Circulation and Respiration Tours this week Today: Circulation and Respiration

Sources of transported material

B-cells, T-cells, antibodies, nutrients, waste, O2, CO2, water, minerals, etc must be transported throughout the body Fig 42.17

Fig 42.6 B-cells, T-cells, antibodies, nutrients, waste, O2, CO2, water, minerals, etc must be transported throughout the body

Mammals have two ciculatory circuits: pulmonary and systemic Fig 42.6 Mammals have two ciculatory circuits: pulmonary and systemic

Blood flows from arteries to capillaries to veins Fig 42.10

Capillaries provide the large surface area required for these exchanges to take place.

Blood pressure changes as the blood moves from arteries to capillaries Fig 42.11 Blood pressure changes as the blood moves from arteries to capillaries

This change in pressure causes fluid to leak out of the capillaries Fig 42.16

High pressure, Fluid forced out Interstitial fluid, Recovered by… Blood in vein, More viscous

Not all of the fluid (~15%) is reabsorbed on the venous side Not all of the fluid (~15%) is reabsorbed on the venous side. This interstitial fluid is collected by the lymphatic system. Fig 42.16

Lymphatic system Fig 43.7

Because of the low pressure in veins and lymph vessels, movement of these fluids comes from skeletal muscles movements. Fig 42.14

The mammalian circulatory system is both open and closed Fig 42.3

The mammalian circulatory system is both open and closed Fig 42.3

The mammalian circulatory system is both open and closed Fig 42.3

Nutrients, Waste, O2, CO2, Water, Minerals, etc must be transported throughout the body

Gases move by diffusion: Only from high to low concentration Fig 42.28 Gases move by diffusion: Only from high to low concentration

Hemoglobin (a protein) carries oxygen in the blood Hb is carried inside red blood cells Hemoglobin (a protein) carries oxygen in the blood hemoglobin

The Respiratory System: large surface area to maximize gas exchange Fig 42.24 The Respiratory System: large surface area to maximize gas exchange ~100m2 in humans

Gas exchange occurs in alveoli Fig 42.24 Gas exchange occurs in alveoli

In the lungs, O2 diffuses into the blood, and CO2 diffuses out into the lungs.

How is oxygen delivered to where it is needed?

By adjusting blood flow… Fig 42.15

By changes in blood pH Fig 42.30

Blood Cell Lung Fig 42.30 O2 O2 Hb in RBC Cellular Respiration CO2 Low CO2 High O2 CO2 Hb in RBC O2 O2 Lung

Blood Cell Lung Fig 42.30 O2 Hb in RBC O2 Cellular Respiration CO2+H2O =H2CO3 (carbonic acid) CO2 Low CO2 High O2 (less carbonic acid) CO2 Hb in RBC O2 O2 Lung

Changes in blood pH, change binding affinity of hemoglobin Fig 42.29b

Blood Cell Lung Fig 42.30 Hb releases O2 at lower pH O2 O2 Cellular Respiration CO2+H2O =H2CO3 (carbonic acid) CO2 Low CO2 High O2 (less carbonic acid) CO2 Hb can bind O2 O2 O2 Lung

Mammalian lung function Fig 42.25

Avian lung function... Fig 42.26

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