HUMAN RESPONSES TO THE ENVIRONMENT Two systems to be studied: 1.Nervous system 2.Endocrine system
Introduction To survive all organisms have to react to changes in their external and internal environment External environment: Environment outside the body for example of factors that might change are temperature, light, etc in their natural environment or habitat. Internal environment: Environment inside the body e.g. concentration of CO 2, O 2, H 2 O around cells/tissues/organs inside the body.
Introduction (cont.) Human response to these changes in the environment occurs to maintain stability/balance within the organism. Organisms sense changes in the environment as a stimulus. These impulses are send to the brain which interpret the information and sends a different message back to the part of the body telling it how to react.
Homeostasis The body works hard to keep its internal environment as constant as possible. All the organs and systems of the body work together to create this stable internal condition. The process of maintaining a constant cell environment in the body is called homeostasis. The endocrine and nervous systems, as our co-ordinating systems, play a very important part in regulating homeostasis. Examples: Blood pressure, glucose levels in the blood, ect.
Human Nervous system - What to learn: Structure of 3 types of neurons, nerve bundles, transmission of an impulse (Making of drawings) CNS, Peripheral, Autonomic (sympathetic & parasympathetic), disorders Difference between reflex arc and reflex action Structure (making of drawings) and functioning of a simple arc, Significance of a reflex arc Sense organs (Ear and Eye) - Drawings
Co-ordination in Humans Nervous co-ordination Chemical co-ordination Central nervous system Peripheral and autonomic nervous systems Sense receptors and organs Endocrine system Feedback mechanisms Over- & under- secretion
Human nervous system is a complex system
Cross-section of the human brain showing the different parts
Functions of certain parts of the brain Cerebellum Co-ordinates movements of your voluntary muscles Maintains your balance by controlling muscle tension
Functions of certain parts of the brain Hypothalamus Controls your blood pressure Controls your body temperature Regulates your levels of thirst and hunger Regulates emotions such as anger and pleasure Regulates your sleep patterns (Control centre for homeostasis)
Functions of certain parts of the brain Cerebrum Controls all voluntary muscle actions Receives and interpret sensations of sight, hearing, taste, smell, touch and speech Responsible for higher thought processes such as memory, reasoning, judgement and intelligence Responsible for behaviour and emotions
Functions of certain parts of the brain Medulla oblongata (same structure as the spinal cord) Controls important involuntary actions such as heartbeat and breathing Enables each half of your brain to control the opposite side of your body Transmit nerve impulses between the spinal cord and the brain
Functions of certain parts of the brain Spinal cord Links the brain with all the organs of the body (except those in the head & neck) Carries sensory information to the brain for interpretation Carriers then motor information from the brain to the effectors (muscles and glands) Its a centre for the reflex action, which enables the body to respond very quickly to harmful stimuli using the reflex arc
A typical nerve cell A NEURON
INJURED NERVEAGING BRAIN
LEARNER ACTIVITIES Label brain, spinal cord and neuron diagrams Practical using sheep brain, slides Table of parts and function of all the above Describe reflex action using a diagram as a guide and give significance Group work : effect of drugs on CNS- presentation Write short notes on Alzheimers Disease and Attention Deficit Disorder
EYE Structure of eye and function of parts.- 1 lesson Formation of an image,Binocular vision -1 lesson Accomodation-,Pupillary mechanism -1 lesson Disorders homework 1 lesson
LEARNER ACTIVITIES PRACTICAL demonstrate blind spot, dissect eye of sheep, pig etc Label diagram of human eye. List functions of parts of eye Using diagrams describe in writing formation of an image,accomodation, binocular vision,pupillary mechanism Homework- notes on long and short sightedness, astigmatism,cataracts
EAR Structure and functions of parts of ear,adaptations of parts of ear 1 lesson Hearing and balance 1 lesson Hearing defects(infections and deafness)-1 lesson Link deafness and speech disorders,Sign language,Attitudes to deaf and blind,Rights of deaf and blind 1 lesson
LEARNER ACTIVITIES Label diagram of ear Write notes on adaptions of parts of an ear(homework and feedback) Describe hearing and balance functioning of ear in writing ( open book after explanation by teacher) Cause and treatment of disorders homework Discussion on attitudes,sign language,rights of blind and deaf
DIAGRAMS OF EAR
HUMAN ENDOCRINE SYSTEM Definition of chemical coordination,differences between endo and axo crine glands,characteristics of hormones (30 minutes) Location and functions of hormones,negative feedback ( 1.5 lessons) Disorders: diabetes,hypo/hyper thyroidism,growth disorders, infertility (homework/feedback 1 lesson)