The nervous & endocrine system - bio-psychology

what is the nervous system

this consists of the central nervous system and the peripheral nervous system communicates using electrical signals

this is our primary internal comunnication singla

what are the division of the nervous system

what is the function of the nervous system ?

to collect, process and to respond to information in the environment

to co-ordinate the working of different organs and cells in the body

what are the two subsections the nervous system is divided into

the central nervous system

peripheral system

what is the CNS made up of ?

made up of the brain and spinal cord

what is the function of the brain ?

the brain is the centre of all conscious awareness

the brains outer layer the cerebral cortex = 3mm thick + covers brain like an orange peel -

highly developed in humans and is what distinguishes our higher mental functions from those of other mammals

what is the function of the spinal cord ?

it is an extension of the brain

it passes messages to and from the brain

connects nerves too the PNS

it is also responsible for reflex actions such as puling hand away from hot plate

describe the nervous system

what is the peripheral nervous system ?

sends information to the CNS from the outside world, and transmits messages from the CNS to muscles and glands in the body

they transmit messages via millions of neurons to and from the cns

it is further split into the autonomic and somatic nervous system

what is the somatic nervous system ?

transmits information from receptor cells in the sense organs to the CNS

it receives information from the CNS that directs muscle to act

governs muscle movement and receives info from sensory receptors -voluntary muscle movement occur

what is the autonomic nervous system ?

transmits info to and from internal bodily organs.

operate involuntary

has two main divisions the sympathetic and parasympathetic

controls:

breathing

hr

digestion

sexual arousal

stress response

what does the sympathetic system do

the branch concerned with expending energy - fight / flight response

what does the parasympathetic system do

concerned with conserving energy ( the natural resting state)

i.e. reduces hr

causes digestion to continue to take place

speed of nervous system compared to endocrine

the nervous system acts more rapidly than the endocrine system but they are both very fast

average response is 0.25s but can be as quick as 100 milliseconds

endocrine response is slower because hormones have to travel through the blood stream

what is the endocrine system ?

one of body’s major information systems that instructs glands to release hormones directly into the blood stream.

these hormones are carried towards target organs in the body communicates via chemicals

what does the endocrine system consist of ? and what does it do

it consists of glands that produce hormones which are released into the blood stream to be taken all over the body

hormones act slower than the nervous system but can take their messages over a much wider area

label the glands

1) hypothalamus

2) pituitary gland

3) thyroid

4)parathyroid

5) adrenal gland

6) pancreas

7) ovaries

8) testes

how do most hormones work use thyroid - throxine as a en example

most hormones affect cells in more than one body organ, leading to a diverse and powerful response

i.e. thyroid produces the hormone thyroxine - this effects cells in the heart and also increase the body’s metabolic rate in turn effecting growth rate

what is the pituitary gland

located in the brain

known as the master gland because it controls the releases of hormones from all the other endocrine glands in the body

explain how the autonomic system and endocrime system work together when

1. when stressors = perceived - hypothalamus activates the pituitary gland

2. this triggers activity in the sympathetic branch of the autonomic nervous system

3. the ANS changes from its normal resting state parasympathetic to the sympathetic state

4. adrenaline is then released from the adrenal medulla into the blood stream

5. this triggers physiological changes in the body(increased HR)-creates the necessary physical arousal for F&F

6. Once the threat is over the parasympathetic nervous system returns the body to resting state

what is the most important thing about the fight&flight response

that it all happens in an instant as soon as the threat is detected

an acute automatic reaction in the body

what are the main physiological changes associated with the sympathetic state

• increased HR

• increased breathing rate

• dilates pupil

• inhibits digestion

• inhibits saliva production

• contracts rectum

what are the physiological behaviours associated with the parasympathetic state

• decreased HR

• decreased breathing rate

• contraction of pupils

• stimulates digestion

• stimulates saliva production

• relaxes rectum

what is adrenaline

a hormone produced by the adrenal glands which is part of the human body’s immediate stress response system

what physiological changes are associated with adrenaline

contracting blood vessels

dilating air passages

stimulating heart rate

huge effects on the cells in the cardio vascular systems

what is the fight /7 flight response

the way animals respond when stressed

the body becomes physiologically aroused in readiness to fight an aggressor or flee

what is the endocrine system ?

one of the body’s major information systems that instructs glands to release hormones directly into the blood stream

hormones are carried towards target organs