Homeostasis Flashcards
What is Homeostasis?
A dynamic process where we adapt and adjust to maintain equilibrium in the bodies internal environment
What are the components of a feedback system? (5)
Set point, Sensor, Control centre, effector and the regulated variable
What are the 3 main feedback loops?
Positive feedback
Negative feedback
Feedforward loops
Describe Negative feedback
Acts to reduce a change in the body
Describe Positive feedback?
Acts to increase an effect in the body
Describe feedforward loops?
Physiological responses in anticipation of a change in a variable
What are the two types of glands in the body ?
Exocrine and Endocrine
What is the difference between Endo and Exocrine
Endocrine are ductless and secrete hormones into the blood whereas Exocrines secrete theirs through a duct
What are Hormones?
Hormones are chemical messengers carried by the blood to target cells to cause a response
What are the 4 main functions of Hormones?
1) Hormones help regulate chemicals, metabolism, immune system, cardiac muscle fibres and glandular secretion
2) Control growth and development
3) Regulate operation of reproductive system
4) Help establish circadian rhythm
What are the main differences with Endocrine system and the Nervous sytem?
Endocrine act relatively slower
however have longer lasting effects
What are the 3 main structures of Hormones?
Amines, Peptides/Proteins and Steroids
How do Peptide hormones travel, compared to Amine and Steroids?
Peptides are water soluble therefore circulate dissolved in plasma whereas the others circulate bound to proteins
What is mainly responsible for removing hormones ?
The Liver and Kidney
How do hormones get to the target cells?
Lipid soluble hormones (such as steroids and thyroids) attach to receptors inside cells whereas water soluble hormones (such as proteins) attach to receptors on the membrane