and homeostasis
o Irritable: having the property of responding actively to stimuli
o Homeostasis: an organism’s process of maintaining a stable internal environment suitable for sustaining life
define evolution
o Evolution: gradual change in the characteristics of animals or plants over successive generations
• What are the 7 properties of life?
1. Displays order-arrangement
