What is interaction?All living beings interact with their environmentand with other living beings to survive.Interaction enables livings beings to recieve andrespond to a stimulus.Interaction involves different elements...
Stimuli are... Detectable changes in the internal or external environment which provoke responses. They can be: Physical: light, sound, temperature... Chemical: substances like water, oxygen... Biotic: other living beings
Receptors are... Structures which receive stimuli from the external or internal environment. In animals, they are called sense organs.
How do receptors work ?Sense Sense organ How do they work?Sight Eyes They detect lightSmell Nose (vertebrates) They detect chemical substances dissolved in air or Appendage water (arthropods)Taste Tongue It detects chemical substances dissolved in water. It is covered with tiny taste buds.Hearing Ears They detect sound.Touch Skin (vertebrates) They detect pressure, touch, pain and temperature Appendage changes. (arthropods)
Activities 1. Test a classmate on sense organs. A: Which sense organ detects chemical substances in air? B: The nose.
Activities 2. Can you solve these sense organs riddles? This organ is used by... … arthropods to smell things. … fish to detect temperature changes. … most animals to detect pressure. … some animals to distinguish sounds.
How does coordination workin animals? Coordination involves processing information received from receptors and producing appropriate responses. Animals have two coordination systems: Nervous system Endocrine system
Nervous system The nervous system receives information, interprets it, and transmits a response to the responsive organs or effectors. It includes: The central nervous system. (CNS) This consists of the brain and the spinal cord. It analyses information and decides on a suitable response. The peripheral nervous system (PNS): carries nerve impulses from the nerve centres to all other parts of the body.
Activities Indicate which coordination system is working in each of these situations: Putting your hand close to a flame and then taking away quickly. Maintaining an adequate level of sugar in the blood. Stopping when a car comes when crossing the street.
How do the responsiveorgans work? There are two types of responses to stimuli: Motor responses: the response is movement Endocrine responses: response is the release of hormones
Motor responses invertebrates Motor responses are controlled by organs in the motor system, which consists of: Skeletal system (internal): bones supports the body. Muscular system: muscles are contractile organs attached to the bones by tendons.
Endocrine responses They are controlled by glands in the endocrine system. Glands produce chemical substances called hormones. Hormones: Are released into the blood. Control and coordinate activities throughout the body
Endoncrine system Both vertebrates and invertebrates have endocrine systems. It regulates functions which require maintained responses. These include: Metamorphosis of some animals Growth Production of milk in mammals Metabolism (chemical processes in living things that change food into energy and materials)
The pancreas The pancreas is a gland which controls insuline secretion in order to regulate glucose levels in the blood.
Activities Are these statements true or false? Only vertebrates possess an endocrine system Hormones are transported in the blood. The pancreas is part of the motor system. Responses from the endocrine system are immediate and rapid.
Activities Are the following responses controlled by the nervous system or the endocrine system? A child growing up A dog chasing a cat A cow producing milk Dancing to music A tadpole changing to a frog
Complete the chart: Nervous system Endocrine systemTransmission by N_______ B______Means of transmission Nerve impulses Hor______Speed of response Rapid Sl___Duration of response Brief Lo___Regulation and coordination Functions which require Functions which requireof functions r____ responses, such a ma_______ed responses locomotion such as g____, dev____ent, metab_____.
Glossary Living being Environment Receive Respond Stimuli Receptor Effector Sight Smell Taste Touch Sense organs Chemical substances Pressure Nervous system Brain Spinal cord Motor responses Skeletal system Glands (produce hormones) Growth Mammals Blood Metabolism