B5 Homeostasis & Response Flashcards
<p>What is <b>Homeostasis</b>?</p>
<p style="text-align: center;">Homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.</p>
<p>What three internal factors are controlled by Homeostasis in the human body?</p>
<ul><li>Body Temperature</li><li>Blood Glucose Concentration</li><li>Water content in blood and cells</li></ul>
<p>Why does homeostasis maintain optimum conditions?</p>
<p>Homeostasis maintains optimum conditions for:</p>
<ul><li>Enzyme Action</li><li>Cell Structure</li><li>Chemical Reactions</li> so the can function in optimum conditions</ul>
<p>What are the two types of responses that are used to control conditions in the human body?</p>
<ul><li>The Nervous System</li><li>The Endocrine System (Hormones)</li></ul>
<p>What is the order of how the human nervous system works?</p>
<p>Stimulus→Receptor→Sensory Neurone→Relay Neurone→Coordination Centre→Motor Neurone→Effector→Response</p>
<p>What is a <b>receptor cell</b>?</p>
<p>A receptor cell is a cell that detects stimuli (changes in the internal or external environment)</p>
<p>What is the purpose of a <b>coordination centre</b>?</p>
<p>Coordination centres receive and process information from receptor cells and then send out signals to coordinate the response of the body</p>
<p>Name the three coordination centres in the human body?</p>
<ul><li>Brain</li><li>Spinal Cord</li>Pancreas</ul>
<p>Name the two types of effectors?</p>
<ul><li>Muscles</li><li>Glands</li></ul>
<p>What do effectors do to bring about a response?</p>
<ul><li>Muscles will contract</li><li>Glands secrete enzymes/hormones</li></ul>
<p>What is a <b>Negative Feedback loop</b>?</p>
<p>A continuous cycle of events that responds when conditions change away from the optimum point and causes it to return conditions back to this optimum point</p>
<p>What is the role of the Human Nervous System?</p>
<p>The Human Nervous System enables humans to react to their surroundings and coordinate their behaviour</p>
<p>What are the two organs in the <b>Central Nervous System</b>?</p>
<ul><li>Brain</li><li>Spinal Cord</li></ul>
<p>What is the purpose of the <b>Peripheral Nervous System</b>?</p>
<p>The Peripheral Nervous System carries information to and from the CNS</p>
<p>What are the three types of neurons?</p>
<ul><li>Sensory (Receptor Cells→CNS)</li><li>Relay (CNS→CNS)</li><li>Motor (CNS→Effector [Muscle or Gland])</li></ul>
<p>What is a <b>synapse</b>?</p>
<p>A synapse is a gap between two neurons</p>
<p>What is the <b>Endocrine</b> system?</p>
<p>The endocrine system is the collection of glands that produce hormones that regulate internal conditions</p>
<p>Name the hormone that controls the 'flight or fight' reaction in humans</p>
<p>Adrenaline</p>
<p>Where is <b>adrenaline</b> produced?</p>
<p>Adrenal Gland</p>
<p>What are the effects of adrenaline on the body?</p>
<ul><li>Increases heart rate<ul><li>This increases the delivery of oxygen and glucose to the brains and muscle</li></ul></li></ul>
<p>Where is <b>Thyroxine</b> made?</p>
<p>Thyroid Gland</p>
<p>What does Thyroxine do to the body?</p>
<p>Thyroxine increases the basal metabolic rate which increases growth and development?</p>
<p>What is <b>Negative Feedback</b>?</p>
<p>Negative feedback is a mechanism used by the body to bring its internal environment back to normal when the level of something gets too high or too low</p>
<p>How is Thyroxine controlled?</p>
<p>Thyroxine is controlled by Negative Feedback</p>
<ul><li>The <b>hypothalamus</b> monitors the concentration of Thyroxine in the blood</li><li>If levels of Thyroxine are too low, the hypothalamus produces <b>thyroid releasing hormone (TRH)</b></li><li>TRH stimulates the <b>pituitary gland</b> to produce <b>thyroid stimulating hormone (TSH)</b></li><li>TSH stiulates the <b>thyroid gland</b> to produce thyroxine</li><li>When thyroxine levels return back to normal, TRH is no longer released - causing the production of TSH to stop</li></ul>
=<p style="text-align: center;">What internal conditions are controlled by negative feedback?</p>
<ul>Thyroxine levels<li>Temperature</li><li>Water levels</li><li>Blood sugar levels</li></ul>
<p>How are hormones transported around the body?</p>
<p>Via the bloodstream</p>
<p>What is monitored for changes in glucose concentration?</p>
<p>The blood</p>
<p>What controls the response to changes in blood glucose concentration?</p>
<p>The Pancreas</p>
<p>What hormone is produced if blood glucose concentration is too high?</p>
<p>Insulin</p>
<p>How does insulin help lower blood glucose concentration?</p>
<p>Insulin causes glucose to move from the blood to the cells and triggers the conversion of glucose into glycogen</p>
<p>What hormone is produces if glucose concentration is too low?</p>
<p>Glucagon</p>
<p>How does glucagon help increase blood glucose concentration?</p>
<p>Glucagon triggers the breakdown of glycogen into glucose, which is released into blood</p>
<p>Where is glycogen stored?</p>
<ul><li>Muscle cells</li><li>the Liver</li></ul>
<p>Compare the speed and duration of hormonal contolled compared to nervous control</p>
<p>Hormones are slower to act but act for longer as they are effective up to when the hormone is broken down</p>
<p>How is Type 1 diabetes caused?</p>
<p>Type 1 diabetes is caused by an inability to make insulin in the pancreas</p>
<p>How is Type 2 diabetes caused?</p>
<p>Type 2 diabetes is caused
| a lack of response by cells to insulin</p>
<p>What are some secondary sexual characteristics that occur during puberty for males?</p>
<ul><li>Hair growth on the face, pubic region and under arms</li><li>Voice deepens</li><li>growth spurt</li><li>Sperm production</li></ul>
<p>What are some secondary sexual characteristics that occur during puberty for females?</p>
<ul><li>Breasts develop</li><li>Hips widen</li><li>Hair growth in pubic area and under arms</li><li>Growth spurt</li><li>Menstrual cycle</li></ul>
<p>What is the main female hormone involved in development and reproduction?</p>
<p>Oestrogen</p>
<p>What is the main male hormone involved in development and reproduction?</p>
<p>Testosterone</p>
<p>Which gland produces Testosterone?</p>
<p>Testes</p>
<p>Which gland produces oestrogen?</p>
<p>Ovaries</p>
<p>What does Testosterone cause to happpen in men?</p>
<p>Stimulates sperm production</p>
<p>What does Oestrogen cause to happen in women?</p>
<p>Menstural cycle</p>
<p>How often is an egg released from the ovaries?</p>
<p>Around 28 days</p>
<p>What does <b>Follicle Stimulatin Hormone (FSH)</b> cause?</p>
<p>FSH matures the eggs in the ovaries</p>
<p>What does <b>Luteinising Hormone (LH)</b> cause?</p>
<p>LH stimulates the release of an egg from the ovaries</p>
<p>Which hormones are involved in the maintenance of the uterus lining</p>
<p>Oestrogen & Progesterone</p>
<p>How do <b>Oral Contraceptives</b> containing hormones prevent pregnancy?</p>
<p>It inhibits FSH production so no eggs mature</p>
<p>How does an injection, implantation or skin patch containing slow release progesterone prevent preganacy?</p>
<p>Progesterone inhibits the maturation of eggs</p>
<p>How do barrier methods, such as condoms or diaphragms, prevent pregnancy?</p>
<p>Barrier methods prevent sperm reaching the egg</p>
<p>How do <b>Intrauterine devices</b> prevent pregnancy?</p>
<p>Intrauterine devices prevents the implantation of an embryo AND/OR releases hormones</p>
<p>How does <b>spermicide</b> prevent pregnancy?</p>
<p>Spermicide kills/disables sperm</p>
<p>How does <b>surgical sterilisation</b> prevent pregnancy?</p>
<p>Prevents sperm or egg being released by a male of female</p>
<p>What are <b>Neurotransmitters</b>?</p>
<p>Neurotransmitters are chemicals that diffuse across synapes and bind to receptors on the next neurone</p>
<p>What is a <b>Reflex Action</b>?</p>
<p>A Reflex Action is an unconcious response that allows a person to respond to dangerous situations automatically and rapidly via a reflec arc</p>
<p>What is a <b>Reflex Arc</b>?</p>
<p>A Reflex Arc is a neural path that controls a reflex</p>
<p>What are the Components of a Reflex Arc?</p>
<p>Stimulus→Receptor→Sensory Neurone→Motor Neurone→Effector→Response</p>
<p>How do Neurones work?</p>
<ul><li>An electrical impulse reaches the end of the Neurone before the synapse</li><li>This triggers the release of chemicals called <b>electrotransmitters</b></li><li>The Neurotransmitters diffuse across the <b>synapse</b> (gap) between the neurones</li><li>The neuortransmitters bind to receptors at the end of the next neurone</li><li>The presence of the neurotransmitter causes the production of a new electrical impulse in the next neurone</li></ul>
<p>What is a <b>synapse</b>?</p>
<p>A synapse is a junction between neurones</p>
<p>Why is it hard to treat brain damage or problems in the brain?</p>
<p>We don't understand the brain well</p>
<p>What are the three main parts of the brain?</p>
<ul><li>Medulla</li><li>Cerebellum</li><li>Cerebral Cortex</li></ul>
<p>What is the <b>Medulla</b> responsible for?</p>
<p>The Medulla is the part of the brain that controls <b>unconcious activities</b>. This includes <b>breathing and heartbeat</b></p>
<p>What is the <b>Cerebellum</b> responsible for?</p>
<p>The Cerbellum is responsible for <b>muscle coodination</b>. This includes <b>Movement, posture, balance and speech</b></p>
<p>What is the <b>Cerebral Cortex</b> responsible for?</p>
<p>The Cerebral Cortex is responsible for <b>concious thought</b>. This includes <b>memory, language and intelligence</b></p>
<p>What is the function of the <b>Cornea</b>?</p>
<p>The <b>transparent frontal part</b> of the eye that <b>refracts light</b></p>
<p>What is the function of the <b>Sclera</b>?</p>
<p>The white of the eye is the opaque <b>protective outer</b> layer</p>
<p>What is the function of the <b>Optical Layer</b>?</p>
<p>The Optic Layer transmits (sends) visual information (as electrical impulses) from the retina to the brain</p>
<p>What is the function of the <b>Retina</b>?</p>
<p> The Retina is full of receptor cells, which are sensitive to both the brightness (light intensity) and the colour of light</p>
<p>What is the function of the <b>Pupil</b>?</p>
<p>The Pupil is a hole in the centre of the iris, through which light passes</p>
<p>What is the function of the <b>Iris</b>?</p>
<p>The Iris controls pupil diameter and the quantity of light reaching the retina</p>
<p>What is the function of the <b>Suspensory Ligaments</b>?</p>
<p>Suspensory Ligaments is ring of fibres that connect ciliary muscles to the lens</p>
<p>What is the function of <b>Ciliary Muscles</b>?</p>
<p>Ciliary Muscles are a ring of smooth muscle that changes the shape of the lens to focus light</p>
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