B2 Organisation Flashcards
<p>What is a <b>tissue</b>?</p>
<p>A tissue is a group of similar cells that act together to perform a function</p>
<p>What are <b>Epithelial Tissue</b>?</p>
<p>Epithelial tissue is a lining on the outer suface of organs and blood vessels</p>
<p>What is the <b>basic unit</b> of life?</p>
<p><b>Cells</b></p>
<p>What are <b>Organs?</b></p>
<p>Organs are groups of distinct tissues that work together to perform a specific function</p>
<p><b>What are Organ Systems</b>?</p>
<p>Organ systems are groups of organs that work together to perform a particular role</p>
<p>What is an <b>Organism</b>?</p>
<p>An Organism is the highest level of organisation in a multicellular organism and consists of multiple organ systems</p>
<p>What are the levels of organisation in multicellular organisms?<i>(Starting with the least complex)</i></p>
<p></p>
<ol>
<li>Cell</li><li>Tissue</li><li>Organ</li><li>Organ System</li><li>Organism</li>
</ol>
<p>What are the Organs in the <b>Digestive System</b></p>
<p></p>
<ul><li>Large Intestine</li><li>Small Intestine</li><li>Liver</li><li>Stomach</li><li>Glands</li></ul>
<p>What is an <b>enzyme</b>?</p>
<p>An enzyme is a protein that increases the rate of reaction</p>
<p>Enzymes are also known as <b>biological catalysts</b></p>
<p>What is the <b>active site</b> of an enzyme?</p>
<p>The active site of an enzyme binds a specific <b>substrate</b></p>
<p>Describe the <b>lock and key mechanism</b> of enzyme action</p>
<p>The active site is like a lock and the substrate is a key</p>
<p>In the same way, there is usually only one enzyme for every substrate</p>
<p>What does <b>denatured</b> mean?</p>
<p>When an enzyme is denatured, it means its structure is altered and can no longer catalyse a reaction</p>
<p>Which <b>factors</b> denature an enzyme?</p>
<ul><li>High Temperatures</li><li>Changing pH away from optimum pH</li></ul>
<p>What are digestive enzymes used for?</p>
<p>Digestive enymes are used to break down large food molecules for absorption</p>
<p>Where is <b>bile</b> produced?</p>
<p>Bile is produced in the Liver</p>
<p>Where is bile stored?</p>
<p>Bile is stored in the Gall Bladder</p>
<p>What are the uses of bile?</p>
<ul><li>Emulsification</li><li>Neutralisation of HCl Acid</li></ul>
<p>What is Emulsification?</p>
<p>Emulsification is a process that breaks up fats into timy droplets</p>
<p>Why is Bile used for <b>neutralisation</b>?</p>
<p>Enzymes in the small intestine best operate in Alkaline conditions</p>
<p>The bile neutralises Hydrochloric Acid from the stomach to stop these enzymes from becoming denatured</p>
<p>What is <b>Amylase</b>?</p>
<p>Amylase is a type of <b>carbohydrase</b> that breaks down starch in our bodies</p>
<p>What does amylase break down starch into?</p>
<p>Starch → Maltose (+ other simple sugars)</p>
<p>Where are the <b>action sites</b> of Amylase?</p>
<p>The action sites of amylase are:</p>
<ul><li>The Small Intestine</li><li>The Mouth</li></ul>
<p>Where is Amylase produced from?</p>
<p>Amylase is produced in:</p>
<ul><li>Pancreas</li><li>Salivary Glands</li></ul>
<p>What is the enzyme that breaks down <b>Proteins</b></p>
<p>Protease</p>
<p>What does Protease break Proteins into?</p>
<p>Protein → Amino acids</p>
<p>What are the action sites of <b>protease</b>?</p>
<p>The action sites of protease are:</p>
<ul><li>Small Intestine</li><li>Stomach</li></ul>
<p>Where is Protease produced?</p>
<p>Protease is produced in the:</p>
<ul><li>Pancreas</li><li>Stomach</li></ul>
<p>What is <b>Lipase</b>?</p>
<p>Lipase is a digestive enzyme that breaks down <b>Lipids</b></p>
<p>What does Lipase break Lipids into?</p>
<p>Lipid → glycerol + 3 fatty acids</p>
<p>Where is Lipase produced?</p>
<p>Lipase is produced in the:</p>
<ul><li>Small Intestine</li><li>Pancreas</li></ul>
<p>What are the 3 types of <b>blood vessels</b> around the body?</p>
<p>The 3 blood vessels around the body are:</p>
<ul><li>Veins</li><li>Arteries</li><li>Capillaries</li></ul>
<p>What is the order in which food passes through the digestive system?</p>
<ol><li>Mouth</li><li>Oesophagus</li><li>Stomach</li><li>Small Intestine</li><li>Large Intestine</li><li>Rectum</li><li>Anus</li></ol>
<p>What is the function of the mouth in digestion?</p>
<p>To mechanically break up food into smaller pieces to increase surface area (Mechanical Digestion)</p>
<p>What are two functions of saliva in digestion?</p>
<ol><li>To moisten food to allow easier swallowing</li><li>To start chemical digestion by containing salivary amylase</li></ol>
<p>What is the function of stomach acid?</p>
<p>To kill potentially pathogenic microorganisms in food</p>
<p>What is the function of the small intestine?</p>
<p>To absorb carbohydrates, lipids, amino acids, vitamins and mineral ions from digested food</p>
<p>What are the adaptions of the small intestine and the cell lining of the small intestine that aid the absorption of digested molecules?</p>
<ul><li>Small intestine has structures called <b>villi</b> which increase surface area</li><li><b>Epithelial cells</b> lining the villi have <b>microvilli</b> on their surface which further increase surface area</li></ul>
<p>What is the function of the large intestine?</p>
<p>To absorb water from digested food</p>
<p>What is the function of the liver in digestion?</p>
<p>To produce bile, an emulsifier of lipids and neutraliser of Hydrochloric Acid</p>
<p>What is the function of the gall bladder?</p>
<p>To store bile until it can be released into the small intestine</p>
<p>What is the function of the rectum?</p>
<p>To store undigested material before excretion</p>
<p>What is a <b>substrate</b>?</p>
<p>A molecule or atom which is acted upon by an enzyme</p>
<p>How does an enzyme “recognise” its specific substrate?</p>
<p>A complementarily-shaped <b>active site</b> – a region on the enzyme which fits the substrate.</p>
<p>Name two environmental conditions that can change an enzyme’s active site</p>
<ol><li>pH (either higher or lower than optimum)</li><li>Higher than optimal temperature</li></ol>
<p>Where is <b>carbohydrase</b> produced?</p>
<ul><li>Salivary glands</li><li>Pancreas</li><li>Small Intestine</li></ul>
<p>What do carbohydrases break down and what is produced?</p>
<p>Carbohydrates to simple sugars (e.g. amylase breaks down starch to glucose)</p>
<p>Where is <b>protease</b> produced in the body?</p>
<ol><li>Stomach</li><li>Pancreas</li><li>Small Intestine</li></ol>
<p>What do proteases break down and what is produced?</p>
<p>Proteins to amino acids</p>
<p>Name where lipase is made in the body</p>
<ol><li>Stomach</li><li>Pancreas</li><li>Small Intestine</li></ol>
<p>What do lipases break down and what is produced?</p>
<p>Lipids (fats) to 3 fatty acids and 1 glycerol</p>
<p>What are the products of digestion used for?</p>
<p>To build new carbohydrates, lipids and proteins</p>
<p>How does bile help the action of lipase? </p>
<ol><li>Provides alkaline conditions by neutralising acid from the stomach</li><li>Emulsifies fat to form small droplets with a larger surface area</li></ol>
<p>What is the Benedict's test and how do you carry it out?</p>
<p>The Benedict's test is for testing if there is sugar in food samples</p>
<ul><li>Add Benedict's reagent</li><li>leave in a hot water bath (above 60°C) for 5 minutes</li><li>if it turns orange/brick red, it contains sugar</li></ul>
<p>What is the Biuret test and how do you carry it out?</p>
<p>For testing if there is protein in food samples. Add Biuret reagent (blue liquid). If it turns lilac, protein is present</p>
<p>Which food test can be carried out with iodine?</p>
<p>Testing for the presence of starch. Add iodine (reddish brown) drops to food sample. If it turns blue/black, it contains starch</p>
<p>Which system transports substances around the body?</p>
<p>The circulatory system</p>
<p> What is the heart?</p>
<p>An Organ that pumps blood around the body</p>
<p>What is the function of the heart?</p>
<p>Pump blood around the body</p>
<p>What are the walls of the heart made from?</p>
<p>Muscle Tissue</p>
<p>Name the two types of chambers in the heart</p>
<p>Atria and Ventricles</p>
<p>Which are the upper chambers of the heart?</p>
<p>Atria</p>
<p>Which are the lower chambers of the heart?</p>
<p>Ventricles</p>
<p>Where do the atria force blood upon contraction?</p>
<p>Into the Ventricles</p>
<p>Where do the ventricles force blood upon contraction?</p>
<p>Out of the Heart</p>
<p>What is the job of the heart valves?</p>
<p>To prevent backflow of blood in the heart</p>
<p>To where does blood flow after leaving the right hand side of the heart?</p>
<p>To the Lungs</p>
<p> To where does blood flow after leaving the left hand side of the heart?</p>
<p>The rest of the body</p>
<p>Through which blood vessel does blood flow away from the heart?</p>
<p>Arteries</p>
<p>Through which blood vessel does blood flow back into the heart?</p>
<p>Veins</p>
<p>Name the blood vessel by which blood leaves to the rest of the body</p>
<p>Aorta</p>
<p>Name the blood vessel by which blood arrives back from the rest of the body</p>
<p>Vena Cava</p>
<p>Name the blood vessel by which blood leaves the heart to the lungs</p>
<p>Pulmonary Artery</p>
<p>Name the blood vessel by which blood leaves the lungs to go back to the heart</p>
<p>Pulmonary Vein</p>
<p> Which type of blood vessels have thick walls containing muscle tissue and elastic fibres?</p>
<p>Arteries</p>
<p>Which blood vessels have thinner walls and contain valves?</p>
<p>Veins</p>
<p>Name two key adaptations of capillaries</p>
<ol><li>Very thin (only one cell thick) to reduce distance diffusion has to occur across</li><li>Very narrow to reduce distance diffusion has to occur across</li></ol>
<p>Where is the “natural” pacemaker of the heart located?</p>
<p>Right Atrium</p>
<p>Where are the lungs located?</p>
<p>Upper Part of the Body - Thorax</p>
<p>What protects the lungs?</p>
<p>The Ribcage</p>
<p>What separates the lungs from the abdomen (lower part of body)?</p>
<p>The Diahpragm</p>
<p>Which gas diffuses into the bloodstream?</p>
<p>Oxygen</p>
<p>Which gas diffuses out of the bloodstream?</p>
<p>Carbon Dioxide</p>
<p>Name the two structures which branch off from the trachea</p>
<p>Bronchi</p>
<p>Name the structure which branch off from the bronchi</p>
<p>Bronchiole</p>
<p> What are the small gas exchange structures in the lungs called?</p>
<p>Alveoli</p>
<p>Describe four adaptations alveoli have to make them well suited for gas exchange</p>
<ol><li>Thin walls (one cell thick)</li><li>Extensive capillary network covering the surface of each alveolus</li><li>Efficient movement of blood through capillaries to maintain a concentration gradient for diffusion of oxygen & carbon dioxide</li><li>Folded inner surface to give a large surface area</li></ol>
<p>What is the liquid part of blood called?</p>
<p>Plasma</p>
<p>What are the three main cell types found in blood? </p>
<ol><li>Red Blood Cells</li><li>White Blood Cells</li><li>Platelets</li></ol>
<p>What does blood plasma transport from the organs to the lungs?</p>
<p>Carbon Dioxide</p>
<p>What does blood plasma transport from the small intestine to other organs?</p>
<p>Soluble products of digestion</p>
<p>What does blood plasma transport from the liver to the kidneys?</p>
<p>Urea</p>
<p>What do red blood cells transport?</p>
<p>Oxygen</p>
<p>How do Red Blood Cells transport Oxygen?</p>
<p>When there is a high concentration of oxygen, oxygen binds with haemoglobin in Red Blood Cells and forms Oxyhaemoglobin</p>
<p>When there is a low conentration of oxygen, the oxygen is released from the haemoglobin</p>
<p>How are Red Blood Cells adapted to make the transfer of oxygen more efficient?</p>
<ul><li>They contain haemoglobin - a red protein that combines with oxygen</li><li>They have no nucleus so they can contain more haemoglobin</li><li>They are small and flexible so that they can fit through narrow blood vessels</li><li>They have a biconcave shape (flattened disc shape) to maximise their surface area for oxygen absorption</li></ul>
<p> In the lungs, which reversible reaction occurs?</p>
<p>Haemoglobin + oxygen ⇆ oxyhaemoglobin</p>
<p>What do white blood cells do?</p>
<p>Defend the body against microorganisms</p>
<p> What do platelets do?</p>
<p>Help clot the blood at wound sites</p>
<p>What are the coronary arteries?</p>
<p>Blood vessels that supply the heart muscle tissue</p>
<p>What occurs in Coronary Heart Disease (CHD)?</p>
<p>The coronary arteries become blocked with fatty deposits, narrowing them</p>
<p>Why is Coronary Heart Disease a problem?</p>
<p>Reduces the flow of blood to the heart, therefore reducing the supply of oxygen, glucose and pickup of carbon dioxide</p>
<p>How do stents treat Coronary Heart Disease (CHD)?</p>
<p>Re-opens the blocked coronary artery, restoring blood flow</p>
<p>How do statins treat Coronary Heart Disease (CHD)?</p>
<p>Decreases the blood concentration of cholesterol, which reduces build-up of fatty deposits in the coronary arteries</p>
<p>Why are faulty heart valves life-threatening?</p>
<p>Allows backflow of blood</p>
<p>Name two sources of replacement heart valves</p>
<ol><li>Mechanical</li><li>Biological - Pigs/Sheep</li></ol>
<p>Describe a treatment used in the case of total heart failure</p>
<p>Heart Transplant</p>
<p>Name a risk of surgical intervention in heart disease</p>
<p>Infection</p>
<p>When would an artificial heart be used?</p>
<ol><li>To allow the heart to rest and recover</li><li>To keep the patient alive whilst they wait for a transplant</li></ol>
<p>What is <b>health</b>?</p>
<p>The state of physical and mental well-being</p>
<p>What are the two types of disease?</p>
<p>Communicable (caused by a pathogen) and non-communicable</p>
<p>Give an example of how different diseases can interact</p>
<ul><li>Defects in the immune system mean that an individual is more likely to suffer from infectious diseases</li><li>Viruses living in cells can be the trigger for cancers</li><li>Immune reactions initially caused by a pathogen can trigger allergies such as skin rashes and asthma</li><li>Severe physical ill health can lead to depression and other mental illness</li></ul>
<p>Name three factors, other than pathogens, which can influence health</p>
<ol><li>Diet</li><li>Stress</li><li>Life situations</li></ol>
<p>What is a risk factor?</p>
<p>A factor linked to an increased rate of disease</p>
<p>Give two general examples of a risk factor</p>
<ol><li>The lifestyle of a person</li><li>Substances in the person’s body or environment</li></ol>
<p>What is meant by "correlation does not imply causation"?</p>
<p>Just because two variables are correlated (one increases as the other increases), doesn't mean that one causes the other e.g. ice cream sales and number of sunburnt people</p>
<p>Some risk factors have had a causal mechanism proven for some diseases. Name three examples</p>
<ul><li>The effects of diet, smoking and exercise on cardiovascular disease</li><li>Obesity as a risk factor for Type 2 diabetes</li><li>The effect of alcohol on the liver and brain function</li><li>Carcinogens, including ionising radiation, as risk factors in cancer</li><li>The effects of smoking and alcohol on unborn babies</li><li>The effect of smoking on lung disease and lung cancer</li></ul>
<p>Most diseases are termed “multi-factorial”. What does this mean?</p>
<p>Multiple risk factors contributing to the person developing the disease</p>
<p>What is <b>cancer</b>?</p>
<p>Cancer is a group of diseases, where changes in cells lead to uncontrolled growth and division of cells</p>
<p>How do cancers develop?</p>
<p>DNA in cells is changed (mutated)</p>
<p>What is a <b>benign tumour</b>?</p>
<p>A growth of abnormal cells which is contained in <b>one area within the body</b> and will <b>not invade other body parts</b></p>
<p>What is a <b>malignant tumour</b>?</p>
<p>A growth of abnormal cells which invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours</p>
<p>Name some main lifestyle risk factors for cancer</p>
<p>Two from:</p>
<ul><li>Smoking</li><li>Excessive alcohol use</li><li>Obesity</li><li>UV Exposure</li><li>Genetics</li></ul>
<p>Name six plant tissues</p>
<ul><li>Epidermal</li><li>Palisade Mesophyll</li><li>Spongy Mesophyll</li><li>Xylem</li><li>Phloem</li><li>Meristem</li></ul>
<p>Name three plant tissues</p>
<p>Any three from:</p>
<ul><li>The epidermis</li><li>The Palisade Mesophyll</li><li>The Spongy Mesophyll</li><li>The Xylem</li><li>The Phloem</li><li>Guard Cells</li></ul>
<p>What is transpiration?</p>
<p>The movement of water (and minerals) from the roots to the leaves. Water eventually leaves the leaves via evaporation</p>
<p>Name four factors which affect the rate of transpiration in plants</p>
<ol><li>Temperature</li><li>Humidity</li><li>Air movement</li><li>Light intensity</li></ol>
<p>How does temperature affect rate of transpiration?</p>
<p>Higher temperature increases transpiration rate as water evaporates quicker</p>
<p>How does humidity affect rate of transpiration?</p>
<p>Higher humidity decreases transpiration rate. It increases the amount of water in the air so makes it difficult for water to evaporate</p>
<p>How does wind or air flow affect rate of transpiration?</p>
<p>More wind increases transpiration rate (it maintains a steep concentration gradient) as it carries water away from the leaves</p>
<p>How does light intensity affect rate of transpiration?</p>
<p>More light increases transpiration rate as it increases evaporation rates</p>
<p>Name the equipment used to estimate transpiration rate</p>
<p>Potometer: a device that measures the volume of water uptake in a plant shoot</p>
<p> Name three plant organs</p>
<ul><li>Roots</li><li>Stem</li><li>Leaves</li></ul>
<p>What is <b>translocation</b>?</p>
<p>The movement of sugars from the leaves to the rest of the plant</p>
<p>Describe the adaptations of xylem tissue</p>
<ul><li>Hollow tubes strengthened by lignin (Lignin strengthens and waterproofs the wall)</li><li>Dead cells to maximise space for water</li><li>No end cells, so can have a long tube</li></ul>
<p>Describe the adaptations of phloem tissue</p>
<p>Elongated cells with pores in the end cell walls to aid the movement of dissolved sugars</p>
<p>What is the role of stomata and guard cells?</p>
<p>To allow gas exchange and control water loss</p>
<p>What food test do you do to test for the presecence of Sugar?</p>
<p>Bennedict's Solution test</p>
<p>What is the method for Bennedict's solution test for sugar?</p>
<p>Add Benedict's reagent to the substance and heat for 2 minutes</p>
<p>If sugar is present, the colour will turn green, yellow or red if sugar is present</p>
<p>What is the food test to test for the presence of Lipids?</p>
<p>Ethanol Test</p>
<p>How do you know lipids are present in the ethanol test?</p>
<p>The solution turns cloudy when lipids are present</p>
<p>What is the food test to test for the presence of Protein?</p>
<p>Biuret test</p>
<p>How do you know protein is present in the Biuret test?</p>
<p>The solution turns mauve / lilac if protein is present</p>
<p>What is the food test to test for the presence of starch?</p>
<p>Iodine Test</p>
<p>How do you know starch is present in the Iodine test?</p>
<p>The solution turns blue-black</p>
<p>Why do veins have thinner walls than arteries?</p>
<p>Veins transport blood with lower pressure so don't need thick walls to withstand high pressure</p>
<p>Why do veins have a larger lumen than arteries?</p>
<p>The low pressure in veins slows blood flow. Veins have a larger cross-section (lumen) to counteract this</p>
<p>Why do veins have valves?</p>
<p>Veins have valves to prevent the backflow of blood</p>
<p>How is a malignant tumor spread?</p>
<p>A malignant tumor is spered through the bloodstream and lymph system</p>
<p>Why are benign tumors unable to spread to other parts of the body?</p>
<p>Benign tumors can't spread to other parts of the body as they surrounded by a membrane which localises them to a single region of the body</p>
<p>What is the problem with leaky valves?</p>
<p>Leaky valves allow the backflow of blood. This creates a strain on the heart</p>
<p>What is the problem with valves that don't fully open?</p>
<p>Valves that don't open fully obstruct blood flow. This means a greater force is required for blood to flow. Therefore, it causes a strain on the heart</p>
<p>What are the benefits of Artificial Hearts?</p>
<ul><li>Artificial hearts are unlikely to be rejected by the patient’s immune system, so immunosuppressant drugs (prevent rejection) are unnecessary</li><li>Artificial hearts can also be used to provide the heart with some rest to allow it to recover</li></ul>
<p>What are the drawbacks to Artificial Hearts?</p>
<ul><li>Artificial hearts can result in long and expensive stays in hospital</li><li>They can also cause blood clotting, which can potentially lead to strokes</li></ul>
<p>What are the potential disadvantages of using transplanted organs to treat heart disease?</p>
<ul><li>The transplanted organ may be rejected</li><li>Need to take immunosuppressant drugs which makes them more susceptible to contracting another disease</li></ul>
<p>What is Meristem tissue?</p>
<p>Meristem tissue is the undifferentiated cells of a plant capable of specialising into different plant cells</p>
<p>What is the function of the Palisade Mesophyll in Plants?</p>
<p>The Palisade Mesophyll or Palisade layer is where photosynthesis takes place</p>
<p>How are Palisade cells adapted to perform there function?</p>
<p>Palisade cells are packed together and and have lots of chloroplasts to maximise energy transfer in photosynthesis</p>
<p>How is the spongy mesophyll layer adapted to perform its function?</p>
<p>There are lots of air spaces which increases surface area which, in turn, increases gas exchange throughout the leaf</p>
<p>What is the function of the upper epidermis?</p>
<p>The upper epidermis or epidermal layer covers and protects the outer surface of leaves</p>
<p>How is water taken in by a plant?</p>
<ul><li>Root hair cells absorb water from the soil via osmosis (movement of water from a dilute solution to a concentrated solution)</li><li>After being absorbed by the root hair cells, the water are transported in xylem vessels up the stem and into the leaves</li><li>Once it reaches the leaves, the majority of water evaporates and the water vapour diffuses out (is lost) through open stomata</li><li>This loss of water from the leaves is known as transpiration and helps to pull water up from the roots</li></ul>
<p>How are mineral ions taken in by a plant?</p>
<ul><li>From the root, mineral ions are taken up by active transport (movement of ions and molecules across a cell membrane to an area of higher concentration)</li><li>After being absorbed by the root hair cells, the minerals are transported in xylem vessels up the stem and into the leaves</li></ul>
<p>What is the the method to measure the rate of transpiration?</p>
<p>A Potometer is used to measure the rate of transpiration</p>
<ul><li>As water is lost through the plant’s leaves, the air bubble moves</li><li>The speed of the bubble's movement shows the rate of water uptake</li><li>This is only an estimation (guess) as a small amount of the water taken up by the shoot is used in the leaves</li></ul>
<p>How is translocation different to transpiration?</p>
<p>Translocation is bidirectional (movement is both up and down the plant) whereas, transpiration can only move up</p>
<p>How are root hair cells adapted for its function?</p>
<ul><li>Lots of mitochondria for active transport of minerals</li><li>Long projections to increase surface area </li></ul>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>
<p></p>