National 5 Biology Multicellular Organisms Unit Success Criteria Success Criteria Multicellular Organisms National 5 Colour the box at the side of each objective: RED I don t know much about this or am confused by it. AMBER I know a bit about this but do not feel I know it well. GREEN I am very confident that I know this 1. Cells, tissues and organs 1. Understand that a multicellular organism is one which is made up of many cells. 2. Know that specialisation of cells occurs in multicellular organisms. 3. State that specialisation of cells in plant and animals leads to the formation of tissues and organs. 4. Understand that groups of organs work together to form systems. 2. Stem cells and meristems 1. Know that stem cells in animals are cells which can divide. 2. Understand that stem cells in animals have the potential to become different types of cells. 3. State that stem cells are involved in growth and repair. 4. Understand that meristems are sites of production of non-specialised cells in plants. 5. Know that meristems are the sites of mitosis in a plant cell. 6. Understand that non-specialised cells have the potential to become other types of plant cell. 7. Know that non-specialised cells contribute to plant cell growth. 5. Know that growth is defined as an irreversible increase in dry mass.
8. Identify the medulla on a diagram. 3. Control and communication a) Nervous Control 1. Understand that internal communication is required for survival of a multicellular organism. 2. Know that the nervous system is made up of the brain, spinal cord and nerves. 3. Know that the central nervous system is made up of the brain and spinal cord. 4. Identify the cerebrum on a diagram. 5. Know that the cerebrum is responsible for mental processes such as memory, reasoning, imagination, conscious thought and intelligence. 6. Identify the cerebellum on a diagram. 7. Know that the cerebellum is responsible for controlling balance and muscle coordination. 9. Know that the medulla is responsible for controlling the rate of breathing and heart beat. 10. State that the central nervous system sorts out information it receives from the sense organs (eyes, ears, skin etc). 11. State that the central nervous system responds to sensory information by sending messages to muscles and glands to carry out the appropriate responsive action. 12. Know that neurons carry information from the senses to the central nervous system, and from the central nervous system to the muscles or glands. 13. Identify the three types of neurones; sensory, relay and motor. 14. Understand that receptors in the skin, eyes, ears etc detect sensory input/stimuli. 15. State that electrical impulses move along neurones. 16. Know that a synapse is a tiny space between the ending of 1 neurone and the sensory fibre of the next.
16. Understand that a synapse allows chemicals to transfer from 1 neurone to another. 17. Know that a response to a motor neurone in a muscle (a contraction) may be rapid. 18. Know that the secretion of a hormone from a gland is a much slower response that that of a muscle cell contracting. b) Neurons and reflex arc 19. Know that the nervous system is made up of nerve cells called neurons. 20. Know that a neurone is made up of a cell body attached to nerve fibres. 21. Know that a reflex action is a rapid involuntary response. 23. Identify a diagram of a reflex arc. 24. Describe how a reflex arc works: (i) Stimulus is detected by the nerve endings in the receptor (e.g. skin), and converted to an electrical impulse. (ii) The electrical impulse is carried towards the cell body of a neuron by a sensory fibre. (iii) In the grey matter of the spinal cord, the impulse crosses the 1 st synapse. (iv) The electrical impulse passes through a relay neuron and then across a 2 nd synapse. (v) The nerve impulse is then picked up by the motor neuron and quickly conducted to the axon endings. (vi) A chemical is released which brings about muscular contraction. 25. Know that transmission of a nerve impulse through a reflex arc, results in a reflex action. 22. Understand that a reflex action has a protective function.
c) Hormonal control 26. State that hormones are chemical messengers. 27. Know that endocrine glands release hormones into the blood stream. 28. Know that target tissues have cells with receptor proteins for hormones. 29. Understand that only some tissues are affected by each hormone. 34. State that glucagon is a second hormone secreted by the pancreas. 35. Know that glucagon converts glycogen to glucose. 36. Understand that the action of glucagon increases the blood glucose level. 37. Understand the relationship between insulin and glucagon in maintaining a steady blood sugar level. d) Control of blood sugar levels 30. Know that insulin is a hormone made by the pancreas. 31. Understand that insulin converts excess glucose into glycogen. 32. Know that glycogen is stored in the liver. 33. State that the conversion of glucose to glycogen lowers blood glucose levels.
4. Reproduction 1. Understand that cells which have 2 matching sets of chromosomes are referred to a diploid. 2. Know that normal body cells are diploid. 3. Understand that cells with a single set of chromosomes are referred to as haploid. 4. Know that gamete is the collective term for sex cells. 5. Know that gametes are haploid. 6. Understand that pollen is the male gamete in plant cells. 7. Know that anther if the plant produced pollen. 8. Understand that an ovule is the female gamete in plant cells. 9. Know that the ovule in a plant can be found in the ovary. 10. Identify the reproductive parts of a plant in a diagram. 11. Know that in animals the male gametes are called sperm. 12. Understand that sperm are produced in the testes. 13. Identify the male reproductive organs of an animal in a diagram. 14. Understand that in animals the female gametes are called eggs. 15. Know that in animals the eggs are produced in the ovaries. 16. Identify the female reproductive organs of an animal in a diagram. 17. Understand that during fertilisation the nuclei of the male and female gametes fuse. 18. Know that fertilisation results in the production of a diploid zygote.
5. Variation and inheritance 1. Know that variation of characteristics exists within a population. 2. Understand that the fusion of gametes from separate parents increases variation in a population. 3. Know that a characteristic can be described as showing discrete variation if members of a population can be divided into 2 or more separate groups. 4. State that data gathered from a survey of discreet variation would be presented as a bar graph. 5. Give examples of discreet variation. Such as: hair type in humans, eye colour in fruit fly, flower colour in plants. 6. Know that a characteristic can be described as continuous variation when it varies amongst the population in a smooth continuous way from one extreme to the other, without falling into distinct groups. 7. Understand that results of a study on variation of a continuous characteristic would be presented as a line graph. 8. Give examples of continuous variation. Such as: a persons height or hand span over time in humans, body length in trout or mass of fruit in apple trees. 9. Know that a gene is a section of a chromosome which codes for 1 characteristic. 10. Understand that an allele is the different versions of a gene which are available. 11. State that the term phenotype refers to an organisms physical appearance in relation to any given characteristic.
12. Understand that if an individual possesses 2 identical alleles for 1 characteristic they are said to be homozygous or true breeding. 13. Know that if an individual possesses 2 alleles for a characteristic which are not identical to each other, they are said to be heterozygous. 14. Understand the symbols used when doing a genetic cross, P 1 is the parental generation, F 1 is the 1 st generation of offspring, F 2 is the 2 nd generation of offspring. 15. Know that if an allele always presents itself in the phenotype when present, it is said to be dominant. 16. Understand that some alleles will be masked by other versions of the gene, and the version of the characteristic they code for will skip generations, in this case the allele is said to be recessive. 17. Know that when doing genetic crosses each allele is assigned a letter. 18. Understand that the 1 st letter of the dominant characteristic is normally used (For example if red was the dominant flower colour and white the recessive, the letter r would be used to represent each allele in a genetic cross). 19. Know that the upper case letter is always used for the dominant characteristic (R = red) and the lower case for the recessive characteristic (r = white). 20. Understand that as each body cell has 2 allele s for each gene, the genotype is represented by 2 letters per gene. 21. Understand that as a gamete has half the genetic content of a normal body cell, it will only have 1 allele for the gene and is therefore represented by only 1 letter. 22. Know that most characteristics are coded for by more than one gene, and are said to be polygenic. 23. Know that most features of an individual phenotype are polygenic and show continuous variation. 24. Carry out a monohybrid cross from parents through to F 2 generation. 25. Know that if a homozygous dominant parent is crossed with a homozygous recessive, all of the F 1 will be heterozygous, and the resulting F 2 should give a 3:1 ratio of dominant:recessive characteristics.
26. Understand that expected ratios in a genetic cross are not always achieved, as fertilisation is a random process, or the sample size may be too small. 6. The need for transport a) Plant transport systems 1. Understand that a plant needs water for both photosynthesis and to transport materials around the plant. 2. Identify the structures involved in transporting materials around a plant (xylem and phloem) in a diagram. 3. State that water and mineral salts are carried from the roots to the leaves in xylem vessels. 4. Understand that xylem vessels are dead and contain lignin for support. 5. Know that movement of water in a plant occurs by osmosis into root hair cells. 6. Know that transpiration is the evaporation of water from the aerial parts of a plant. 7. Understand that transpiration occurs through tiny pores in the leaves called stomata. 8. Know that the opening and closing of the stomata is controlled by guard cells. 9. Know that guard cells are sausage shaped and contain chloroplasts. 10. Understand that the inner walls of the guard cells are thicker and less elastic than the outer walls which allow the 2 inner walls to be pulled apart when the guard cells become turgid. 11. Know that a leaf has a transparent epidermis which lets light through and has a protective function. 12. Understand that mesophyll cells (palisade and mesophyll) are layers of green cells which take in carbon dioxide and give out oxygen during photosynthesis. 13. Identify the various leaf structures in a diagram to include the upper epidermis, palisade mesophyll, spongy mesophyll, vein, lower epidermis, guard cells and stomata.
14. Know that phloem tissue is composed of sieve tubes and companion cells. 15. Understand that the phloem cells transport sugar around the plant. 16. State that phloem cells are living tissue. 17. Identify phloem cells in a diagram. b) Animal transport and exchange systems 18. Know that in mammals, nutrients, oxygen and carbon dioxide are transported in the blood. 19. Understand that the circulatory system consists of the heart and blood vessels. 20. Identify the structures of the heart in a diagram: the 4 chambers and the position of the valves. 21. Know that blood leaves the heart in arteries, flows through capillaries and returns in veins. 22. Describe the pathway of blood through the circulatory system: (i) Deoxygenated blood from the body enters the right atrium by the main vein called the vena cava. (ii) The right atrium contracts, pumping blood into the right ventricle. (iii) Contraction of the muscular ventricle wall forces blood into the pulmonary artery. (iv) The blood is then carried to the from the heart to the lungs where it picks up oxygen and becomes oxygenated. (v) The pulmonary vein returns oxygenated blood from the lungs to the heart s left atrium. (vi) The blood is then pumped into the left ventricle where strong contractions force it into the main vein called the aorta. (vii) The aorta takes the blood to respiring body tissues to drop off oxygen and once again become deoxygenated. 23. Know that an artery has a thick muscular wall to withstand the high pressure of oxygenated blood coming from the heart. 24. Know that the wall of the vein is thinner than the heart, so it has valves to prevent backflow of blood and its function is to carry blood towards the heart.
25. Understand that as an artery moves away from the heart, it divides into smaller vessels and finally into a dense network of thin-walled capillaries. 26. Know that capillaries form a large surface area to allow efficient gas exchange. 27. Describe the features of the capillaries which make it suited to gas exchange: (i) Thin walls only 1 cell thick (to allow rapid diffusion). (ii) Present large surface area allows them to be in close contact with the living cells in tissues and organs. 28. Know that as capillaries move away from body tissues they unite to form larger vessels that converge to form veins. 29. Understand that the 1 st branch of the aorta leaving the heart is called the coronary artery. 30. State that the coronary artery supplies the muscular wall of the heart itself with oxygenated blood. 31. State that red blood cells contain haemoglobin and are specialised to carry oxygen. 32. Describe the specialisation of red blood cells: (i) Biconcave in shape to increase surface area. (ii) No nucleus to increase surface area (which also means they contain no genetic material). (iii) Contains haemoglobin which binds with oxygen to form oxyhaemoglobin. 33. Know that the lungs in a mammal are where gaseous exchange takes place. 34. Describe the pathway of air as it enters the respiratory system: (i) Enters in the mouth and nose. (ii) Passes to the trachea. (iii) Trachea splits into 2 narrower tubes called the bronchi, 1 bronchus going to each lung. (iv) Each bronchus divides many times into bronchioles. (v) Bronchioles end in alveoli. 35. Understand that rings of cartilage keep the main airways open.
36. Know that oxygen and carbon dioxide are exchanged through the walls of the alveoli. 37. Describe the features of the alveoli which make it efficient at gas exchange: (i) Large surface area. (ii) Good blood supply. (iii) Thin walls for rapid diffusion of gases. 38. Understand that the walls of the trachea and bronchi are lined with cilia and cells which secrete mucus. 39. State that the mucus traps dirt and micro-organisms. 43. Understand that villi are finger-like projections found in the small intestine. 44. Know that the villi aid the absorption of the products of glucose and amino acids. 45. Describe the structure of the villi and how it is suited to its role in digestion: (i) Thin walled to allow rapid absorption. (ii) Present large surface area. (iii) Excellent blood supply to absorb nutrients. 46. Identify the structures within a villi in a diagram: the epithelium, blood capillaries and lacteal. 47. Know that the lacteal absorbs fatty acids and glycerol. 40. State the cilia beat back and forth pushing the mucus away from the lungs. 41. Know that food is moved through the digestive system by peristalsis. 42. Describe the mechanism of peristalsis: Muscles BEHIND the food CONTRACT, muscles IN FRONT of food RELAX.
8. Effects of Lifestyle Choices 6. State that poor lifestyle choices can increase the chances of health problems including: 1. State that an individual has physical and mental aspects of health. 2. State that healthier lifestyle choices can improve an individuals health. fatty deposits in blood vessels blood clots heart attacks strokes diabetes stress high blood pressure 3. Identify that healthier lifestyle choices include: regular exercise a balanced diet socialising with friends relaxation activities 4. State that poor lifestyle choices can have a negative effect on health. 5. State that poor lifestyle choices include: high fat diet high salt diet lack of exercise smoking tobacco excess alcohol intake high stress experiences 7. State that a lack of iron means haemoglobin cannot be made and can lead to anaemia. 8. State that environmental factors can damage health. 9. State that environmental factors include: Heavy metals Radiation Pollution 10. State that heredity plays a part in the incidence of some conditions. 11. State that physiological measurements can be used to measure health. 12. Carry out physiological measurements including: pulse rate breathing rate temperature blood pressure