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Flashcards in Test 1 Deck (51):

Know what gasses were present in the earth’s atmosphere before 2 bya. Know relative proportions (p 508)

Gasses that were present: nitrogen (N), carbon dioxide (CO2), methane (CH3), ammonia (NH3), hydrogen (H) , and hydrogen sulfide (H2S).
· Proportions: Low O2, High N and CO2


Know what autocatalytic RNA molecules are (p.509)

RNA that self replicated and could catalyze


Where was the first hereditary information found? (p. 509)

RNA, it can carry genetic info and also be autocatalytic


Why would the evolution of life switch to DNA to carry the genetic code? (p. 510)

Switched from RNA to DNA b/c DNA is more chemically stable and replicates with fewer errors


What allowed earth’s early chondrites to survive and also allowing the earth’s original amino acids. Know what the source was (p. 509)

The early atmosphere was dense, slowing down the chondrites which contained at least 80 different amino acids


Determining absolute dates by radiometric dating requires what things? (p. 512)

Accumulation of daughter isotopes; loss of parent isotopes


What role did cyanobacteria play in earth’s development? (p. 516)

Cyanobacteria contributed the most to developing the earth’s early atmosphere; made oxygen later it’s why the atmosphere is what it is


What event took place at the end of the snowball earth period? (p. 517 – 518)

The Cambrian Explosion – accelerated growth of life


How far back does the body fossil record go? (p.514, Fig 25.7)

3.5 BYA


What effects or causes does 2 continental landmasses have when they converge? (p. 520)

Global Climate Change
· Change of ocean currents and wind patterns
· Net loss of inter-tidal zones and habitats
· Extinction of many species


In regards to morphology, how would Linnaeus classify organisms differently than modern biologists would

Linnaeus would have classified the Hawaiian sliver swords as multiple species


What would you expect from an organism with a large number of hox genes?

Hox genes are responsible for the growth of body parts, where they grow, and how big. If you have more hox genes you will be more complex organism. Provides positioning information


Know what Homeotic genes are (p. 526)

Basic features of positional information hox genes are type of homeotic genes


Understand the roles that different anatomical features may have.

For example: feathers were used for warmth before they were used for flight. Or that a lung can be used as a swim bladder when fish evolve. Lung changed into swim bladder in fish. This is called EXAPTATION


What does exaptation mean?

When a body part is utilized for a new purpose than it was before


Know why plants, fungi, and prokaryotes are placed in different Taxa (p. 557)

Their cell walls are made of different stuff


Where is peptidoglycan most commonly found?

Gram + bacterial cell walls, gram + has more peptidoglycan and gram- less peptidoglycan


What is plasmolysis?

When the cell membrane pulls away from the cell wall due to loss of water
sugar will lyse the cell wall of bacteria.


What are the unique characteristics of endospores? (p. 560)

They can survive harsh climates for long periods of time. BUT endospores are NOT present in all bacteria. They are also immune to acidity.


Understand and know what structures/processes are involved in conjugation

Sex pili and stuff


. Know what is produced by Gram – bacterial cell walls

Only in gram negative ENDOTOXINS are released


Know the characteristics of cyanobacteria (p.589, 564)

· Photoautotrophic (photosynthesis)
· Nitrogen fixation


What are ways that prokaryotes protect an enzyme from oxygen? (p. 564)

· Capsules – form capsules to protect
· Obligate Anaerobes – live with out air


What is horizontal gene transfers?

The mitochondria acquire their genes because they are descendants of the Prokaryotes


Characteristics of bacteria lacking peptidoglycan (archae).

· They have an optimal pH that is less than 7.0,so they like an acidic environment


Understand sign between peptidoglycan and a thermoacidophyle

One is Archaean and one is a hot acid


Know and understand why prokaryotes have been so successful on earth

· Large Biomass
· Reproduce Quickly
· More diverse habitat
· More diverse metabolism


What is the danger of over-use of antibiotics?

Bacteria will evolve bacterial resistance


How would a host respond to a broad sense of antibiotics?

Nutritional deficiency


Know how intestinal bacteria play a role in our nutritional absorption

Produce vitamins and protect us


Know that protists are Eukaryotes



What are some examples of strong evidence that there are endosymbiotic organisms in eukaryotes? (p. 578)

· Mitochondria
· Chlorophyll


Know what a mixotrope is and what allows it to survive

They combine photosynthesis and heterotrophic nutrition. So if a mixotroph loses its plastids it can still survive by eating other organisms. Mixotrophs survive by phagocytosis and absorption.


Know a list of bacteria and which would be able to avoid the immune system?

Trypanosome – hide inside cells change antigens,sleeping sickness
· Plasmodium – Malaria
· They can evade the human immune system by changing their surface proteins


What are dynoflagellates? (p. 582)

· They make the red tide
· Have 2 flagella
· Walls composed of cellulose plates
· Many types contain chlorophyll


What are ciliates? (p. 584)

· Use cilia for locomotion
· They are complex organisms
· Primarily live in fresh water
· Have 2 or more nuclei


. Understand why convergent evolution is taking place between the water molds and fungus hyphae

Common need for the decomposers to absorb nutrients by increasing surface area through hyphae (long projectiles)


Know what caused the Irish Potato famine

Oomyctes (water/Slime molds)


What is Silica and where is it found most

Marine sediments consisting of radiolarian shells; built on silica backbone (CLIFFS OF DOVER); They are found in Diatoms


Know what Foraminifera are (p. 589)

Protists, eukaryotic, tests or porous shells and have pseudopodia that extend and function in swimming, test formation, and feeding.


Red Algae

Absorbs blue and reflects red


A-Know how colors are projected and how that pertains to algae (p. 590)

Coloring is what they reflect


What is Brown Algae?

The largest sea weeds belong to brown algae. They are the most abundant


. Know the 5 (or so) main points about protists.(p. 595, 594)

Extremely diverse collection, photoautotrophs,heterotrophs, mixotrophs, so diverse because of endosymbiosis


Know the general characteristics of fungi.Know what they do, and how they absorb food

Decomposers, they throw up/ secrete hydrolytic enzymes and then absorb nutrients. Cell wall composed of chitin


Know what the fungal enzymes do.

They secrete enzymes through hyphae hydrolytic enzymes and then absorb nutrients


Know groups or phylum that have protective chitin shells or coverings (p. 637)

Arthropods, Insects, Fungi


Know what hyphae are as they pertain to fungi

Projections that create mycillium, and secrete hydrolytic enzymes, Underground


Know what pheromones are and what roles they play. (p. 639)

Pheromones are sexual signaling molecules


Know what chytridiomycota is (p. 641)

This is the phylum that contains organisms that most closely resemble the ancient fungi and there are a ton of them


Know what zygomycota is. (p. 643)

Fast growing molds/ food molds. They are very old and were once considered glomeromycota-they create their own phyla