Control and

coordination
BIOLOGY
Biology is the study of life.

In 3 basis the organisms were studied.

• Morphology
• Anatomy
• physiology
morphology
anatomy
Physiology
anatomy&
physiology
 MOVEMENT IN ORGANISMS
The ability of organisms to move certain body parts is movement.
When they move from one place to another, it is called locomotion. Organisms show
movements in response to stimuli.
INTRODUCTION
Organisms move in response to various kinds of stimuli like light,
heat, nutrients/food, etc.
All the activities in animals are controlled and coordinated by the
nervous and endocrine system.
Hormones are chemical messengers, which assist the nervous system
in carrying out various functions. They are secreted by endocrine
glands.
Hormones in plants coordinate the movements.
Nervous system
Nervous System
• The nervous system or the neural system is a complex
network of neurons specialized to carry messages. The
complexity of the nervous system increases as we move
towards higher animals.
• For instance, cnidarians such as jellyfish have relatively
simple nerve nets spread throughout their body. Crabs have a
more complicated nervous system in the form of 2 nerve
centers called dorsal ganglion and ventral ganglion.
Nervous System
• As we move further up the ladder, higher organisms such as
vertebrates have a developed brain. Moreover, it is one of the most
complicated structures in the animal kingdom, containing billions of
neurons, all intricately connected.
• In the human body, the neural system integrates the activities of organs
based on the stimuli, which the neurons detect and transmit. They
transmit messages in the form of electrical impulses and convey
messages to and from the sense organs. Thus, the nervous coordination
involves the participation of the sense organs, nerves, spinal cord, and
brain.
Central Nervous System
• Central Nervous System (CNS) is often called the central processing unit of the
body. It consists of the brain and the spinal cord.
Brain
• The brain is one of the important, largest and central organ of the human nervous
system. It is the control unit of the nervous system, which helps us in discovering
new things, remembering and understanding, making decisions, and a lot more. It
is enclosed within the skull, which provides frontal, lateral and dorsal
protection. The human brain is composed of three major parts:
• Forebrain: The anterior part of the brain, consists of Cerebrum, Hypothalamus
and Thalamus.
• Midbrain: The smaller and central part of the brainstem, consists of Tectum and
Tegmentum.
• Hindbrain: The central region of the brain, composed of Cerebellum, Medulla
and Pons.
Central Nervous System
Spinal Cord
The spinal cord is a cylindrical bundle of nerve fibers and associated
tissues enclosed within the spine and connect all parts of the body to
the brain.
It begins in continuation with the medulla and extends downwards. It
is enclosed in a bony cage called vertebral column and surrounded by
membranes called meninges.
The spinal cord is concerned with spinal reflex actions and the
conduction of nerve impulses to and from the brain.
PERIPHERAL NERVOUS SYSTEM
Peripheral Nervous System (PNS) is the lateral part of the nervous
system that develops from the central nervous system which connects
different parts of the body with the CNS. We carry out both voluntary
and involuntary actions with the help of peripheral nerves.
• PNS includes two types of nerve fibers:
• Afferent nerve fibers – These are responsible for transmitting
messages from tissues and organs to the CNS.
• Efferent nerve-fibers – These are responsible for conveying
messages from CNS to the corresponding peripheral organ.
 PERIPHERAL NERVOUS SYSTEM
Classification of the peripheral nervous system:
• Somatic neural system (SNS): It is the neural system that controls the voluntary
actions in the body by transmitting impulses from CNS to skeletal muscle cells. It
consists of the somatic nerves.
• Autonomic neural system (ANS): The autonomic neural system is involved in
involuntary actions like regulation of physiological functions (digestion, respiration,
salivation, etc.). It is a self-regulating system which conveys the impulses from the
CNS to the smooth muscles and involuntary organs (heart, bladder and pupil). The
autonomic neural system can be further divided into:
Sympathetic nervous system
Parasympathetic nervous system
Neuron
• A Neuron is a structured and functional unit of the nervous system and
unlike other cells, neurons are irregular in shape and able to conduct
electrochemical signals. The different parts of a neuron are discussed below.
• Dendrite stretches out from the cell body of a neuron, and it is the shortest
fibre in the cell body.
• Axon is the longest thread on the cell body of a neuron and has an
insulating and protective sheath of myelin around it.
• Cell body consists of cytoplasm and nucleus.
• Synapse is the microscopic gap between a pair of adjacent neurons over
which nerve impulses pass, when moving from one neuron to the other.
 Neuron
Neuron is the structural and functional unit of the nervous system.
•Each neuron has three main parts: dendrites, cyton/soma/cell body
and axon.
•Dendrites receive impulses from other neurons.
•Cyton/soma processes the impulse.
•Axon transmits the impulse, either to another neuron or to
muscles/glands, etc.
•Axon may be myelinated or non-myelinated.
•The impulse transmission is faster in myelinated neurons.
Nerves
• Nerves are thread-like structures that emerge from the brain and spinal
cord. It is responsible for carrying messages to all the parts of the
body. There are three types of nerves. Some of these neurons can fire
signals at speeds of over 119 m/s or above 428 km/h.
• Sensory nerves send messages from all the senses to the brain.
• Motor nerves carry messages from the brain to all the muscles.
• Mixed nerves carry both sensory and motor nerves.
Nerves
• Cranial nerves begin from the brain as these nerves carry impulses to
start from the central nervous system. Certain cranial nerves belong
to the group of mixed nerves while certain ones fall under sensory
nerves. Spinal nerves originate from the spinal cord. All the spinal
nerves carry impulses to and from the central nervous system and
these are part of mixed nerves.
• Learn more in detail about the Human Nervous System, its structure,
functions, different parts and their disorders or any other related
topics by referring to the nervous system notes provided at BYJU’S
website. Download BYJU’S app for further reference.
HORMONAL SYSTEM IN ANIMALS
Electrical impulses are excellent means for transmission of information but there
are few limitations of using electrical impulses-
Impulses reach only those cells that are connected with nervous tissue.
Cells cannot continuously create and transmit impulse, the cells need some time to
reset the mechanism before these can create and generate a new impulse.
Due the limitations, instead of generating electrical impulse, the stimulated cells
release a chemical compound called hormones.
Hormones will diffuse to all the cells of the body and the cells have receptors to
detect the hormones and to receive the information and transmit it.
Hormones are the chemical messengers which are secreted by the endocrine gland
into the blood.
 Different animal hormones
Thyroxin hormone
Secreted by thyroid gland with the use
of iodine.
Helps in the regulation of
carbohydrates, proteins and fat
metabolism in the body.
Deficiency of the hormone
causes goitre.
Enlargedneck is the characteristic
symptom of goitre.
Growth hormone
Secreted by pituitary
gland.
Regulates growth and
development of the body.
Deficiency of the
hormone leads
to dwarfism.
Over production causes
Gigantism
 Sex hormones
• Gonads are the gamete-producing organs –
testes in males and ovaries in females.
• The testes produce the male hormone
testosterone and ovaries produce the female
hormones oestrogen and progesterone.
• Testosterone and oestrogen help in producing
gametes and are responsible for the sexual
characteristics in males and females
respectively.
• Progesterone is the pregnancy hormone.
• ANDROGEN – MALE CHARECTERS
• OESTROGEN–FEMALE CHARECTERS
 Insulin
• Secreted by pancreas.
• Regulates blood sugar
level.
• Deficiency of the
hormone causes diabetes
mellitus, increase in
blood sugar level.
Adrenal gland
• Occurs in pair above each
kidney.
• It decreases in size with
age.
• Secrets the hormone
adrenaline which helps in
flight and fight response.
Plant Hormones and Movements
Plant hormones
• Control and coordination in plants are carried out by hormones.

Plant Hormone Function

Auxin Helps in Growth of Plant Tissue
Cytokinin Promotes Cell division, delays aging of cells
Helps in growth of stems, initiates seed
Gibberilins germination, promotes flowering, cell division
and seed growth after germination
Inhibits growth and causes wilting of leaves,
Abscisic acid
promotes dormancy of buds and seeds
This is a gaseous hormone which causes
Ethylene
ripening of fruits
Any plants
can
Move….???? ?
YES,
ALL the plants can move.
But
the movements
were limited
Growth independent movements
• The movements which are not growth related are called nastic movements.
These movements occur in response to environmental stimuli but the
direction of response is not dependent on the direction of the stimulus.
• The movement in the touch-me-not plant is thigmonastic movement
(movement in response to touch).

Growth-related movements in plants

• The movements which are growth related are called tropic movements.
These movements occur in response to environmental stimuli and the
direction of the response is dependent on the direction of the stimulus.
Examples:

•Phototropic movement (light dependent)

•Geotropic movement (gravity dependent)
•Chemotropic movement (chemical dependent)
•Hydrotropic movement (water dependent)
•Thigmotropic movement (touch dependent)
DIAGRAMS
• HUMAN DIGESTIVE SYSTEM
• HUMAN RESPIRATORY SYSTEM
• STOMATA AND ALVEOLI
• HUMAN HEART L.S
• HUMAN EXCRETORY SYSTEM
• NEPHRONS