1. Entry slip: none today
Unit 2: Respiration
Lesson 2.1- Distinguish between cellular
respiration, internal respiration and external
respiration
(pp334-337) of Biology-McGraw-Hill Ryerson)
I. Respiration: The process by which the body
brings oxygen gas, O2, from the atmosphere
to every cell in the body. As well, the process
by which carbon dioxide gas, CO2, is removed
from every cell in the body and released into
the atmosphere.
a. O2 and CO2 move through the body by one
of two ways:
i. Transportation by red blood cells
(RBC’s) of the circulatory system.
ii. Diffusion: the molecules go from an
area of high concentration to low
concentration. Remember: demo w/
sugar and water.
II. Types of respiration

2. a. Cellular Respiration: “Inside the cell”
Occurs mainly in the mitochondria of
each cell, where O2 is combined with
CHO’s or lipids and turned into energy,
CO2, and water. Cells need O2, and
produce CO2,which has to be removed.
b. Internal Respiration: “Between the cells
and bloodstream” The exchange of O2 and
CO2 between capillaries filled with RBC’s
and the cells the capillaries run by
(diffusion).
i. The oxygen in O2-rich blood in a
capillary diffuses across the capillary
wall into a cell that is O2-poor. At the
same time, CO2, from the cell diffuses
across the capillary wall into the CO2-
poor blood, to be carried away.
c. External Respiration: “Between the
bloodstream and air” The exchange of O2
and CO2 between air in the lungs and
blood in the lungs.

3. i. The oxygen in O2-rich blood in from
the air diffuses across the lung tissue
wall into a capillary carrying blood
that is O2-poor. At the same time,
CO2, from the RBC’s diffuses across
the capillary wall into the CO2-poor
air, to be exhaled.
III. Homework Assignment: Complete
“Interpreting the Concentrations of Gases in
Inhaled and Exhaled Air” for Monday. Ignore

4. Q#2. For Q #1, answer the question with one
sentence for each gas type.