1. Entry slip: Give an example of a deviation related to
blood pressure.
Lesson 5.5 Describe life processes of individual
cells as well as complex organisms
(pp300-303 of McGraw-Hill Ryerson)
I. Terms:
a.Life Processes

2. i. Chemical reactions between tissues
that keep an organism alive.
b.Complex organism: an organism
composed of more than one cell (i.e. a
human).
II. Life Processes:
a.Closely involved in homeostasis, for the
purpose of maintaining a person’s
internal environment.
b.Nervous System:
i. (In terms of an individual) Cell: Nerve
cells connect the body to the brain,
and carry electronic signals between
the two.
ii. (In terms of the whole) Body:
Network of nerves senses information
from inside the body as well as the
environment around the body. The
brain then makes decisions and sends
information to the effectors.
c. Endocrine system:

3. i. Cell: Specific cells are affected by
specific hormones. Some cells make
and secrete hormones.
ii. Body: this system secretes certain
hormones into the bloodstream to be
circulated around the body in order
to give information/instructions to
specific tissues and organs.
d.Immune System:
i. Cell: Some cells in the body are
involved with immunity (WBC’s) and
fight foreign pathogens. Most
individual cells are by themselves
defenceless against an attack.
ii. Body: This system is responsible for
defending cells from foreign
pathogens as well as removing dead
cells (pus).
e.Digestive System:
i. Cell: Receives nutrients from blood
plasma by diffusion.

4. ii. Body: Obtains nutrients from external
environment and transfers them to
blood plasma for use and storage.
Eliminates undigested food as waste.
f. Transportation System:
i. Cell: Receives nutrients and
hormones, exchanges gases, and gets
rid of wastes by diffusion with the
circulatory system.
ii. Body: “picks up” and “drops off”
gases, nutrients, wastes and
hormones at various areas. Also
influences body temperature and
immune response.
g.Excretory System:
i. Cell: Cells produce CO2 and nitrogen-
containing wastes that have to be
removed.
ii. Body: removes N-containing wastes,
excess water and minerals by

5. urination via the nephrons of the
kidney. Exhales CO2 by the lungs.
h.Respiratory System:
i. Cell: Internal respiration (gas
exchange between blood and cell);
cellular respiration (gas exchange
mainly in mitochondria of cells) by
diffusion.
ii. Body: Moves CO2 and O2 between
atmosphere and individual cells, via
the circulatory system.
III. Youtube search:
a.Nervous System-chinchin85
IV.Homework:
a.Which life process is the most important?
In other words, in the absence of which
life process would the human body die
the quickest? Why?
b.-½ a page due next class.