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11/06/2015 Bio 2.3 Demonstrate understanding of adaptation of plants or animals to their way of life -> taxonomy -> wideshot of systems and diversity -> adaptations -> insects, mammals and fish -> review/ making connections Phylogenetics Coz life is amazing but can be hard to get your head around Kingdom: Animalia Phylum: Chordates Class: Mammals Order: Primates Family: Hominins genus: Homo Species: sapiens Phylum Cnidaria Phylum Mollusca 1 11/06/2015 Arthropoda Mission: Make a mnemonic This unit we will be focussing on 3 taxonomic groups. • Kingdom • Phylum • Class • Order • Family • Genus • Species Phylum Arthropoda – Class insecta • jointed limbs • three pairs of legs • often have wings • compound eyes • Tracheal gas exchange Phylum Chordata – Class Fish (Pisces) Phylum Chordata – Class Mammalia • Aquatic • Scales (usually) • Gills for gas exchange • Closed blood system • Young are fed milk • Hairy not furry • Large brain • 3 groups – Monotremes, Marsupials 2 11/06/2015 An adaptation is… Adaptation The adjustment of behaviour or physiology of an organism to become more suited to their environment and lifestyle. Why adapt? To survive! An environment tends to eliminate living things that are not suited to it. A plant that was not adapted to conserve moisture would soon die in the desert. Adapting to look like something you’re not “According to Charles Darwin's theory of evolution by natural selection, the organisms adapt to their environment to become better fitted to survive and passing their genes on to the next generation. “ Adapting to the cold Adapting to the heat 3 11/06/2015 People do it too Adjusting to different air supply issues In order to operate in extreme environments, some animals have evolved different types of blood composition: the sperm whale and the bar-headed goose of Asia. Both these species have an uncanny ability to store a lot more oxygen in their blood cells than other animals. …and some species get really clever…. Like a fish that can breathe air • In tropical and equatorial areas • Massive seasonal changes in water levels • Lungfish (Dipnoi) create a mucus sack to protect themselves through the drought. • Some species of catfish and eel not only breathe air, but also travel on land between pools. • Take oxygen from the air through the use of a specialized area of their intestines. Gas exchange + Respiration + Breathing Your mission 1. What is the purpose of gas exchange? • What is the purpose of gas exchange? • Name the respiratory gases • How are gasses exchanged with the environment? • Contrast air and water in terms of the challenges they present for gas exchange The purpose of gas exchange is to exchange oxygen and carbon dioxide with the atmosphere. Oxygen is required by all the cells of the body for respiration, the process in which energy is extracted from the glucose in the food an animal eats. The waste products of respiration are CO₂ and water. CO₂ leaves the body through the same process that oxygen is absorbed, only in reverse. Gas exchange absorbs O₂ from the environment and releases CO₂. 4 11/06/2015 2. Name the respiratory gasses • O₂ / Oxygen • CO₂/ Carbon dioxide 3. How are gases exchanged with the environment? Gases are exchanged with the environment through the process of diffusion. First the gasses in the environment need to reach the surfaces across which diffusion can occur, this usually happened via breathing. • Diffusion across a semi-permeable membrane and into the body Transport system to the cells Transport of waste products out of the body Features of a gas exchange surface Your mission • Read ‘Gas exchange’ page 211 Write definitions for: 1. Respiration 2. Gas exchange 3. Breathing 4. Diffusion Consider the role of each of these in gas exchange for an organism 4. Contrast air and water in terms of the challenges they present for gas exchange • O₂ content is higher in air than water • What does this mean for the animal ?(Size of GE surfaces, Energy consumption, efficiency of the process). • In the water surfaces are less likely to dry out (what mechanisms do land animals need to prevent this?) Situations where the rule is different – high altitude or stagnant water, and what this means for the animal (Lower energy use, ability to store O₂ etc…). How is the air up there? Mountain Altitude Oxygen content Sea level 0m ~20% Mt Cook 3,724 m ~13% Tibetan plateau 4,000m ~12% Kilimanjaro 5,791m Mt Everest • Do question 1 on page 217 • Read ‘mammals” and “Breathing” 214-217 8,839m ~10% ~6.8% Oxygen in the air can be affected by altitude and temperature. Higher altitude = less dense = less oxygen molecules in a breath Warmer = less dense = less oxygen molecules in a breath http://www.higherpeak.com/altitudechart.html What does it mean? • Mountain climbers need specialised breathing equipment at very high altitudes • Over time the human body can adapt to some changes: haemoglobin concentrations Heart rate • And some people are equipped to adapt better than others http://www.nature.com/ng/journal/v46/n9/abs/ng.3067.html 5 11/06/2015 Animals that live at high altitudes Animals that need more oxygen Big: Elephant Bar headed goose • Higher lung capacity • Higher heart rate • Alt 7,000m+ • Short term acclimatisation Tibetan Yak • Larger lungs and heart • More efficient transport of O₂ • More efficient metabolism • 3,000 - 5,000m • Long term adaptation • Breathes 310L air/ minute (6 in Humans) • Huge lungs! • Where are the lungs? How are they housed? How are they held up? • Circle of skin separating trunk from lungs. • Need to drink lots! Animals that need more oxygen Your mission Fast: Cheetah Use your books (pg211 onwards) and what we have discussed today to make notes on the following • Fastest land animal (120km/hr) • Takes lots of energy • Enlarges nostrils, sinuses, lungs, • Enlarged heart = increased blood flow • 60-150 breaths per minute (2x humans) • Fast muscles don’t store oxygen well = need a good supply 1. List the features required for diffusion 2. Describe the gas exchange system of a mammal. 3. Describe one case in which this system may need to be specialised (adapted). Include how the system is specialised and relate it to the environmental conditions it is specialised to. Dissection of a cow pluck: Observe Draw a diagram of a mammal gas • Thin • Moist • Large surface area exchange system. • • • • • • Trachea Bronchus, bronchiole Rings of cartilage Lung Alveoli And consider how it relates to the circulatory system • Include the features you observed • Annotate your diagram with how some of these features are adapted to a mammals way of life • Refer to 214-216 in your textbook for more info 6 11/06/2015 Thinking points Have you? • What are the features required of a gas exchange system? • Why are the lungs so bloody? • Any adaptations of a mammal system to help them with gas exchange? • Annotated diagram of a mammal respiratory system – what is an annotated diagram? 1. Listed the features required for diffusion. 2. Describe the gas exchange system of a mammal. 3. Describe one case in which this system may need to be specialised (adapted). Include how the system is specialised and relate it to the environmental conditions it is specialised to. Gas exchange in insects https://www.youtube.com/watch?v=wMbi_NcI2JY Spiracles 7 11/06/2015 Read page 212 – “gas exchange in insects” Do question 7 on page 217 Paragraph format including: • Advantages • Disadvantages/ limitations • Similarities • Differences Insects breathe air….usually -> So what are your options if you breathe air but live in the water? -> What are the advantages/ disadvantages? Silly science Friday • https://www.youtube.com/watch?v=yejDghqigW0 – Breathing underwater • https://www.youtube.com/watch?v=YtryV9qItsg - freediving • http://www.sciencealert.com/watch-the-truth-about-toilet-swirl • https://www.youtube.com/user/tomcfad - science rapping • https://www.youtube.com/watch?v=IhJQp-q1Y1s – fish slapping http://www.npr.org/sections/krulwich/2012 /02/24/147367644/six-legged-giant-findssecret-hideaway-hides-for-80years?sc=fb&cc=fp 8 11/06/2015 Gas exchange in fish Gas exchange in fish Counter current gas exchange • How do fish breathe? • Support? • Red? • Protection? • Moisture? • Flow? • Efficiency? • Counter current gas exchange • Just keep swimming – grey nurse Read “Gas exchange in fish” pg 213 and 214 • Do question 8 Paragraph format including: • Advantages • Disadvantages/ limitations • Similarities • Differences 9 11/06/2015 Circulatory systems and oxygen transport Insects Fish Mammals Open circulatory system Closed circulatory system Closed circulatory system Oxygen not transported in the circulatory system Single system • Blood travels from the heart to the gills, then to the body and back to the heart. • Blood looses pressure being pushed through the capillaries in the gills. • Not as efficient Double system • Blood travels from the heart to the lungs and back to the heart before being pumped around the body. • Blood looses pressure being pushed through the capillaries at the alveoli. • Blood regains high pressure at the heart before being pumped to the body = good at delivering O₂ to high demand body systems Haemolymph Blood Blood Gas exchange in fish: Dissection *Observe • Operculum • Gills • Gill arches • Gill filaments • Gill lamellae • Gill rakers • Path of water flow *Think: • Thin • Moist • Large surface area • Concentration gradient * Draw a diagram of a fish gas exchange system. • Include the features you observed • Annotate your diagram with how some of these features are adapted to a fish’s way of life • Refer to 213- 214 in your textbook for more info Gas exchange in Insects: Dissection *Observe • Spiracles • Trachea • Tracheoles? *Think: • Thin • Moist • Large surface area * Draw a diagram of an Insect gas exchange system. • Include the features you observed • Annotate your diagram with how some of these features are adapted to an insects way of life • Refer to 212 - 213 in your textbook for more info 10 11/06/2015 Revision – what’s your strategy? Revision Test is next week You will have 2 lessons to complete the test It requires you to answer both long and short form questions You can (and we encourage you to) illustrate your explanations with diagrams Make the connections – link structure to function. Compare and contrast structures and animal groups. • Do questions 2- 6 • Do questions 9-10 • Use revision sheet to study key points and memorise definitions. • Use cut and order activity to organise ideas and write descriptions of gas exchange systems. • Make flashcards to memorise definitions and key points. • Draw and annotate diagrams of Mammal, Fish and Insect respiratory systems. • Make a table to compare and contrast systems. Compare and contrast key points – AND relate structure to function/ need Mammals Fish Invertebrates Lungs + Circulatory system Gills + Circulatory system Tracheal tubes Diffusion of O₂ across a large moist surface √ √ O₂ has to dissolve then diffuse • Must keep surface moist X √ High O₂ in air (~20%) Low O₂ in water (~1%) High O₂ in air (~20%) Closed, double circulatory system Closed single circulatory system Open circulatory system Efficient at transporting O₂ to the cells Efficient at getting O₂ from water Mostly passive – not very efficient. 11