BIOLOGY AND GEOLOGY3º DE E.S.O.

Chapter 4: THE INTERACTION

FUNCTION

1. The interaction function

http://www.edistribucion.es/anayaeducacion/8440042/U04_SC3/U04_00_INT_00_SC/04_Nuestra_funcion_relacion_ING.html

The interaction function

are perceived thanks to the

which send

The receptors

Stimuli

Messages to

The nervous system

Stimulus: any change that results in a change in the organism.

temperature, light, pressure, sound, smell, etc

The interaction function

The nervous system it produces

Responses

transmitted by

Nerve impulses

That are sent to

Effectors (muscles)

Response: any action resulting from a stimulus.

contraction of muscle cells

secretion by a gland

UNIT

4The interaction function

it produces

Responses

transmitted by

Hormones

through

Chemical reactions

that are sent to

Effectors (glands)

Response: any action resulting from a stimulus.

contraction of muscle cells

secretion by a gland

The nervous system

MUSCULAR RESPONSE

SECRETION RESPONSE

6. NERVOUS COORDINATION

This communication system controls and

coordinates functions throughout the body and responds to internal and

external stimuli.

6.1 NEURONS AND NERVOUS IMPULSE

A nerve is an organ containing a lot of nerve cells called neurons.

Neurons carry electrical messages called impulses throughout the body. Picture shows hundreds of

neuron axons

6.1 NEURONS AND NERVOUS IMPULSE

Each neuron Each neuron consists of:consists of:The cell body.The cell body.

Dendrites.Dendrites.

The axon. The axon.

Cell body consists of nucleusCell body consists of nucleus

Dendrites consist of nerve fibers that carry impulses toward Dendrites consist of nerve fibers that carry impulses toward the cell bodythe cell body

Axon is a single nerve fiber that carries impulses away Axon is a single nerve fiber that carries impulses away from the cell bodyfrom the cell body

6.1 NEURONS AND NERVOUS IMPULSE

Myelin covers the axon (fat covering) that insulates Myelin covers the axon (fat covering) that insulates and maintains the axonand maintains the axon

Nodes of Ranvier are areas where no myelin is presentNodes of Ranvier are areas where no myelin is present

6.1 NEURONS AND NERVOUS IMPULSE

6.1 NERVOUS IMPULSE TRANSMITION

Because neurons never touch, chemical signals called neurotransmitters must travel through the space called synapse between two neurons.

6.1 NERVOUS IMPULSE TRANSMITION

The axon of one neuron lies next The axon of one neuron lies next to the dendrites of another to the dendrites of another neuronneuron

The spaces between them are The spaces between them are called synapsescalled synapses

Impulses coming from one axon Impulses coming from one axon “jump” the synapse to get to the “jump” the synapse to get to the dendrite of another neuron which dendrite of another neuron which carry it in the right directioncarry it in the right direction

Special chemicals, Special chemicals, neurotransmitters, found at the neurotransmitters, found at the end of each neuron allow end of each neuron allow impulses to pass from one impulses to pass from one neuron to another so impulses neuron to another so impulses can follow many different routescan follow many different routes

6.1 NERVOUS IMPULSE TRANSMITION

6.2 THE NERVOUS SYSTEM

This communication system controls and

coordinates functions throughout the body and responds to internal and

external stimuli.

6.2 THE NERVOUS SYSTEM

There are two main parts:

Central nervous system (CNS): consists of

BrainSpinal cord

Peripheral nervous system (PNS): consists of

Nerves

http://www.youtube.com/watch?v=sjyI4CmBOA0

•The CNS is the control center of the body:•Receives information•Processes and coordinates information

•Elaborates responses

6.3 THE CENTRAL NERVOUS SYSTEM

6.3 THE CENTRAL NERVOUS SYSTEM

brain

Spinal Cord

Cerebellum

Cerebrum

Brain stem: Medulla Oblongata

Consists of: Brain and Spinal Cord

Cerebrum Voluntary or conscious activities of the body (learning, thinking)

Cerebellum Coordinates and balances the actions of the muscles and helps

us keep our balnce.

Brain stem: Medulla

Oblongata

Controls involuntary actions like blood pressure, heart rate, breathing, and swallowing

Spinal CordThe main communications link

between the brain and the rest of the body. Control reflexes

6.3 THE CENTRAL NERVOUS SYSTEM

Spinal Cord

• Links communication between the brain and the rest of the body

• 31 pairs of spinal nerves branch out from the spinal cord connecting brain to body

• Reflexes = quick, automatic responses to stimuli are processed directly in the spinal cord

6.3 THE CENTRAL NERVOUS SYSTEM

Spinal Cord

Receptors in the skin send information to the spinal cord through the spinal nerves. The nerve fibers enter the spinal cord through the sensory root. Some fibers make synapses with other neurons and continue up to the brain. After that the response travels through the motor root to muscles to control movement.

6.3 THE CENTRAL NERVOUS SYSTEM

6.4 Peripheral Nervous System• Consists of nerves and associated

cells that are not part of the brain or spinal cord

• Receives information from the environment and relays commands from the CNS to organs and glands

• Divided into two parts:• Sensory division: transmits impulses

from sense organs to the CNS• Motor division: transmits impulses from

the CNS to the muscles or glands

PNS animation (Pain receptor) : http://pennhealth.com/encyclopedia/em_DisplayAnimation.aspx?gcid=000054&ptid=17

Somatic System• Part of motor division that

regulates activities that are under conscious control (movement of skeletal muscles)

Autonomic System

• Part of the motor division that regulates activities that are automatic or involuntary (heart beat and smooth muscle in digestive system and blood vessels)

• Two parts that have opposite effects on the organs they control:• Sympathetic (“gas pedal”)• Parasympathetic (“brake”)

Sympathetic (“gas pedal”)Parasympathetic (“brake”)

Concept Map

which consists of

is divided into

that make up

which is divided into

The Nervous System

Sensory nerves

Motor nerves

Autonomic nervous system

Somatic nervous system

Central nervous system

Peripheral nervous system

Sympathetic nervous system

Parasympathetic nervous system

MAPA CONCEPTUAL

6.5 Reflex and voluntary actions

Reflexes (reflex action) = quick, automatic responses to stimuli are processed directly in the spinal cord

6.5.1 Reflex action6.5 How the nervous system works

6.5.1 Reflex arc• The pathway that an

impulse travels:• 1. from the sensory

receptor • 2. up the sensory

neuron • 3. over the synapse • 4. to the spinal cord

(interneuron) • 5. over another

synapse • 6. back down the

motor neuron • 7. to the effector

6.5.2 VOLUNTARY ACTIONS

8.1 The endocrine system

• Main Function:

It releases hormones into the blood to signal other cells to behave in certain ways. It is a slow form of communication.

8. The endocrine coordination

Endocrine glands Release hormones into the bloodstream.

Hormones are chemicals released in one part of the body that travel through the bloodstream and affect the activities of cells in other parts of the body.

Consists of:

8.1 The endocrine systemGLANDS

8.1 The endocrine system

https://www.youtube.com/watch?v=z-GXGR7AFpQ

The hypothalamus is located in the brain and controls the release of hormones from the pituitary gland. It is an important link between the endocrine and nervous systems.

8.2 How the endocrine system works?

http://www.youtube.com/watch?v=nNLsXKkLSTs

8.2 How the endocrine system works?

8.3 PITUITARY HORMONES DIAGRAM

8.3THYROID AND PARATHYROID DIAGRAM

• Functions: -The adrenal glands release Adrenaline in the body that helps prepare for and deal with stress.-Also regulates kidney function.

8.3 ADRENAL GLANDS

• Function: The Insulin and Glycogen in the Pancreas help to keep the level of glucose in the blood stable.

• Disorders: When the Pancreas fails to produce or properly use Insulin, it can cause a condition known as Diabetes Mellitus.

8.3 PANCREAS

• Functions:

• Pair of reproductive glands that produces sperm.

• Also secrete Testosterone to give the body its masculine characteristics.

8.3 TESTES

4,3 OVARIES • Functions:

• Pair of reproductive organs found in women that produce eggs.

• Also secrete estrogen and progesterone, which control ovulation and menstruation.