Thermoregulation –
____
environment
body heat
endergonic
Invertebrate Respiration:
Cnidaria: Protozoa and Hydra
o Direct with ____: large surface areas and every cell is either exposed to environment or close to it -> ____ of gases directly
with outside environment (e.g. flatworms). Small animals only.
environment
simple diffusion
Invertebrate Respiration:
Annelids:
o ____ secreted by earthworm provides moist surface for gaseous exchange by ____
o Circulatory system bring ____ to cells and waste products (CO2) back to skin for excretion
mucus
diffusion
O2
Invertebrate Respiration:
Arthropods (80% of all living species – insects, spiders, crustaceans (crabs), etc…
o Grasshopper
— Series of chitin-lined respiratory tubules called ____ open to surface in openings called ____ through with O2 enters, CO2 exits. No oxygen carrier is needed due to ____ and removal of respiratory gases between air and body cells; diffusion across moistened tracheal endings.
o Spider
— ____: stacks of flattened membranes enclosed in internal chamber
trachae
spiracles
direct distribution
book lungs
Invertebrate Respiration:
Fish
o Water enters mouth, passes over ____ (evaginated structures, create large ____, take O2 and deposit CO; can be external/unprotected or
internal/protected), exits through ____ (gill cover). ____ between opposing movements of water and underlying
gills
SA
operculum
countercurrent exchange
Plant Respiration
- Photosynthesis only takes place during the day.
o Photosynthesis produces glucose and gives off oxygen
o While respiration requires oxygen to degrade glucose
stomata
lenticels
Gas exchange in human: CO2 is transported as HCO3- in the plasma (liquid portion of blood), catalyzed by ____ (____ ↔ ____ ↔ H+ + HCO3-) located in the RBC. Some CO2 mixes direct w/ plasma as gas, or binds with hemoglobin in RBCs
carbonic anhydrase
CO2 + H2O
H2CO3
Alveoli – where gas exchange between the circulatory system and the lungs occurs; ____ reduces the surface tension (prevents H2O from collapsing alveoli). There are two types of epithelial cells in human alveoli: type 1 (____) and type 2 (____)
surfactant
structural support
produce surfactant
Nose (filter, moisten, warms incoming air – mucus secreted by goblet cells traps large dust particles here), pharynx (____ – passageway for food and air; dust/mucus swept back here by ____ for disposal via spitting or swallowing), larynx (____- if ____ enters, cough reflex activates)
throat
cilia
voice box
non-gas
Trachea (____ covers the trachea during swallowing) – ringed cartilage (____) covered by ciliated mucus cells
epiglottis
C-shaped
Bronchi, Bronchioles: ____ bronchi, which enter the lungs and branch into narrower ____
Alveoli: Each bronchiole branches ends in these small sacs, which are surrounded by ____
two
bronchioles
blood-carrying capillaries
Diffusion between alveolar chambers and blood: Gas exchange across moist, sac membranes of ____. O2 diffuses through alveolar wall, through pulmonary capillary wall, into blood, and into red blood cells. (CO2 is ____)
alveoli
opposite
Bulk flow of O2: O2 transported through body within ____ containing red blood cells (RBCs)
Diffusion between blood and cells: Oxygen diffuses out of RBCs, across blood capillary walls, into ____, and across cell membranes (CO2 opposite)
hemoglobin
interstitial fluid
Bulk flow of CO2: CO2 mainly transported as ____ ions in plasma, liquid portion of blood. Produced by ____ in RBCs. CO2
can also directly mix with ____ (as CO2 gas), or bind ____ inside RBCs
HCO3-
carbonic anhydrase
plasma
hemoglobin
Bulk flow of air into and out of the lungs:
a. Inhalation – ____ (under lungs) and ____ (between ribs) contract/ flattens; increase in volume / decrease in ____ in lungs -> bulk flow of air into lungs.
b. Exhalation – ____ process; decrease in lung volume/ increase in air pressure -> air rushes out; diaphragm relaxes and ____
diaphragm
intercostal muscles
pressure
passive
expands
Bohr effect – hemoglobin O2 ____ decreases under conditions of low pH (high CO2 & [H+]) -> oxygen loads released by hemoglobin
Decrease in ____ or ____ in pH will result in hemoglobin binding more O2
Result of: CO2 + H2O -> H2CO3 -. H+ + HCO3-
binding affinity
CO2
increase
____ - Basically explains CO2’s dissociation curve. ↑ CO2 pressure = ↑ CO2 content in blood. But when hemoglobin is saturated by oxygen, its capacity to hold CO2
is ____. Essentially: we pick up CO2 in the tissues where it’s been generated, and get rid of it at the lungs and grab oxygen instead. Hemoglobin w/out oxygen acts as
____ by accepting H+ -> this reduced hemoglobin has higher capacity to form ____ rather than the oxygen carrying kind, explaining how the
Haldane effect occurs.
haldane effect
reduced
blood buffer
carbamino hemoglobin
*Oxygen diffuses from ____ into ____, CO2 diffuses from ____ into ____
alveolar air
blood
blood
lungs
Human respiration controlled by ____ – signals the diaphragm to ____
medulla oblongata
contract
increases
skeletal
phrenic nerve
mammals
Critical note: the majority of CO2 in the blood is transported in the form of the ____ (HCO3-). To a lesser extent, it can be transported bound to ____, and to an even lesser extent simply dissolved in the ____ (CO2 is ____ in blood than O2)
bicarbonate ion
hemoglobin/plasma proteins
plasma
significantly more
Bigger picture: tissues are high CO2 and high H+, and they’re not getting a lot of oxygen, we want to oxygenate them. So Hb (Hemoglobin) once near the tissues is exposed to the higher CO2/H+, and ____ to ____ form: this ____ form now releases its O2 to the tissues, and will also more preferably bind ____
changes structure
reduced
reduced
CO2
At the lungs, the CO2 wants out and is released. The H+ cxn is also lower due to bicarbonate being converted back into CO2 form for release. Now hemoglobin will change to its ____ that preferably binds ____, which it holds more tightly under these conditions.
non-reduced state
oxygen
Control of respiration: central chemoreceptors in the ____ monitors ____ in the cerebrospinal fluid (though not directly) and peripheral chemoreceptors in the carotid arties and aorta monitor aterial ____, ____, and ____. In an active body, there is increased CO2 production; it enters plasma is converted to HCO3- and H+, the blood pH drops -> respiratory rate ____. Oxygen and pH mainly monitored by the ____
medulla [H+] [H+] [CO2] [O2] increases peripheral chemoreceptors
As O2 pressure increases, O2 saturation of hemoglobin ____
increases