SS2 Third Term Biology Lesson Note – Regulation of Internal Environment (Kidney)

The content is just an excerpt from the complete note for SS2 Third Term Biology Lesson Note – Regulation of Internal Environment (Kidney). Check below to download the complete DOCUMENT

WEEK 6                                                                                         

TOPIC: REGULATION OF INTERNAL ENVIRONMENT (KIDNEY)

 CONTENT:

1. Homeostatic Organs: substances involved in Homeostatis
2. The kidney (i) structure, functions and diseases of kidney (ii)the effects kidney diseases and remedy

SUB-TOPIC 1: HOMEOSTATIC ORGANS: SUBSTANCE INVOLVED IN HOMEOSTASIS

Homeostasis is the maintenance of a steady internal environment in an organism. Internal conditions such as glucose level, salt concentration, osmotic pressure, body temperature, ionic concentration of substances like sodium ion (Na⁺ ), potassium ion (K⁺) and hydrogen ion (H⁺) (and others like Ca²⁺, Cl^–) are kept under control.

For example, when glucose level in the blood shoot up above the optimum, homeostasis ensures that some of it is withdrawn from the blood and converted to glycogen which is stored in the liver and muscle. Another example is when there is insufficient (Ca²⁺) calcium ion in the diet of a pregnant woman, the homeostatic process can deplete from her bones as a last resort. That is why pregnant woman are advice to eat balance diet.

The process of homoestasis involves the detection of changes by sensory cells, signal is sent to the relevant body parts involved in the specific control mechanism. The central nervous systems interpret the signal and send message to the relevant effectors organs to restore normality in the internal environment. Thus, homeostasis involves monitoring changes in the external and internal environment by means of receptors and adjusting the composition the body fluids accordingly.

Limbic System

The limbic system is a group of brain structures that play a role in emotion, memory, and motivation. For example, electrical stimulation of the amygdala in laboratory animals can provoke fear, anger, and aggression. The hypothalamus regulates hunger, thirst, sleep, body temperature, sexual drive, and other functions.

Organs involved in Homeostasis

The organs involved in homeostasis control are mainly organs involved in some body functions such as excretion, respiration and glands. Excretion and osmo-regulation are important in the process; especially in the maintenance of acid-base balance and temperature of the body. The brain has the most overall influence on homeostasis.

Among the major organs involved in homeostasis are:

To gain full access to the note: DOWNLOAD FILE