Page 14 - SAAT BIOLOGY PART 2

SAAT BIOLOGY MR.MOHAMED ELGAYAR MRPROF.NET
▪ Nervous System:

• Neurons are composed of dendrites, cell body that has the

nucleus, and the axon that is covered with a lipid called

myelin, greatly increasing the speed of the impulse as it

travels the length of the axon.

• Reflex arc: is a nerve pathway that consists of a sensory

neuron, an interneuron, and a motor neuron.

• Threshold: the minimum stimulus to cause an action

potential to be produced.

▪ Nervous System

▪ Centeral Nervous System:

Consists of: brain and spinal cord hypothalamus, medulla

oblongata, and pons. - The brain consists of cerebrum,

cerebellum

Cerebrum: largest part of the brain, and is divided into two

halves called hemispheres.

MRPROF.NET MR.MOHAMED ELGAYAR MRPROF.NET@GMAIL.COM