AQA Biology - Unit One - The Human Body (Part 1/4)

Unit One Biology

The Human Body (P1/4)

 Introduction

Welcome to this 4 part series intending to give you all the information you need through Unit One of AQA biology.

Part One - Human Body

Part Two - Healthy Bodies

Part Three - Evolution

Part Four - Genetics/Human's and the Enviroment 

Parts of Nervous System

CNS - Brain, Spinal Cord. This is the where relay nurones are found, and this is where the electrical impules from a sensory neurone is processed.

Sensory Neurone - Connects from a receptor (i.e Eyes), and travels TOWARDS the CNS. 

Relay Neurone - Found in the CNS, and these are neurones which connect Sensory and motor Neurone.

Motor Neurone - Travels AWAY from the CNS, connects to an effector, (i.e Muscles)

Synapse - The gap in-between the neurones. 

The Synapse

Synapse -

 The gap in-between the neurones. 

An electrical Impulse arrives from a neurone and this stimulates bubble of chemical to pop. The neurone transmitter chemicals then diffuse across the gap, and stimulate an electrical impulse on the next neurone. This means the pulse can only travel one way.

Internal Conditions 

Temperature - 37 Degree's C. This is the best temperature at which body enzymes work best. 

Water - Most of the body is made of water, and is lost through Urine, and breathing. And gained through food and drinking. 

Ion Content - Salt and Potassium. Needed to make some body proteins. Controlled through Sweat, Urine, and gained through eating and drinking.

Blood Sugar - Sugar is needed for chemical respiration in body cells (for energy), to high levels can lead to diabetes. Controlled through eating and drinking. And level of exercise. 

Hormones and Fertility 

Hormones control many different aspects and process…