CHAPTER 7 Control and Coordination. Control and Coordination The Nervous System.
Control & coordination
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Transcript of Control & coordination
CONTROL & COORDINATION
NEURON
GROUP ACTIVITY
Group ADefine Neuron
Group BCompare gustatory receptors and olfactory receptors
Group CIdentify the transmission of energy taking place in
nerve impulse conduction.
REFLEX ACTION
• When the stimulation of a receptor results in a spontaneous, involuntary reaction, it is called reflex action or simply reflex.
SPINAL REFLEX ACTION• The reflexes of this type which involve only the
spinal cord are called spinal reflexes. • Please note that when we lift a hot plate, then
along with heat, the pain produced by heat also acts as a 'stimulus'.
• Most of the reflex actions involve only the spinal cord. They are called spinal reflexes.
BRAIN REFLEX ACTION• Reflex actions which involve brain are called
cerebral reflexes. • Cerebral reflexes occur in the organs present in the
head because these organs are directly connected to the brain.
• Example. Our eyes are present in the head. In dim light, the pupil (a hole in the front of eye) is large so that more light can enter into the eye and make us see properly even in dim light.
Reflex arc
• Rather than think about the sensation of heat if the nerves detect heat were to be connected to the nerves that move muscles in a simpler way, the process of detecting the signal or the input and responding to it by an output action might be completed quickly. Such connections commonly called as reflex arc.
Group activity• Group A• Define reflex action.
• Group B• Components of reflex action.
• Group C• Discuss the process of reflex action.
Part I:
Lobes, the Cerebral Cortex, and Cortical Regions of the Brain
Cerebrum -The largest division of the brain. It is divided into two hemispheres, each of which is divided into four lobes.
Cerebrum Cerebrum
Cerebellum
http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif
Cerebral Cortex
Cerebral Cortex
Cerebral Cortex - The outermost layer of gray matter making up the superficial aspect of the cerebrum.
http://www.bioon.com/book/biology/whole/image/1/1-6.tif.jpg
Lobes of the Brain (4)
• Frontal• Parietal• Occipital• Temporal
http://www.bioon.com/book/biology/whole/image/1/1-8.tif.jpg
Lobes of the Brain - Frontal• The Frontal Lobe of the brain is located deep to the
Frontal Bone of the skull.
• It plays an integral role in the following functions/actions:
- Memory Formation- Emotions
- Decision Making/Reasoning - Personality
Modified from: http://www.bioon.com/book/biology/whole/image/1/1-8.tif.jpg
Lobes of the Brain - Parietal Lobe
• The Parietal Lobe of the brain is located deep to the Parietal Bone of the skull.
• It plays a major role in the following functions/actions:
- Senses and integrates sensation(s)
- Spatial awareness and perception(Proprioception - Awareness of body/ body parts in space and in relation to each other)
Lobes of the Brain – Temporal Lobe
• The Temporal Lobes are located on the sides of the brain, deep to the Temporal Bones of the skull.
• They play an integral role in the following functions:
- Hearing- Organization/Comprehension of
language
- Information Retrieval (Memory and Memory Formation)
Modified from: http://www.bioon.com/book/biology/whole/image/1/1-8.tif.jpg
Lobes and Structures of the Brain
B. A.
C.
D. E.
F.
G.
http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif
Group activity
• Group A• What do you mean by CNS? • Group B• Give the components of peripheral nervous
system.• Group C• Distinguish between voluntary and involuntary
action.
Brain has 3 regions• Fore- Brain - cerebrum, thalamus, and
hypothalamus (part of the limbic system).
• Mid-brain - The midbrain consists of the tectum and tegmentum.
• Hind-brain - cerebellum, pons and medulla. Often the midbrain, pons, and medulla are referred to together as the brainstem.
Fore- brain• The forebrain is divided into 2 halves – the right and
left cerebral hemispheres. • The cerebral hemispheres control your movement,
thinking, memory, emotions, senses and speech.• As the nerve fibres leave the brain, they cross over
from one side to the other.• This means that the nerves that come from the
right side of your brain control the left side of your body.
• Each hemisphere is divided into 4 areas called the
• Frontal lobe• Temporal lobe• Parietal lobe• Occipital lobe
• The frontal lobe contains areas that control your personality, thought, memory and behaviour.
• Towards the back of the frontal lobe are areas that control movement and feeling.
• The temporal lobe helps to control behaviour, memory, hearing, sight and your emotions.
• The parietal lobe is mainly to do with language. It is responsible for your speech, reading, writing or understanding of words.
• The occipital lobe is the visual centre of the brain.
Functions • Cerebellum - This structure is associated with
regulation and coordination of movement, posture, and balance.
• Brain Stem: This structure is responsible for basic vital life functions such as breathing, heartbeat, and blood pressure.
How brain tissues are protected?• The brain is protected by a series of bone, membrane,
and fluid. • The outermost protection is the cranium, or skull, which
protects the brain from blows that could easily damage it.
• Then there are three membranes called meninges. • Then brain is protected by a clear liquid called
cerebrospinal fluid. This forms a cushion between the soft brain tissue and the hard cranial bones. This same fluid also fills spaces inside the brain.
• Tissues inside the spaces produce cerebrospinal fluid, which flow through the spaces between the membranes.
Coordination in plants• Chhui mui or touch- me -not plant or sensitive plant• Mimosa family
Two different types of movement in plants
• 1. Growth dependent movement• 2. Growth independent movement
Immediate response to stimulus
• Immediate response ……• No nervous tissues/ muscle tissues involved in plant
body.• Plants undergo cell to cell communication system
different from nervous system and muscular system in animals.
• They use chemical signals followed by cells swelling due to uptake of more water and shrinking of cells due to loss of water from plant cells. So the cell shapes change due to response.
• Movement due to growth• Tendrils are plants that climb up on other plants or
fences.
• When tendrils come in contact with any support, the part of
• Tendril which is in contact with object does not grow as rapidly as away from the object or support. THIS MAKES TENDRILS TO CLING OR COIL AROUND SUPPORT.
• Environmental triggers such as light, or gravity will change in the directions that plant parts grow in.
Hydrotropism in plants
Plant hormones
• 1 . AUXIN - cell growth in shoot / root tip. • 2. GIBBERELLINS - cell growth in stems.• 3. CYTOKININS - cell division (dividing cells)• 4. ABSCISIC ACID - inhibits (stops) growth, wilt
leaves.
Phototropism with auxin hormone
The endocrine systemHormones :A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required. It is a chemical messenger that transports a signal from one cell to another.Hormones –secreted by ductless glands. Directly secreted into blood and lymph.
Endocrine system
Hormones are produced and secreted by
glands in the endocrine system.
It consists of various endocrine glands.
These glands do not have ducts (tubes)
for transporting chemical signals from
one part of the body to another. So, they
are referred as DUCTLESS GLANDS.
Target organs: The organs responds to
hormones.
Hormone producing glands and their secretions
Gland Location Secretion Function
Thyroid Neck Thyroxin Controls metabolic rate
Adrenal Above kidneys
Adrenalin Prepares body for emergency.
Pancreas Abdomen Insulin, glucagon
Regulates sugar level in blood.
Testes Lower abdomen (male)
Testosterone Controls sexual development.
Ovaries Lower abdomen (female)
Oestrogen Controls sexual development.
Pituitary Brain Growth hormone stimulating hormones
Speeds up growth, activates other glands.