Module 1 - Tree of Life Flashcards
Lecture 2-4 (48 cards)
Evolution
change in heritable characteristics of biological populations over generations
single cells were:
the first organisms, prokaryotes, basic unit of life
Single-celled organisms produce…
two genetically identical cells
multicellular organisms reproduce
asexually and sexually
Producers:
use sunlight and photosynthesis to create their own food converting sunlight to chemical energy and food
Consumers:
use chemical energy from other living organisms (plants/animals)
species
group of interbreeding organisms producing fertile offspring
evolution
changing characteristics of a group over time
7 characteristics of life:
- selectively permeable barrier (cell based)
- inheritance (DNA)
- Replicate (reproduction)
- get info (perception of environment)
- power & sustain (metabolism)
- grow to maturity
- adapt and evolve (change)
microbe
organism to small to see with the naked eye
microbiome
community of microbes (like bacteria) that inhabit a particular environment
3 domains of life:
Bacteria, Archaea, Eukarya
what does a prokaryote not have
membrane-bound organelles, nucleus
all domains have distinct…
ribosomal RNA
all prokaryotic cells have:
metabolism, growth, evolution
Prokaryote Quorum Sensing
Colony forms when enough bacteria attach to one spot, signal molecules alert when the mass is big enough (quorum sensing) then bacteria break off
prokaryotes have a lot of …
metabolic diversity
mixotrophs
a nutritional opportunist, can use energy and. carbon from a variety of sources to fuel growth and reproduction
ecological importance of prokaryotes
- decompose and recycle raw materials
- producers: the photosynthetic organisms that fix our carbon
- nitrogen fixers: converts nitrogen to usable organic forms
- disease causers: some cause disease
Prokaryotic importance to humans
- antibiotic producers; help research new antibiotics
- fermeters
- mutualists: keep us healthy and asist metabolism
- bioremediators: some can eat pollutants (oil/plastic)
Eukaryotes have…
a nucleus, membrane-bound cells/nucleus
Endosymbiotic Theory
ancestral eukaryotic cell ate a prokaryote = early eukaryotic cell
evidence for the endosymbiotic theory
mitochondria and chloroplasts:
- reproduce the same way as prokaryotes
- have similar DNA and ribosomes as prokaryotes
- have two membranes, one more similar to prokaryotes and one more similar to eukaryotes
Linnaean Classification
taxonomy/science of naming, defining and classifying groups of organism based on shared characteristics