Applied Science AQA/Homeostasis

Topic Title
THIS TOPIC MIGHT BENEFIT FROM BREAKING UP INTO SMALLER CHUNKS.

Setting Applied context
Health professionals need to be able to relate the principles of homeostasis to health and illness, and maintaining a patient’s homeostasis is one of the most important roles of a nurse. Many of the tests that a nurse performs on a patient, such as measuring temperature or blood pressure, determine whether the patient’s body is in homeostasis or in distress. Nurses need to know about the importance of maintaining insulin levels in people suffering from diabetes, in order to prevent severe consequences of blood sugar imbalance.

Exploration of key ideas (must be original text, not C&P) – level checked by AQA
In general, point students towards the approach to take, as opposed to just giving them information.

Concept 1 - Physiological control systems
The body temperature is kept constant (from 35.8 - 37.5°C). This is done through the hypothalamus in the brain which detects changes in the temperature of the blood. The body has a range of systems that can regulate temperature, For Example, Hairs on the skin can stand upright to reduce heat loss or glands on the skin secrete sweat to increase heat loss through evaporation.

Blood Gluscose range is kept constant from 82-110 mg/dl through insulin being secreted into the blood via the pancreas, this makes the liver convert the gluscose glycogen, this makes the glusacose level go down, conversely when gluscose levels are too low the pancreas releasees glucagon this causes the cells in the liver to turn glycogen into glucose, this causes the gluscose levels to rise, this is an example of negative feedback

Blood pH range is kept constant (7.35-7.45) through breathing, skin and urine. This is done through breathing by the release of CO 2 which rids the body of acid but also when you hyperventilate you breathe in too much and increase the alkaline concentration. This is also done through the Skin via sweat and urine by the release of Urea which decreases the acidic concentration of the blood.

Concept 2 - Roles of Hormones
explanation 2

Concept 3
explanation 3

Concept 4
explanation 4

Study Task
Work to do to understand this topic e.g. research, analysis

Careers and Organisations
Carry out some research into these jobs in this area. (Feel free to add other jobs you find.)

Relevant practical/s
– relating to criteria skills

Exam-style questions
– can we use old AQA qs… e.g. from more than 5 years ago? With Examiner comments

Links
to other sections within this book

to good external websites (including AQA website, wikipedia, relevant applications / companies) - also considering links in spec

References / Bibliography
of recommended text books

including mapped refs to existing books

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