Homeostasis & Organisation of matter

1 Homeostasis & Organisation of matter
Week 1 Homeostasis & Organisation of matter
Learning Objectives
Lecture 1 – Introduction
 List the levels of organization of living organisms
organelle, cells, tissues, organs, organ systems, organisms, populations, communities,
ecosystem, and biosphere.
 Recognise the 11 human body systems, and know the general function of each
https://socratic.org/questions/what-are-the-different-body-systems-in-human-body-and-
what-are-their-functions
https://www.youtube.com/watch?v=gEUu-A2wfSE
Circulatory
Blood carries oxygen that your body needs, and helps remove
carbon dioxide.
The heart is included in this as well as vessels (pulmonary arteries)
that carry away from the heart and veins (pulmonary veins)carry
blood back into the heart
Digestive
breakdown the food and absorb nutrients from it.
Starts in the mouth (enzymes) within the saliva and then
travels into the stomach (which contains acid), splits into
too large intestine (colon) which absorbs water and small
intestine where it absorbs nutrients
Endocrine
It also helps different body parts to communicate by secreting
chemical substances called hormones.
For example: When the sugar level in blood drops then the
pancreas(an endocrine gland) secrete glucagon which works to
increases glucose in blood.
Endocrine system is involved in controlling growth, metabolism,
sexual development, maintaining homeostasis etc
Excretory
Involves kidneys that excrete waste from the blood. Also
involves other ways to extrete waste eg sweating
Integumentary
Skin, it helps protect your organs from outside damage, it also helps
with temperature regulation and controls water loss
Lymphatic/Immune
Lymph is fluid from blood plasma surrounding cells. This
system collects filters and returns the lymph to the blood
and the major role is to help immune function.
This keeps your body safe against pathogens like viruses
and bacteria. Structures like lymph nodes, the thymus,
spleen, tonsils and bone marrow play a role in immune.
Muscular
1. Skeletal
2. Smooth
3. Cardial
Nervous
Includes the brain and spinal cords. It also controls
voluntary actions such as catching a ball as well as
involuntary actions such as reflexes.

1 Homeostasis & Organisation of matter
At the cellular level the system uses cells known as
neurons.
Reproductive
aid in the production of new individual.
Respiratory
station of gaseous exchange i.e O2 in and CO2 out of the
body.
Skeletal
supports the body and protects the internal organs(e.g rib cage
protects the heart and lungs).
The muscular and skeletal system works together to provide
movements. Besides, the skeletal system provides proper shape to
our body. Without this system, the human body can never be as
organized as it is.
Lecture 2 – Homeostasis & Terminology
 Define homeostasis
Homeo, like or similar + stasis, condition
Ie, a stable internal environment // achieved by balancing inputs and outputs
 Understand the relationship between an organism’s internal and external
environments
Intracellular Fluid (ICF) (2/3
water)
 Within cells
Extracellular fluid (ECF) (1/3
water)
 Outside body cells, internal
environment // precisely
regulated
 Interstitial fluid (3/4) and Plasma (1/4) Capillary membrane

1 Homeostasis & Organisation of matter
 Describe the components of a feedback system.
https://www.youtube.com/watch?v=Iz0Q9nTZCw4
 Contrast the operation of negative and positive feedback systems.
Positive Negative
Intensified variable
Example:
When a baby is ready to be born there is pressure on the cervix
and the pressure and hormones involves cause contractions in the
uterus which is a big part of how the baby is going to be born
More release of hormones  More contractions and pressure 
Cause more release of hormones.
When a variable triggers a counteracting response in
order to come back to some set point (stable
temperature)
Example:
Glucose (blood sugar) is too high a hormone that is
released in (insulin)
Glucose (blood sugar) is too low in the blood a
hormone called Glucagon is released
It causes the liver to release glucose in the blood
 Understand the consequences of homeostatic failure
Values of physiologic parameters drift outside normal ranges
Diseases// May affect a tissue, organ, or even a system
Changes throughout body (processes integrated) or death
Type 1 Diabetes
The pancreas (an organ that is involved in making hormones like insulin) is not working
correctly. Insulin is not produced and because of that one issue is that you are not going
to be able to get glucose (blood sugar) into your cells.
Glucose outside the cells cannot be used in cellular respiration, the cells need to take the
glucose (IN) to make (ATP) energy in cellular respiration