Biodiversity Unit 1

Approximately how many years ago was the Universe formed?

13-14 billion

Approximately how many years ago was Earth formed?

4.6 billion

Approximately how many years ago did life on Earth begin?

3.5 billion

What is the Haldane-Oparin hypothesis?

Suggests that life began via biochemical processes.

What role do simple molecules play in the Haldane-Oparin hypothesis?

They could drive chemical reactions that eventually produce life.

What did the Miller-Urey experiment discover?

Organic molecules could be combined in lab settings that simulated conditions on early Earth

What do contemporary scientists believe regarding the early atmosphere?

Ammonia and methane were not present. More likely CO, CO2, NO2, and H2O

Panspermia theory

Rocks from outer space provided organic materials that could have been the catalyst for life on Earth

Development of Cell-like Bodies

All life forms have cell membranes composed of phospholipids

Define phospholipids

Fats that build the outer protective walls of cells

The "RNA World" Theory

RNA came before DNA due to the discovery of retroviruses and their use of the reverse transcriptase enzyme

What does the reverse transcriptase enzyme do?

Converts RNA to DNA

What does an aquatic setting favor regarding organic materials?

The disassembly of large molecules via hydrolysis rather than the assembly of larger ones

Why may someone believe that heterotrophic anaerobes were the first living beings?

Geology suggests that there was very little oxygen in the early Earth's atmosphere

Define heterotroph

Organism that cannot produce its own food

Define autotroph

Organism that produces its own food

Define chemotroph

Organism that gets energy by breaking down chemical compounds

Define phototroph

Organism that gets energy from light

Define cyanobacteria

Bacteria found in water

Anoxygenic Photosynthesis

Photosynthesis switched from H2S to H2O

What was the negative impact of the shift in photosynthesis?

Rising oxygen levels destroyed the greenhouse gases in the atmosphere, which resulted in mass global cooling and extinction of anaerobic microbes

Precambrian Era

4.6 billion years ago

Paleozoic Era

541 million to 252 million years ago

Mesozoic Era

252 million to 66 million years ago

Cenozoic Era

66 million years ago, (extinction of the dinosaurs), to the present day

Plate tectonics

Heated magma moves from the Earth's interior to the surface in the shape of plates that may also be covered by oceans

Pangaea

Supercontinent formed in the early Mesozoic era

Two portions of Pangaea after plate tectonics

Laurasia and Gondwana

Cretaceous Extinction

Dinosaur extinction 65 million years ago

What methods do we use to classify organisms?

morphology, behavior, genetics, and ecology

Define taxonomy

science of naming and classifying species

Binomial nomenclature and Linnaeus

2 part scientific naming process

Parts of binomial nomenclature

Genus (major family) and species

Divine King Phillip Came Over From Greece Singing

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Endosymbiotic hypothesis

mitochondria and chloroplasts were originally their own organisms but found their way into host cells through either phagocytosis or parasitism

Mitosis

creates 2 identical body cells for growth or repair

Meiosis

creates 4 unique sex cells for sexual reproduction

Zygotic type

zygote produces unique haploid spores via meiosis

Gametic

diploid organism produces gametes via meiosis

Sporic

diploid organism produces haploid spores via meiosis

(KA) Kingdom Archaezoa

organisms that lack mitochondria but contain a nucleus

(KA) Give an example of a member of the kingdom archaezoa and identify the problems it may cause

Giardia, a microscopic parasite that causes gastrointestinal problems

(KP) Kingdom Protista

Diverse group whose organisms have different ancestors instead of one common one

(KP) How is classification determined in the kingdom protista?

ecological role: consumer, producer, or both

(KP) Heterotrophic protists

gain energy by consuming matter from other organisms

(KP) water mold- phylum chrytridiomycota

microscopic fungi that uses a distinct swimming spore

(KP) water mold- phylum oomycota

group of fungi that breaks down dead matter in aquatic settings

(KP) slime mold- Phylum myxomycota

one huge cell with many nuclei

(KP) slime mold- Phylum myxoycota two parts

plasmodium, sporangium

(KP) slime mold- pseudoplasmodium

many cells that move and feed collectively

(KP) slime mold- acrasin (cAMP)

pheromone that is released by a cell that found food to attract other cells to join the pseudoplasmodium

(KP) animal like protist- phylum sarcodina

single celled protist that moves and catches food by using pseudopodia

pseudopodia

false feet

(KP) animal like protist-foraminiferans

single celled protists that build hard outer protective shells

(KP) animal like protist- radiolarians

single celled protists that build glass-like skeletons

(KP) animal like protist- phylum ciliophora

single celled protists defined by their hair like structures

(KP) animal like protist- phylum ciliophora- contractile vacuole

organelle that pumps water and waste out of the cell to maintain balance

(KP) animal like protist- phylum ciliophora- trichocyst

rod shaped structure under the surface of single celled organisms used to scare away predators

(KP) animal like protist- phylum mastigophora

single celled organisms that move using flagella

(KP) animal like protist- phylum mastigophora- trypanosoma

african sleeping sickness, transmitted through the tsetse fly, attacks central nervous system

(KP) animal like protist- phylum mastigophora- trichomonad

causes inflammation in human reproductive tract

(KP) animal like protist- phylum mastigophora- choanoflagellate

closest living relative to animal kingdom, has a cell structure similar to sponge cells

(KP) animal like protist- phylum apicomplexa

spore-forming parasites that need a host because they are non-motile

plasmodium & malaria- sporozoite stage

sporozoites and saliva are transmitted into the host’s blood

plasmodium & malaria- cryptozoite stage

parasite develops in a non-blood tissue cell, usually the liver

plasmodium & malaria- merozoite stage

parasites consume red blood cells, diminishing the health of the individual

plasmodium & malaria- gametocyte stage

asexual blood parasites convert into gamete, mosquitoes consume them to spread disease

(KP) Mixotroph protists

protists that gain energy through different methods

(KP) Mixotroph protists- phylum euglenophyta