INTRODUCTION TO PHYSIOLOGY. LECTURE--------1 DR ZAHOOR ALI SHAIKH. What is Physiology ?. Physiology deals with functions of the body. Central aim is to keep the HOMEOSTASIS that is to keep the INTERNAL- ENVIORNMENT of the cell constant, so that cells can work.
DR ZAHOOR ALI SHAIKH
Food + Oxygen = CO2+ H2O+Energy
1- Muscle Tissue
2- Nervous Tissue
3- Epithelial Tissue
4- Connective Tissue
1– Skeletal Muscle
2– Cardiac Muscle
3– Smooth Muscle
1. Epithelial lining e.g. Skin, Digestive system
2. Secretary glands e.g. Salivary glands
Elastin - helps in stretching and recoil of the lungs
-Plasma (fluid portion of blood) and Interstitial fluid
(which surrounds the cells)
-when cold outside, our body temperature decreases than shivering occurs to increase the body temperature.
-supply of nutrient
-concentration of O2 and CO2
-waste product concentration
-pH as acidity affects enzyme activity
-concentration of water and electrolytes
- Temperature, narrow limit 35-38c
- plasma volume and Blood pressure
1. Circulatory system
2. Digestive system
3. Respiratory system
4. Urinary system
5. Skeletal system
6. Muscular system
7. Integumentary system- skin, hair, nails, sweat glands, temperature regulation
8. Immune system
9. Nervous system
10. Endocrine system
11. Reproductive system
1. Negative Feedback
2. Positive Feedback
1. If CO2 increases in the body, there will be respiratory stimulation which will try to wash out CO2 and bring it back to the normal. It is Negative Feedback mechanism.
2. If blood sugar decreases, body will try to increase blood sugar. It is Negative Feedback mechanism.
If temperature increases, Positive Feedback will increase it more.
Here hormone Oxytocin causes powerful contraction of uterus. As contraction push the baby against cervix (exit of the uterus), the resultant stretching of the cervix sends message to brain(posterior pituitary) and causes release of more Oxytocin, which causes even stronger uterine contractions. Positive Feedback does not stop until baby is born.
Cell – Tissue – Organs – System – Body
- Negative and Positive