Module 1 PDF

1.8 Atoms and elements Topic 1A: Chemistry 1. Differentiate between elements and molecules 2. Identify the roles of biologically important elements (including H, K, Na, C, Ca, Fe) 3. Differentiate between anions and cations 4. List the four major classes of macromolecules and provide examples...

1.8 Atoms and elements Topic 1A: Chemistry 1. Differentiate between elements and molecules 2. Identify the roles of biologically important elements (including H, K, Na, C, Ca, Fe) 3. Differentiate between anions and cations 4. List the four major classes of macromolecules and provide examples 5. Discuss the importance of pH and the role of buffers in body fluids Read Biology is the study of organisms. All living organisms are made of chemicals. To understand the changes that take place in living organisms you need to know the underlying chemistry. (When reviewing this section it may be helpful to refer to a copy of the periodic table in a textbook or online) All substances are made of tiny particles called atoms. An element is a substance that is made of only one type of atom. The atoms of any element are different to the atoms of any other element. So nitrogen is made from a different type of atom to sodium, and carbon atoms are different to oxygen atoms. There are about 100 different elements. These are shown in the periodic table, which is a chart with all the elements arranged in a particular way. Each element has its own name and chemical symbol. Elements have their own characteristic physical and chemical properties. The horizontal rows in the periodic table are called periods and the vertical columns are called groups. The elements in a group have similar properties to each other, for example Group 0 (the column on the far right of the periodic table) are known as the noble gases, these elements include Helium (He), Neon (Ne) and Argon (Ar), they are all unreactive gases. The periodic table is divided into non-metals and metals. You can see that most of the elements are metals.  Source: https://commons.wikimedia.org/wiki/File:Figure_B00_02_01.jpg (https://commons.wikimedia.org/wiki/File:Figure_B00_02_01.jpg ). Chemical symbols The atoms of each element are represented by a chemical symbol. This usually consists of one or two different letters, but sometimes three letters are used for newly discovered elements. For example, N represents a Nitrogen atom, and Na represents a sodium atom. The first letter in a chemical symbol is always an UPPERCASE letter, and the other letters are always lowercase. So, the symbol for a sodium atom is Na and not na, NA or nA. Atomic Structure As shown in the diagram below, an atom has a small central nucleus made up of smaller sub- atomic particles called protons and neutrons. The nucleus is surrounded by even smaller sub- atomic particles called electrons. Protons and electrons have an electrical charge. Both have the same size of electrical charge, but the proton is positive and the electron negative. Neutrons are neutral. The number of electrons in an atom is equal to the number of protons in its nucleus. This  means atoms are neutral with overall electrical charge. Source: https://images.app.goo.gl/azto1xnh4Nrg2Egq7 (https://images.app.goo.gl/azto1xnh4Nrg2Egq7). Each box in the periodic table provides the chemical symbol for an element, its atomic number and its mass number. You can use this information to calculate the number of each subatomic particle in an atom (i.e. you can work out how many protons, neutrons and electrons are in each atom of the element). Looking at the diagram below showing one box from a periodic table you can see that the symbol for a germanium atom is Ge.The atomic number tells you that the germanium atom has 32 protons in the nucleus. It will also have 32 electrons, because the number of protons and electrons in an atom is the same. The atomic mass number tells you that the total number of protons and neutrons in the germanium atom is 74. You can work out the number of neutrons from the mass number and atomic number. In this example, it is 74 – 32 = 42 neutrons.  Electronic structure The electrons in an atom are arranged in energy levels, these are also called shells or orbits. Each electron in an atom is found in a particular shell. The innermost shell (lowest energy level) fills with electrons first. Each shell can only hold a certain number of electrons before it becomes full. The first shell can hold a maximum of two electrons, the other shells are able to hold up to a maximum of 8 electrons (only true for the first 20 elements). The outermost shell is also known as the valence shell and electrons that occupy the outermost shell are also known as valence electrons. Valence electrons are the electrons of an atom that can participate in the formation of chemical bonds with other atoms (see Chemical Reactions for more information). Writing an electronic structure The electronic structure of an atom is written using numbers to represent the electrons in each energy level. For example, for sodium the electronic structure is 2,8,1 – showing that there are: 2 electrons in the first energy level, 8 electrons in the second energy level, 1 electron in the third energy level. You can work out the electronic structure of an atom from its atomic number or its position in the periodic table. The number of occupied shells is the same as the period number (row in the table) and the number of electrons in the outermost shell (valence shell) is the same as the group number (column in the table). Drawing an element's electronic structure The electronic structure of an atom can be represented in a simple diagram with circles drawn around a central nucleus representing the shells and crosses or dots added to each circle to represent the electrons occupying each shell. Select an element in the periodic table, work out which period (row) it is in, and draw that number of circles around the nucleus then work out which group the element is in and draw that number of electrons in the outer circle – with eight for Group 0 elements (except helium). Fill the other circles with as many electrons as needed, two in the first circle, and eight in the second and third circles. Finally, check that the number of electrons is the same as the atomic number. Summary What you need to know about atoms and elements: Atoms are the building blocks of all matter. They consist of three sub-atomic particles: protons, neutrons and electrons. Protons and neutrons are found in the nucleus of an atom. Protons have a positive charge, neutrons have no charge. Electrons are found in energy levels called shells or orbits around the nucleus. Electrons have  a negative charge. The charge on the proton and electron are the same size; because they have opposite charges they attract each other. Chemical reactions involve the rearrangement of electrons in the outermost shell. An element is a substance made up of atoms with the same number of protons. Elements are the simplest substances known. They can be metals or non-metals. The periodic table shows elements arranged by their atomic number. The atomic number of an atom tells us how many protons it has in the nucleus. Each element has its own name and chemical symbol, characteristic physical and chemical properties. Elements with similar properties are found in the same column of the periodic table.   1.9 Molecules, compounds and ions Read A molecule is the general term used to describe two or more atoms joined together by chemical bonds. The molecule may be an element (a pure substance made up of only one type of atom) e.g. oxygen gas (O2) or a compound. Compounds are formed when atoms from two or more different elements react together and are bonded together e.g. water (H2O) or carbon dioxide (CO2). Compounds usually have different properties from the elements they contain. Some atoms are unlikely to react with other atoms, they exist as single atoms. These are the Noble Gases, which include helium, neon and argon, their atoms have a very stable electron structure because their outer shell (valence shell) is full. All other atoms react and bond together to become more stable, i.e. they try to create a full outer shell by gaining, losing or sharing electrons. The bonds that form between atoms usually involve only the electrons in the outer shell, the valence electrons. There are two main types of chemical bond that hold atoms together: covalent and ionic bonds. Read and watch Ionic bonds To fully understand how ionic bonds form you need to know about ions and ion formation, if you are not familiar with this topic or would like to refresh your knowledge watch the FuseSchool video below (3:36min) Ionic Compounds & Their Properties | Properties of M… M…  Atoms can gain or lose electrons from their outer shell (valence shell) in chemical reactions. When they do this they form charged particles called ions. When atoms lose electrons they form positively charged ions known as cations. When atoms gain electrons to form negatively charged ions known as anions. Remember that electrons carry a negative charge and protons (in the nucleus) carry a positive charge. The diagram below shows that when an atom loses (or donates) an electron it becomes a positively charged and when an atom gains (or accepts) an eletron it becomes a negatively charged. When sodium loses one electron it is losing one negative charge. The sodium atom then has 10 negatively charged electrons and 11 positively charged protons so overall it has a net charge of 1+, this is written as Na+. When a chlorine atom gains an electron it is gaining one negative charge. The chlorine atom then has 18 negatively charged electrons and 17 positively charged protons so overall it has a net charge of 1-, this is written as Cl-. An ionic bond is formed by one atom transferring electrons to another atom to form charged particles called ions. Oppositely charged ions attract each other, this force of attraction creates the ionic bond. For example positively charged sodium ions are attracted to negatively charged chloride ions, these ions bond together and form sodium chloride.  Covalent bonds A covalent bond forms when two atoms share a pair of valence electrons. Hydrogen gas (H2) forms the simplest covalent bond - a molecule is formed by two individual hydrogen atoms joining together by sharing their single valence electron. Ionic and covalent bonding are explained in the following video (2:15min) Chemical Bonding - Ionic vs. Covalent Bonds Read Chemical equations A chemical equation represents the total chemical change that occurs in a chemical reaction using words or symbols for the substances involved. Reactants are the substances that are changed and products are the substances that are produced in a chemical reaction. For example, sodium and chlorine react together to form a compound called sodium chloride, in this example the reactants are sodium and chlorine and the product is sodium chloride, the word equation for this reaction would be written as shown below, Individual substances are separated by a plus sign, an arrow between the reactants and the products represents the reaction. Sodium + Chlorine → Sodium Chloride The chemical formula of a compound tells you how many atoms of each element the molecule contains. The table below shows the formula of some common compounds, with the number of atoms of each element in the molecule (You do not need to memorise these formulae but it is important to be able to read and understand them)   compound compound sodium hydrogen carbon sulphur oxygen name formula atoms atoms atoms atoms atoms carbon CO 1 1 monoxide carbon CO2 1 2 dioxide water H2 O 2 1 sulphur SO2 1 2 dioxide sulphuric H2SO4 2 1 4 acid sodium NaCO3 1 1 3 carbonate The small 2 after an element symbol tells you there are two atoms of that particular element in each molecule. For example, the water molecule H2O has two hydrogen atoms. Notice that you do not write a number 1 if there is only one atom of an element in a molecule. This diagram below shows that one carbon atom and two oxygen atoms combine to make up the units of carbon dioxide. Its chemical formula is written as CO2. Sometimes you see more complex formulae such as Na2SO4 and C6H12O6: a unit of Na2SO4 (sodium sulphate) contains two sodium atoms, one sulphur atom and four  oxygen atoms joined together  a unit of C6H12O6 (glucose) contains six carbon atoms, twelve hydrogen atoms and six oxygen atoms Organic and Inorganic Compounds The compounds that make up living organisms fall into two types - organic compounds and inorganic compounds. Organic compounds The term organic compound comes from the fact that most of the original organic compounds studied by scientists came from living things, however now we are able to make some organic compounds in the laboratory. Organic compounds can be recognised from their formulae - they all contain the elements carbon and hydrogen. Examples of organic compounds are carbohydrates, lipids and proteins and nucleic acids. These may be classified as (a) small biological molecules and (b) large biological molecules and polymers. Proteins are organic compounds that contain the elements nitrogen and oxygen as well as carbon, hydrogen. Proteins are often considered to be the central compound necessary for life. There are many types of proteins, but they are all made from smaller units called amino acids. Proteins vary in length, complexity and shape is based on the number and type of amino acids they are built from. The specific shape of a protein determines its function, if the shape of a protein is altered it will not perform its function as expected (see Enzymes review). The diagram below shows the structure of one type of amino acid: Inorganic compounds These are compounds that are not made by living things. They usually do not contain the element carbon but there are a few exceptions (e.g. carbon dioxide and carbon monoxide). Other examples of inorganic compounds are water (which exists as molecules) and salts (which contain ions such as potassium, calcium and chloride).  Summary What you need to know about molecules, compounds and ions: Elements form compounds in chemical reactions. Atoms of elements combine in certain fixed ratios. The ratios are determined by the combining power of atoms. Each compound has its own: name, formula, characteristic physical properties and chemical properties. Atoms are held together in compounds by chemical bonds. In the formation of an ionic bond electrons are transferred between atoms, leaving some with fewer electrons and others with more electrons, these are ions. Positively charged ions are called cations and negatively charged ions are called anions. Cations and anions are attracted to one other because of their opposite charges, this force is called an ionic bond. In the formation of a covalent bond electrons are shared between atoms. They are always shared in pairs, so a covalent bond may consist of two, four or six electrons being shared. The compounds that make up living organisms fall into two types: organic and inorganic compounds. Organic compounds can be recognised from their formulae - they all contain the elements carbon (C) and hydrogen (H).   1.10 pH Watch Watch this YouTube animation for a simple introduction to pH (6:01min) Acids And Bases Salts And pH Level - What Are Acids … Read The pH Scale This is a scale from 0 – 14. The pH scale measures hydrogen ion (H+) concentration of a substance and therefore how acidic or basic/alkaline a substance is. It ranges from 0 (strongest acid) to 14 strongest base), a pH of 7 is neutral. An indicator is a chemical that changes colour when in contact with an acid or a base. Acids Acids have a pH lower than 7 (1 to 6), the lower the number the stronger the acid. Acidic solutions turn blue litmus paper red and turn universal indicator paper red if they are strongly acidic, and orange or yellow if they are weakly acidic. Acids are corrosive when they are strong, examples of strong acids include battery acid and hydrochloric acid which is found in the stomach. Weak acids are an irritant, examples of weak acids include tomato juice and black coffee. When acids dissolve in water they produce aqueous hydrogen ions (H+) Bases / Alkalis  Substances that can react with acids and neutralise them are called bases. Bases that dissolve in water are called alkalis. Alkaline solutions have a pH greater than 7 (8 to 14). The higher the number the stronger the alkali. Alkaline solutions turn red litmus paper blue and turn universal indicator paper dark blue or purple if they are strongly alkaline (e.g. bleach), and blue-green if they are weakly alkaline (e.g. Sea water). When alkalis dissolve in water they produce aqueous hydroxide ions (OH–) Neutral solutions Neutral solutions have a pH of 7. They do not change the colour of litmus paper, but they turn universal indicator paper green. Distilled water is an example of a neutral substance. When the H+ ions from an acid react with the OH– ions from an alkali, a neutralisation reaction occurs to form water. Acid-Base balance in the human body Cellular processes are generally restricted to the middle of the pH scale between pH6 and 8. A change in pH can cause proteins in the body to denature and alter the function of enzyme activity, it can alter hormone action and disrupt cell and tissue function. Therefore it is important to maintain acid-base balance in the body. The body has a buffer system to help neutralize the blood if excess hydrogen or hydroxide ions are produced. Buffers help to keep the pH in the normal range by combining with the excess hydrogen or hydroxide ions. The most common buffers in the body are bicarbonate (HCO3-) and carbonic acid (H2CO3). Bicarbonate is produced by the kidneys and released into the bloodstream. It can combine with excess hydrogen ions to keep the pH of the blood in the normal range. When bicarbonate combines with excess hydrogen ions, it forms carbonic acid, which keeps the pH of the blood from going too low. However, if the pH of the blood gets too high, carbonic acid breaks apart to release some hydrogen ions, which brings the pH back into balance. Summary What you need to know about pH: The pH scale measures hydrogen ion (H+) concentration of a substance and therefore how acidic or basic/alkaline a substance is. Acids have a pH lower than 7, the lower the number the stronger the acid. When acids dissolve in water they produce hydrogen ions (H+). When bases are dissolved in water they are known as alkalis, they produce hydroxide ions (OH–). Alkalis have a pH greater than 7, the higher the number the stronger the alkali.  Substances with a pH of exactly 7 are neutral. Cellular processes are generally restricted to the middle of the pH scale between pH6 and 8.   1.11 Pre-workshop activity: Workshop 1 Q7 Elements There are 92 elements that exist in nature, from hydrogen to uranium. Each element has a chemical symbol, usually 1 or 2 letters of the elements name in English Latin or another language. Examples of chemical symbols are ‘H’ for hydrogen, ‘Ca’ for calcium and ‘Na’ for sodium. The periodic table is a listing of all the elements we know of to date. Four elements constitute about 96% of the body’s mass; hence oxygen, carbon, hydrogen, and nitrogen are termed the major elements. A further eight elements (the lesser elements; calcium, phosphorus, potassium, sulphur, sodium, chlorine, magnesium, and iron) contribute about 3.6% of your body mass. The remainder of your body’s mass is made up of 14 trace elements. Although very small amounts of trace elements are present in your body, they often have very important functions in the body. For example, iodine is needed to make thyroid hormones, that control metabolism, energy utilisation and growth. Practise   A component of water and most organic molecues. The ionised form makes body fluids more acidic. A part of water and other organic molecules. The gaseous form is necessary for cellular respiration Component of ATP and nucleic acids. Found in bones and teeth. Found in bones and teeth. The ionised form is needed for nerve impulses, muscle contraction, and blood clotting. Found in proteins and nucleic acids Important for maintaining water balance. Needed to generate nerve impulses. The ionised form is the main extracellular cation. Important for maintaining water balance. The ionised form is the main extracellular anion. Principle element in all organic compounds (carbohydrates, lipids, proteins, nucleic acids) Needed to generate nerve impulses. The ionised form is the main intracellular cation. The ionised forms are part of haemoglobin C Ca Cl Fe H K N Na O P  Submit   1.12 Cells and organelles Topic 1B: Cells, Tissues and Membranes 1. Define a cell 2. List the functions of the cell/plasma membrane and the structural features that enable it to perform that function 2.1. Explain how the cell membrane acts as a selectively permeable barrier 3. Describe the role and location of receptors in the cell 4. Describe the location and function of key organelles of a typical cell (mitochondria, nucleus and ribosomes) Read Combinations of many chemicals form our cells. Cells are the basic structural and functional units of the body. Each cell has a specific task and works with many other cells to help our body maintain homeostasis. A cell can be divided into three main parts: plasma (cell) membrane, cytoplasm, and nucleus. Organelles within the cytoplasm have specific functions related to cell structure, growth, maintenance, and metabolism. What is a cell? What is an organelle? Why are they important? Watch Watch Overview of cell structure (https://canvas.acu.edu.au/courses/17771/files/1375110/download?wrap=1) (located in the Week 1 Extra resources) for a great overview of cell structure and how the organelles work together to maintain cell function. Practise Click the plus symbols below for further descriptions of key organelles. (TLO T1B4)    1.16 Membrane transport Topic 1C: Diffusion and Osmosis 1. Define the processes of diffusion and osmosis and, using examples, explain their role in physiological systems 2. Use examples to describe the key transport mechanisms used by cells to absorb or remove specific substances (diffusion, facilitated diffusion and active transport) 2.1. Differentiate between active and passive processes 3. Define the following terms in relation to movement of molecules 3.1. Semipermeable membrane 3.2. Lipid soluble vs water soluble 3.3. Charged vs uncharged molecules (ionized vs non-ionized) 3.4. Solute 3.5. Concentration gradient 4. Define the following terms: isotonic, hypotonic, and hypertonic solutions 4.1. Explain what happens to water inside a cell when it is placed into solutions of different tonicity Read The plasma membrane is selectively permeable, it allows the passage of some ions or molecules but restricts the passage of others. This distinction is based on: Size and shape – larger molecules cannot directly cross through the phospholipid bilayer. Electrical change – changed molecules cannot directly cross through the phospholipid bilayer. Lipid solubility – water soluble molecules cannot directly cross through the phospholipid bilayer. Passage across the membrane is either: Passive – it results from the random motion and collisions of ions and molecules (kinetic energy). Active – energy expenditure, generally in the form of ATP, is required. Watch This recording reviews the key transport mechanisms used by cells to absorb or remove specific substances. (TLO T1C2)   Read Membrane transport is categorised according to the mechanism involved: Simple diffusion – the movement of a molecule directly through the phospholipid bilayer from an area of higher concentration to an area of lower concentration (until the concentration is the same on both sides of the membrane). Facilitated diffusion – the movement of an ion or molecule from an area of higher concentration to an area of lower concentration (until the concentration is the same on both sides of the membrane), via a channel or carrier protein. Osmosis – the movement of water molecules to an area of higher solute concentration, where the concentration of water is lower. Active transport – the movement of an ion or molecule from an area of lower concentration to an area of high concentration, via a channel or carrier protein. Diffusion rates are influenced by: Distance – the shorter the distance, the faster the diffusion. Molecular size – the smaller the molecule size, the faster the diffusion. Temperature – the higher the temperature, the faster the diffusion. Concentration gradient – the steeper the concentration gradient, the faster the diffusion. Electrical force – opposite electrical charges attract each other and like charges repel each other. Reference Lipid bilayer (https://commons.wikimedia.org/wiki/File:0303_Lipid_Bilayer_With_Various_Components.jpg) ,  OpenStax, CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/deed.en)   1.18 What is homeostasis? Topic 1D: Homeostasis 1. Explain the concept of homeostasis and its importance in the human body. 2. List the components of a homeostatic/regulatory mechanism, and use examples to demonstrate the role of each component (receptor, control centre, effector). 3. Use examples to describe how negative and positive feedback are involved in homeostasis. Read Have you ever wondered how your body ‘just knows’ when to stop eating when you’re full? When to start sweating when you’re hot? Why your breathing rate increases when you exercise? The answer to all these questions, and many more related to the maintenance of normal physiological parameters within your body can be explained by the concept of homeostasis – the body’s ability to maintain a stable (balanced) internal environment in the face of variable external conditions through constant interactions of the body’s many regulatory processes. In other words, homeostasis is your body’s ability to detect when something is out of balance, to process this information and to bring about changes that will restore balance. This is important because a constant state of balance (equilibrium) is required to keep us alive. Extended periods spent outside of homeostatic balances will lead to disease and eventually death if not corrected. For example, the normal levels of glucose in your blood sit somewhere between 70 – 110 mg/100 ml. This range is maintained through regulatory systems such as the interplay between insulin and glucagon (you will learn more about these hormones later in semester). If for some reason, your body is not able maintain your blood glucose levels within this range, then you will become hypoglycaemic (not enough glucose in the blood) or hyperglycaemic (too much glucose in the blood). If not corrected, hypoglycaemia will mean that your body cells cannot receive the glucose they require to make energy and function properly, eventually leading to shut down of organs and death; think starvation. On the other hand, chronic hyperglycaemia can also lead to disease and eventually death, think diabetes mellitus. So, you see, the ability to maintain homeostasis is essential to life. The concept of homeostasis underpins all the physiological processes that you will be learning about in the coming weeks. (TLO T1D1) Reflect How to use the documentation tool:  Type your response directly into the text fields below. Use the blue arrows to move between pages. Export your answers as a Word file to keep a copy of what you have written. You can use these responses to inform your critical reflection and personal reflective journal. Please note, your responses won't be saved in the system once you leave the page. You need to export your answer before you leave.   1.19 Control of homeostasis Read Image from vecteezy.com An aircraft pilot monitors all the dials in the cockpit and if any changes are detected, they will assess the situation and make appropriate adjustments to ensure that the plane continues to fly smoothly. The pilot in this instance will likely face several challenges from within or outside of the plane such as depleting fuel levels, changes in wind speed, outside temperature, cabin pressure, oxygen levels, etc. All of these, if left unchecked, will threaten to throw the aircraft off balance and it is the pilot’s job to recognise these deviations and act to restore balance. Similar to this scenario, our bodies are constantly facing homeostatic disruptions from both the internal (our cells; what’s inside them and what surrounds them) and external (outside of the body) environments and, just like the pilot, our bodies must first be able to detect the change, then we must be able to interpret or process the change before we respond to the change. This brings us to the next topic of homeostatic control. (TLO T1D1) Our bodies maintain homeostasis through regulating systems, namely the nervous system and the endocrine system. The nervous system maintains homeostasis by sending electrical messages called nerve impulses along the nerves to organs that can act to counter the change whereas the endocrine system does this via sending out chemical messages called hormones from the glands into the blood. Because the nervous system uses electrical impulses that travel directly to the effector organ(s) via the nerves, targeted and rapid responses are achieved but are typically short in duration. The endocrine system generally brings about a slower, more widespread and long-lasting response. Both systems work to ultimately maintain homeostasis, usually via negative feedback systems. (TLO T1D1, T1D2)   Practise Complete the following drag and drop activity. For each of the disruptions to homeostasis listed, identify whether they arise from the internal or external environment. Loading, please wait...  Negative feedback the response opposes the initial stimulus to reverse the change most homeostatic mechanisms are negative feedback mechanisms used in conditions that need frequent adjustments Eg, body temperature, blood sugar levels, blood pressure, blood calcium levels, blood pH, etc 9 | Australian Catholic University Negative feedback example: Thermoregulation Too hot Too cold 10 | Australian Catholic University Negative feedback: Regulation of blood calcium levels 11 | Australian Catholic University Take home messages Most of the homeostatic responses in the body use negative feedback loops Responses work in the opposite direction to the stimuli If something goes up, body acts to make it go down If something goes down, body acts to make it go up Negative feedback does not refer to the absolute direction of the response 12 | Australian Catholic University  The End 13 | Australian Catholic University Learning objectives Explain how the human body is organised Identify the major levels of organization in the body from the simplest to the most complex Identify the major components of each organ system Describe the location and function of body cavities  Body cavities Source:OpenStax College. Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/ References Martini, F., Nath, J.L., & Bartholomew, E.F. (2018). Fundamentals of anatomy and physiology (11th Global ed.) Pearson, Harlow, Essex, UK. Tortora, G.T., Derrickson, B.H., Burkett, B., Peoples, G., Dye, D., Cooke, J., Diversi, T., McKean, M., Samalia, L., & Mellifont, R. (2019). Principles of anatomy and physiology (2nd Asia-Pacific ed.) John Wiley & Sons, Milton, Qld, Australia. Learning objectives Explain how the human body is organised Identify the major levels of organization in the body from the simplest to the most complex Identify the major components of each organ system Describe the location and function of body cavities Levels of organisation – co-operative hierarchy Levels of organisation – co-operative hierarchy Chemical (or Molecular) Level Atoms - smallest chemical units of matter Molecules - a group of atoms working together Chemistry: Elements and macromolecules Elements Symbols = C, K etc Ions and electrolytes (e.g. Na+, K+, Ca2+) Macromolecules Functions Proteins Structure/form work Carbohydrates Storage Lipids/fats Messengers Nucleic acids Control Levels of organisation – co-operative hierarchy Cellular Level Cells - a group of atoms, molecules, and organelles working together Basic unit of life  Cells ~37.2 x 1012 cells ~50 billion fat cells ~2 billion heart muscle cells Cell numbers vary in health and disease More coming soon By Mediran - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=20664784 Levels of organisation – co-operative hierarchy Tissue Level Tissue - A group of similar cells working together  Tissues Four types of primary tissues 1. Epithelial tissue 2. Connective tissue 3. Muscle tissue 4. Neural tissue More coming soon CK-12 Foundation - Zachary Wilson, CC BY-NC-SA 3.0, https://www.ck12.org/book/ck-12-biology-advanced-concepts/section/17.2/ Levels of organisation – co-operative hierarchy Organ Level An organ - a group of different tissues working together  Organs Made up of different tissues Organ functions are supplied by tissues Multi-tasking E.g. Skeletal muscle Specialists E.g. Heart Image by brgfx on Freepik Levels of organisation – co-operative hierarchy Organ System Level An organ system is a group of organs working together Humans have 11 organ systems Organ Systems Functions Control/direct Cool and warm Digest Move Protect Remove Reproduce Store Support Transport (Martini, Nath and Bartholomew, 2018) Levels of organisation – co-operative hierarchy The Organism Level A human is an organism References Martini, F., Nath, J.L., & Bartholomew, E.F. (2018). Fundamentals of anatomy and physiology (11th Global ed.) Pearson, Harlow, Essex, UK. Tortora, G.T., Derrickson, B.H., Burkett, B., Peoples, G., Dye, D., Cooke, J., Diversi, T., McKean, M., Samalia, L., & Mellifont, R. (2019). Principles of anatomy and physiology (2nd Asia-Pacific ed.) John Wiley & Sons, Milton, Qld, Australia. Membranes Dr Jackie Stevens Membrane of the body Physical barriers that line parts of the body Consists of An epithelium Supporting connective tissue Types of membranes, OpenStax College, CC BY-SA 4.0 2 | Australian Catholic University Tissue level of organisation Tissues, OpenStax College, CC 3.0 2 | Australian Catholic University Epithelial tissue Lining, covering Functions: protection, absorption, filtration, excretion, secretion Classified by shape and number of layers Tissues, OpenStax College, CC 3.0 3 | Australian Catholic University Epithelial tissue, OpenStax College, CC 3.0 Connective tissue Functions Support and bind other tissues Provide insulation and protection Classified according to physical properties Connective tissue proper Fluid connective tissue Supporting connective tissue Tissues, OpenStax College, CC 3.0 4 | Australian Catholic University Muscle tissue Specialised for contraction Types Skeletal Smooth Cardiac Tissues, OpenStax College, CC 3.0 5 | Australian Catholic University Nervous tissue Primary function is communication Types Neurons (nerve cells) Neuroglia (support cells) Tissues, OpenStax College, CC 3.0 6 | Australian Catholic University