Respiration Flashcards
What is aerobic cellular respiration?
organisms use oxygen to extract energy from food
What is anaerobic respiration?
Orgs don’t use O2 to extract energy from food but instead use a different compound (nitrate/sulphur)
What are the benefits of Aerobic respiration?
- Releases more ATP molecules than ana resp
- May have allowed for the evolution of multicellularity and larger org size
What are the benefits of Ana resp?
- Quickly releases energy
Can occur in low O2 environments.
How did mitochondria evolve in the cell?
2 hypothesis:
1. Eukaryote host engulfed an aerobic prokaryote (traditional view)
2. Prokaryote host engulfed a facultative anaerobic prokaryote
Explain the role of O2 and evolution
Look at Celeste’s Notes on Insect EX
Explain bacteria and archaea resp:
Can respire aerobically, anaerobically, or both.
What is obligate aerobic reps:
Cannot survive WITHOUT O2
What is obligate anaerobic resp?
Cannot survive in the presence of O2.
What is facultative anaerobic resp?
- Can grow without O2 but use O2 if its present.
- Anaerobic bacteria use other compounds such as hydrogen sulphide or methane instead of using O2
Explain how resp occurs in Fungi:
- Most fungi are aerobic but some are anaerobic
- In soil Hyphae absorb O2 from tiny air spaces in between soil particles.
-O2 and CO2 can move across the thin outer wall of hyphae by absorption
Explain the process of fermentation:
Using bacteria or yeast to break down starch and sugar
Explain the process of plant resp:
- All parts of a plant need to respire
- Plants obtain oxygen via diffusion through:
a. Stomata (leaves and stems)
b. lenticels (stems and woody plants and some roots).
Explain how light affects plant resp:
- When dark (minimal light): only resp occurring, O2 taken in , CO 2 released.
- When light: respiration < photo, O2 released, CO2 taken in.
Describe the different type of plant roots and why this is important:
- Aerial roots: pneumatophores are useful in environments with anoxic or water legged soil.
- Aerenchyma: small air pockets in plant tissue. Allows for exchnage of gases from exposed parts of the plant to submerged parts. (Aeranchyma = bigger in stagnant water).
Why are plant leaves important?
- Leaves/some stems have STOMATA which are tiny openings allowing for gas exchnage
- Stomata present in the sporophyte generation of all land plants (except __).
- Stomata can open and close depending on plant condition and environment.
What are the different types of gas exchange systems?
- Direct diffusion
- Integumentary exchange
- Trachea
- Gills
- Lungs
What are the four stages of resp (not all animals use all four)?
- Breathing
- Gas exchange
- Circulation
- Cellular respiration
Explain what occurs during direct diffusion, and why only small animals can use this method:
- Small animal obtain O2 through direct diffusion
- DD of O2 across outter membrane can supply O2 to all cells
- Larger animals - cannot use this method bc diffusion would not be able to provide O2 quickly enough.
What is integumentary exchange?
- Skin used as gas exchange surface
- Gases then dissolve into circ system
- must occur in a moist environement
E.G. FROGS
How does the trachea allow for GE?
- Insects have a system of tubes (trachea) branching throughout their body to provide O2 to all cells
- Openings of trachea = spiracles (open and close when needed)
- some insects ventilate the tracheal system with muscle contractions
- Separate to circulatory system
Explain how Gills assist in GS/R:
- Several in a cavity/externally
- highly folded thin tissue filaments
- water passes over the gills and O2 rapidly diffuses across the gills into the CS/Coelomic fluid
- Counter current system
Explain the role of lungs in Resp/GE in relation to different animals:
- Amphibians: simple sac like lung
- Reptile: vary tend be sac like but sometimes divided, use asthmaery pump to pump the lungs by using the body wall.
- Mammals: have branching lungs that terminate in tiny air sac (alveoli)
- Birds: Composed of a parallel series of tubes (parabronchi) - air sacs inflated and deflated in a complex sequence to push air through the lungs (takes two breath cycles to complete).
Give an example of a miscellaneous respiratory system:
- Sea cucumbers: specialised resp system/tree inside the anus (breathing through the butt)
- Fitzroy river turtles: can obtain up to 70% of its O2 needs through its cloaca
- Sloth - organs are attached to ribcage so it doesn’t press on diaphragm when hanging upside down
- Diving bell spider - special hair on body to hold air bubbles as dive into water.
