Year 9 Science Body Balance Student Notes PDF

Year 9 Science What are some systems in our bodies that helps it maintain BALANCE? Body Balance – Nervous System Learning Intention Success Criteria Students understand the role of the I can describe the different parts and nervous system in controlling how role...

Year 9 Science What are some systems in our bodies that helps it maintain BALANCE? Body Balance – Nervous System Learning Intention Success Criteria Students understand the role of the I can describe the different parts and nervous system in controlling how roles of the central nervous system the body receives and responses I can describe the role of the to stimulus. Peripheral nervous system Students understand the different I can explain how the CNS and the PNS parts of the nervous system and work together in the body the different roles they play. What if we could look inside human brains? Or click here.  The nervous system consists of the _______, __________ and ____________ that run throughout your body. Messages sent by these nerves are called nerve impulses and they travel VERY quickly. The brain is the _________ ____________ of your body and has nerve connections which reach throughout it.  Cerebrum: largest part of the brain and controls memory, speech and conscious thought controls senses such as taste, hearing, sight, touch and smell controls actions such as running and walking each of these actions are ______________ as you can control them by thinking about them  Cerebellum (little brain) small part of the brain behind the cerebellum coordinates muscle activity without you thinking about it (________________ actions) as an example, it controls balance and coordinates muscle movement  Brain stem at the base of the brain and is responsible for other _______________ actions examples include breathing, heartbeat and digestion, swallowing, body temperature Uncovering the brain's biggest secret What does this video make you wonder about? What do you think the video is trying to show or teach us? What surprised you in the video? Why? Or click here. Year 9 Science  The nervous system is made up of two Brain parts: The __________ ____________ __________ consists of the brain and spinal cord. It's sometimes called the "coordinator" because it makes sense of the messages it receives from the sense organs and coordinates responses by the muscles and glands. Spinal cord What are the ‘sense organs’?  Brain and spinal Nerves running between the cord only. central nervous system, muscles and other sense organs. The _________________ ______________ ___________ consists of the bundles of nerves that relay messages between the sense organs, the central nervous system and the muscles and glands. This system is spread out through the entire body. Think of the central nervous system as the head coach of a sport team who instructs their players – the peripheral nervous system – who act according to the coach’s message. Body Balance – Nervous System Learning Intention Success Criteria Students understand the role of the I can describe how receptors in our nervous system in controlling how body detects and receives signals the body receives and responses (stimuli) to stimulus. I can explain how receptors pass the Students understand the different message through neurons (nerve parts of the nervous system and cells) the different roles they play. I can explain how the stimulus response model works  _______________ are cells that Receptors can detect stimuli such as: allow us to detect different types Temperature of stimuli. Thirst changes Stimuli induce responses which produce effects. Flavours Thinking about the same sport team, the receptors can be thought of as the player’s ears. The message that Sights (vision) the players here from their coach is heard and they Pain respond in certain ways depending on what message they receive. Objects Odours  ________ _________________ are sensitive to chemical changes in damaged cells and are located throughout the body, but most are located in the skin. ______________ are sensitive to ___________________ are sensitive to temperature changes and are chemicals, such as odour molecules in the air, located in the skin. and are located in the nose and tongue. ______________________ are sensitive to touch, pressure, sound and _______________ are sensitive to motion and are located in the skin, the light and are located in the eyes. inner ear and muscles. Sensory Receptors The table below lists the sensory receptors in the human body and the stimuli they detect. Receptor Stimuli Detected Rods and cones in eye Cells in cochlear (inner ear) Skin (many receptors) Around hairs in skin Taste buds in tongue Olfactory cells in nose  _______________ are specialised cells that transmit messages, in the form of ______________ ______________, to and from, and within, the central nervous system. They act like the wires of an electric circuit. ______________ neurons transmit ________________ transmit messages messages from receptors to the from sensory neurons to motor neurons. central nervous system. _____________ neurons transmit messages from the central nervous system to "effectors" such as muscles and glands to initiate a response. This is an example of how a stimulus (in this case, the sight of an object) can be used to trigger a response which in this case is muscle movement which enables drinking of the water. What about….. - Eating a sour lemon - Kicking your toe  Neurons generally have the same structure. They are made up of: _______________ - branches that receive electrical messages, a _______________ - where organelles such as the nucleus are found ______________ - transmit a message away from the cell body ______________ - a fatty layer that insulates the axon  Neurons meet at a _____________ The axon of the first neuron (pre- synaptic) carries the signal across the synapse to a dendrite of the next neuron (post-synaptic) cell. Neurotransmitters are responsible for carrying the signal across the synapse to the next neuron. They are detected by receptors. Different neurotransmitters are used for different responses. Signal direction Neurotransmitters: - Adrenaline - Noradrenaline - Dopamine - Serotonin - Gaba - Acetylcholine - Glutamate - Endorphins Signal direction Sensory Neurons There are two types of neurons – __________ neurons and ___________ neurons. Sensory neurons send nerve impulses to the brain from the body’s receptors. These receptors are attached to one end of the neuron, and detect external stimuli such as light and sound, or internal stimuli such as the level of carbon dioxide in the blood or the fullness of your bladder. Motor Neurons The ________ from the __________ neurons are received by the brain or spinal cord. Other impulses are sent out along the motor neurons to ________ or ___________.  Reflex responses are _____ coordinated by the ___________ but they involve shortcuts from the sensory neuron to the spinal cord and directly to a motor neuron which leads to a muscle. Reflex responses are very fast and are _______________ as the brain does not Brain is not involved, just the spinal cord! coordinate them. Examples of reflex responses include: blinking to protect your eyes from objects moving your arm away very quickly from a hot pan to avoid damage To research…(15mins) Write your answers on OneNote What is a neuron? Draw 2 neurons connecting together and label the parts of a neuron: Dendrites, cell body, axon, myelin sheath, neurotransmitter, synapse, axon ending Give a short description of each part. What are receptors? How do they work on neurons? What are some examples of receptors and their functions? What are the parts of the neuron? How many types of neurons are there? What is the purpose of the neuron? Body Balance – Endocrine System Learning Intention Success Criteria Students understand the role of the I can describe the roles of the nervous system in controlling how endocrine system the body receives and responses I can explain how the endocrine to stimulus. system functions through chemical Students understand the different messengers (hormones) parts of the nervous system and the different roles they play. Students understand how negative feedback operates in the nervous system.  Consists of a number of throughout the body. These glands produce messengers called ______________ Hormones travel throughout the body using the Longer lasting response than nervous signal Slower response than nervous signal  There are many different endocrine glands that ____________ (release) different hormones. Each specific hormone has one or more specific ___________ The ___________ __________ is said to be the master gland as it controls other endocrine glands. It is also responsible for regulating sex hormones, puberty and metabolism.  Hormones enter the blood stream and navigate it to locate their target cell. The target cell has a receptor on it which recognises a specific hormone. The hormone must be the right ____________ to fit the receptor. Activity of the cell changes. Hormone Hormone released binds receptor  Depending on the hormone, they can act on the whole body or a specific organ. Nerves only act on muscles and glands (like sweat glands) Hormone Hormone released binds receptor Endocrine Gland Circulatory System Target cell activity altered  Depending on the hormone, they can act on the whole body or a specific organ. Nerves only act on muscles and glands (like sweat glands) System Property Endocrine Nervous Signal used Origin of signal Sent by Speed of transmission Target Effects Duration  Some hormones, their targets and functions… Hormone Secreted by Target cells Function Thyroxine makes cells consume more oxygen and nutrients increases body temperature by increasing metabolic rate Adrenaline increases heart rate shuts down digestion makes energy available to muscles fight or flight Testosterone Testes Testes, bone, muscle, other stimulates the growth of facial and body hair sex characteristic tissues muscle and bone strength Oestrogen Ovaries Ovaries, fat tissue, and other stimulates the growth of body hair sex characteristic tissues growth of fat cells under the skin development of breasts Follicle-stimulating Pituitary gland Gonads (ovaries and testes) stimulates egg production in females hormone stimulates sperm production in males How are the 2 systems connected? The nervous system and the endocrine system are connected because they both help control and coordinate activities in your body, but they do it in different ways. The nervous system uses electrical signals to send messages very quickly through nerves. It’s responsible for fast responses, like moving your hand away from something hot or reacting to a sound. The endocrine system uses chemical signals called hormones, which are released into the bloodstream by glands (like the thyroid or adrenal glands). These hormones travel to different parts of the body and control slower processes, like growth, metabolism, and mood changes. Body Balance – Endocrine System Learning Intention Success Criteria Students understand what the I can describe the roles of the endocrine system is and its role in endocrine system the body. I can explain how the endocrine Students understand how the system functions through chemical endocrine system works through messengers (hormones) glands and hormones. I can describe an example of a Students understand how negative negative feedback system in the body feedback operates in the nervous to maintain homeostasis system. What does your body do when it What does your body do when it has feels too hot? run out of food reserves? What does your body do when it What does your body do when it has feels too cold? filled up its food reserves? What is the goal of these responses? What is the goal of these responses? Notice than in every case, the body always responds to the stimulus to achieve its goal by doing the opposite. This is called homeostasis. The ability for a system to remain stable when the surroundings change.  It is very important that our bodies keep healthy blood sugar levels, especially __________ If our bodies cannot manage its blood sugar levels properly, they may develop ______________ Blood sugar levels are maintained by two hormones that are secreted by the pancreas: 1. _______________ 2. _______________ 1. What blood sugar hormone is at high levels in Garfield at the moment? Why? 2. What blood sugar hormone is at low levels in Garfield at the moment? Why? 3. What organs do each of these hormones act on? 4. Draw a simple graph showing how these hormone and sugar levels change over time if he: Doesn’t eat. Eats a meal 2 hours later.  Heat balance (___________________) involves the nervous and endocrine systems. Set point temperature for humans is ~_____oC. This is the temperature our cells work best in. It is thermoreceptors in the brain that detect changes in blood temperature which is an indicator of body temperature.  Most of the heat needed to maintain a set point temperature is generated during _______________ of ________________ Most of the heat lost from the body is by radiation from the skin surface and evaporation of sweat.  This system of control is called ____________ _________________ The response aims to ___________ (go against) the original stimulus. It is thermoreceptors in the brain that detect changes in blood temperature which is an indicator of body temperature.  You constantly lose water by ______________ from skin and body wastes. Water is replaced by __________ liquids and eating foods. The kidneys are responsible for water ______________ in the body.  The kidneys filter ________________ from your blood as it flows through them. The wastes and water pass through a _______________ duct where much of the water is reabsorbed into the blood. Urine flows into the bladder as waste. What would diabetics have a lot of in their urine and why?  Nerves and hormones control the amount of water __________ and _________________ by the kidneys. ______________ in the brain (neurons) detect the levels of water in the blood. If water levels are low (___________), a hormone called _______________ hormone (ADH) is made in the brain and Zooming in on a kidney… secreted into the blood. ADH reaches the kidney and enables it to reabsorb more water into the blood.  Type 1 Diabetes: Occurs when insulin cannot be produced, and glucose cannot be removed from the blood. This can cause Hyperglycaemia and Hypoglycaemia. Hyperthermia: When the internal temperature drops too low and the body cannot regulate it.