3/26 Daily Catalyst Pg. 99 Respiratory System 1. What is the SA/V for this cell? Round your answer to the nearest hundredths. (surface area/volume) 2. How is blood sugar levels and maintaining these levels is an example of negative feedback loop. 3. When you hold your breath, which of the following first leads to the urge to breathe? A. falling CO2 B. falling O2 C. Rising CO2 D. rising pH of the blood E. both C. and D.

1. What is the SA/V for this cell 1. What is the SA/V for this cell? Round your answer to the nearest hundredths.

3/26 Daily Catalyst Pg. 99 Respiratory System 2. How is blood sugar levels and maintaining these levels is an example of negative feedback loop. Insulin works to decrease your blood glucose (stimulus) by taking glucose into cells. 3. When you hold your breath, which of the following first leads to the urge to breathe? A. falling CO2 B. falling O2 C. Rising CO2 D. rising pH of the blood E. both C. and D. E

3/26 Class Business Quiz #25 on Friday Tutoring available after school

3/26 Agenda Daily Catalyst Class Business Reading quiz Respiratory System Video clip Chi-squared practice problem

3/26 Reading Quiz NAME: __________ Period: 3 Date: 3/26 Score: ____/4 1. Give an example of a negative feedback using blood clotting as the premise. 2. What are the 3 most common respiratory organs? 3. Why do fish receive less oxygen in water? 4. How does the structure of the lungs relate to their function?

3/19 Reading Quiz 1. Give an example of a negative feedback using blood clotting as the premise. When the blood vessel is broken, the body secretes platelets and clotting factors. When the vessel is stitched, the body will stop secreting clotting factors. 2. What are the 3 most common respiratory organs? Lungs, gills, and trachea 3. Why do fish receive less oxygen in water? There is less oxygen in water 4. How does the structure of the lungs relate to their function? The spongy texture of the lungs allow for oxygen to diffuse through and CO2

3/26 Daily Objective Organisms have various mechanisms for obtaining nutrients and eliminating wastes

Respiratory systems of aquatic and terrestrial animals

The Respiratory System Key Point #1: Gas exchange is the uptake of molecular O2 from the environment and the discharge of CO2 to the environment Once more, we see the reliance on the environment Think-Pair-Share The respiratory system is different than respiration. How does respiration rely on the respiratory system?

Key Point #2: Sources of Oxygen Terrestrial animals: Air Aquatic animals: Water Much less than air

Once more, the interaction with the environment Key Point #3: Respiratory surface is the part of the animals body where gases are exchanged with the surrounding environment The earthworm uses its entire body as a respiratory organ. Gases move by diffusion across its general body surface. Just below the skin are capillaries ready for exchange. Sponges move gases by their plasma membranes that are close to the external environment. Now the type of respiratory surface is going to depend on if the organism lives on water or land and its metabolic needs.

Stop and jot The respiratory system in an endotherm or ectotherm would be larger and why? The respiratory system of an endotherm would be larger because endotherms have increased metabolic demands and will require a larger intake of oxygen to meet the metabolic demands such as for respiration and thermoregulation. Add this answer to your notes and along with other reasons that effect how large a respiratory surface is.

Oxygen Consumption (mL) With your cooperative partner, Mass (g)

Respiratory Organs For most organisms, the skin is insufficient at exchanging gases. Solution: respiratory organs Key Point #4: Respiratory organs Gills, tracheae, and lungs The most common respiratory organs

Gills in Aquatic Animals Key Point #5: Gills are outfoldings of the body surface that are in water Yes, great aquatic environment, but oxygen content in water is much lower than air. To counter this, ventilation occurs Ventilation is increasing the oxygen over the respiratory surface Current of water

Gills in Aquatic Animals To reduce the energy cost of ventilation: Key Point #6: Blood flows in the opposite direction to the movement of water past the gills Countercurrent exchange Creates a DIFFUSION GRADIENT (High in water-low in blood) We love diffusion! Why?! No ATP is used!

Gills in Aquatic Animals Where else have we seen countercurrent exchange? Ch. 40 Vasodilation and vasoconstriction Warm temperature to core of body and cold air to our parts of the body

Gills in Aquatic Animals Why are gills unsuitable for animals living on land? Evaporation of water from gills Gills would collapse

Mammalian Respiratory System Intersection of food and air Air enters. Filtered and humidified Voice Box Windpipe. Cartilage Finer tubes Spongy texture. Site of gas diffusion Branches into the lungs Cluster or air sacs. Site of gas exchange. Capillaries

The Control Center What controls all of this? The brain Where? Key Point #7: Medulla Set the breathing rhythm and monitors CO2 levels and pH levels pH? Yes, lower pH indicated acid and more CO2 so we breathe!

Breathing control is only effective if it is coordinated with control of the cardiovascular system so that ventilation is matched to blood flow. During exercise, for instance, an increased breathing rate, which enhances O2 uptake and CO2 removal, is coupled with an increase in cardiac output. Key Point #8: The cardiovascular rate and respiratory rate are proportional to one another

Think-pair-share A slight decrease in blood pH causes the heart’s pacemaker to speed up. What is the function of this control mechanism? The pace maker sets the pace of the heart (heart beats). If the pH of the blood decreases (more acid) this means there is more CO2 in the blood and for the body to get rid of the CO2 then the blood needs to pump the CO2 to the lungs get rid of it and more O2 needs to be inhaled and delivered throughout the body by the blood.

Oxygen Carrier HEMOGLOBIN!!! Protein 4 subunits Heme group Iron at the center of each heme group 1 Fe binds 1 O2 = 4 O2 total

Cooperativity in hemoglobin Key Point #9: When one O2 binds to a heme group, the other 3 heme groups slightly change shape and increase their affinity for O2 Peer Pressure! Affects unloading too? O2

What promotes the unloading of O2? High levels of CO2 Acidic pH Lower amounts of O2

Carbon Dioxide Transport Plasma= 7% Hemoglobin = 23% Blood as HCO3- = 70% HCO3- is what is detected by the medulla to increase inhaling of O2

CO2 + H20  H2CO3 (acidic and unstable) CO2 diffuses from respiring cells to the blood and the blood flows to the lungs Concentration gradient CO2 + H20  H2CO3 (acidic and unstable) H2CO3 breaks down into H+ and HCO3-

Turn and Talk How does the increase in the CO2 concentration in the blood affect the pH of the cerebrospinal fluid? An increase in CO2 is a decrease in the pH and the fluid will detect the acidic pH and motion to the medulla to exhale CO2.

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