Physiology 3.1 Flashcards
What is the feeding centre?
This promotes feelings of hunger and the drive to eat.
What is the satiety centre?
This makes you feel full up, it suppresses the feeding centre.
It is insulin dependant.
What is the glucostatic theory?
The feeding and satiety centres are controlled by blood glucose levels.
High levels of blood glucose = + satiety centre, - feeding centre.
What is the lipostatic theory?
Fat stores determine food intake - controlling the feeding and satiety centres.
Increase in fat stores = +satiety centre, - feeding centre.
What hormone is released by fat?
Leptin - this depresses the feeding activity.
How many Scottish adults are overweight or obese?
2/3rds.
How do we use energy?
Cellular work - transporting molecules (non-voluntary).
Mechanical - Intracellularly (like movement of neurotransmitters down a nerve axon) or large scale - using skeletal muscle (voluntary).
Heat loss - Non-voluntary.
Which is the only voluntary form of energy output?
mechanical movement of skeletal muscle.
How much of our energy input is caused by heat loss?
Half of our energy.
What is metabolism?
Integration of all biochemical reactions in the body.
- Extracting nutrients in food
- storing that energy
- using that energy for work
What are the metabolic states of the body?
Absorptive, post-absorptive and starvation. The body usually flicks between the first 2.
What happens after eating?
The absorptive state - anabolic reactions. To store the nutrients we have just consumed.
What happens between meals and periods of not eating?
We enter the post-absorptive state - catabolic reactions. We break down our bodies nutrient stores and use them for energy.
How does the brain get its energy?
The brain can only use glucose. Except in starvation it can breakdown ketone bodies.
How does the rest of the body get its energy?
They prefer to use glucose, but can also use fatty acids or amino acids.
