NEW - EXAM STYLE QUESTIONS AND ANSWERS 1 Flashcards
ON HOMEOSTASIS
In this deck of cards, I have took real life examination questions from past papers and stated how I would answer the following questions including how many marks each one has.
This deck of cards focusses on Homeostasis. A CORE QUESTION.
These are all questions I have personally answered and achieved the full mark set so please ensure you are understanding and taking into account the key words.
Explain the role of negative feedback in homeostasis.
(6 marks)
Negative feedback is a mechanism used by the body to maintain homeostasis. It involves a response that decreases the original stimulus.
In negative feedback, if the body senses a change in a particular variable, it triggers a response that reverses the change and brings the variable back to its set point.
Examples of negative feedback in homeostasis include regulation of body temperature, blood glucose levels, and blood pressure. When these variables deviate from the set point, negative feedback mechanisms are activated to restore balance.
(this would achieve the whole 6 marks)
Explain the role of positive feedback in homeostasis.
(6 marks)
Positive feedback amplifies or increases the initial stimulus, pushing the system further away from the initial set point. It is important in processes that need rapid change and are not required to maintain a stable internal environment.
A example of positive feedback in homeostasis is when a blood vessel is damaged, platelets release chemicals that attract more platelets to the site of injury. This leads to the formation of a platelet plug, increasing the release of clotting factors, and ultimately forming a blood clot to stop bleeding.
( full 6 marks achieved here)
Name the 2 organs that control Glucoregulation and describe the role of one these organs in glucoregualtion
(5 marks)
1) Pancreas:
It produces and releases hormones such as insulin and glucagon, which help maintain stable blood glucose levels in learners.
2) Liver:
It stores excess glucose as glycogen and produces glucose when needed to maintain blood sugar levels within a healthy range for individuals.
Analyse how thermoregulation maintains the healthy functioning of the human
body.
(12 MARKS) - A BIG MARK QUESTION HERE
Thermoregulation is the process by which the body maintains a stable internal temperature.
The body regulates its temperature through mechanisms such as sweating, shivering, vasoconstriction, and vasodilation.
The hypothalamus acts as the body’s thermostat, detecting changes in temperature and initiating responses to maintain body temperature within a narrow range.
Hypothermia can lead to slowed metabolism, cardiac arrhythmias, impaired cognitive function, and even death if not treated promptly.
Hyperthermia can cause heat exhaustion, heat stroke, dehydration, organ failure, and ultimately, can be life-threatening.
Thermoregulation is essential for human health as it helps maintain optimal metabolic and enzymatic functions, prevents overheating or hypothermia, and ensures efficient physiological processes.
(A big 12 marker achieved here - a lot to remember I know but a question alone almost worth a pass alone)
The hypothalamus and the pituitary gland work together to achieve homeostasis.
Explain this relationship
(5 marks)
The pituitary gland responds to signals from the hypothalamus and releases hormones that regulate various body functions. It helps maintain homeostasis by controlling hormone levels, managing stress responses, and facilitating growth and development.
