Heredity & Evolution PDF

11 0 WHAT YOU BUILD? WHAT YOU LEARN? Inheritance of traits from parents; Gene & Allele;...

11 0 WHAT YOU BUILD? WHAT YOU LEARN? Inheritance of traits from parents; Gene & Allele; Dominant, Co- dominant & Recessive gene; Change of dominant gene based on circumstances. WHAT IT IMPROVES? Conceptual Understanding Peer Learning LEARNING BY DOING NAME: ROLL NO.: CLASS: www.butterflyfields.com  Y_HEEV_110_V1/IOS Kit components to do 2 activities Table of Contents Type Time Page No. 1 What is Heredity? i 1 2 Where are genes located in the body? i 1 3 How are genes arranged in the chromosomes? i 1 4 When do you inherit two forms of a gene from your parents? i 2 What are the different possibilities of allele pairs possible 5 for each trait? i 2 6 Punnet square i 2 7 Activity 1: Genesis (Heredity) 30 min. 3 8 Natural selection i 5 9 Activity 2: Survival of the fittest 40 min. 5 10 Real life connect i 8 11 Self Assessment (10 marks) ? 5 min. 8 12 Concept map - Revise all the key concepts in one go 5 min. 9 Total 80 min Activity i Information ? Self assessment Concept Map Y_HEEV_110_V1/IOS i What is Heredity? Heredity is the passing down of traits from parents or ancestors. Some examples of observable traits are hair color, type of hair, size of eyes, type of ear lobes, etc. Traits in a living organism are controlled by Genes. Genes are the functional units of heredity that are found within all living cells. A gene can have different versions or forms. Each version or form of a gene is called an allele. Example: Gene Forms of the gene Q. Name any 1 trait passed on to you from your father & 1 trait from your mother. Hair color Black, brown, red etc. Type of hair Curly, Straight etc. Size of eyes Big, medium, small etc. Type of ear lobes Attached, Free etc. i Where are genes located in the body? Cells Nucleus 1 chromosome ~ 20,000 genes (DNA chain) Gene 23 pairs of Chromosomes Gene Human body is Each cell has a nucleus. made up of cells. Each nucleus has Each chromosome has (50,000,000,000,000 cells) chromosomes. genes located on them. i How are genes arranged in the chromosomes? Chromosomes in most cells of the human body exist in pairs. Every living organism has different number of chromosome pairs. Ex: Chimpanzee - 24 pairs of chromosomes, Banana - 11 pairs of chromosomes etc. Each chromosome pair has two forms of a gene (two alleles) for each trait inherited from both parents. Humans have 23 pairs of chromosomes in each cell Each pair of chromosome carries the same set of genes. An example is shown below. From Mother From Father Ear wax texture Ear wax texture BMI BMI Longevity Longevity Hair colour Hair colour Speech impediment Speech impediment Chromosome from Father Chromosome from Mother Chromosome pair-16 For help & additional things to try, visit www.butterflyfields.com/help/110 1 of 9  Y_HEEV_110_V1/IOS i When do you inherit two forms of a gene from your parents? We inherit genes from our parents during reproduction. Sperm cell (Male) Egg cell (Female) 1 set 1 set Most cells in the human body Sperm & egg cells - are special A fertilized egg gets 23 pairs of have 23 pairs of chromosomes cells with only 1 set of 23 chromosomes chromosomes The fertilized egg then multiplies through cell division over and over and over until it creates a child. The same 23 pairs of chromosomes in the fertilized egg gets copied to all the cells. i What are the different possibilities of allele pairs possible for each trait? Some alleles are expressed fully (dominant), while some are masked (recessive). After allele pairing, the trait expressed in the child can be known based on allele dominance. Example: Let us consider the trait - hair color & assume this trait is located on chromosome-16. P1, P2, P3, P4 are different forms of the gene (alleles) controlling hair color Assumption: P1 - Brown, P2 - Black, P3 - Brown, P4 - Black Father Sperm cell Child Chromosome pair-16 Allele pairing : 1 allele from each parent P1 (or) P2 P1 P2 When a sperm cell is created, Allele pairing : P1P2 it can get either P1 or P2 allele When an egg is fertilized, Hair colour: black - 2 possibilities alleles can pair in 4 possibilities Mother Egg cell Black allele is dominant to Brown allele Chromosome pair-16 (or) P3 P4 (or) (or) (or) P3 P4 P1 P3 P 2 P4 P1 P4 P 3 P2 When an egg cell is created, Allele pairing : P3P4 it can get either P3 or P4 allele Brown Black Black Black Hair colour: black - 2 possibilities i Punnet square A punnet square is a graphical way of predicting all possible outcomes of a breeding. Example: Using a punnet square to determine the sex of a child. Chromosome pair-23 contains the sex determining gene. Possible alleles: X - female & Y - male. Mother Mother Possible outcomes X X X X (Y allele is dominant to X) X X XX XX XX - Female - 2/4 - 50% Father Father Y Y XY XY XY - Male - 2/4 - 50% 2 of 9 For help & additional things to try, visit www.butterflyfields.com/help/110 Y_HEEV_110_V1/IOS Activity 1: Genesis (Heredity) Objective: Given the allele pairs of parent wolves involved in breeding, you have to predict the possible characteristics of the offsprings. Different forms of the genes controlling NOTE: Alleles represented with Tai l E ar Eye capital letters are dominant Long tail Big ears Big eyes T E Y Body of the wolf Short tail Small ears Small eyes e t y Note: The offspring are to be drawn on the tracing papers provided. The characteristics are to be traced from the reference sheet provided. Material Example: Parent 1: short tail(tt) big ears(EE) eyes(YY) Parent 2: long tail(TT) small ears(ee) eyes(yy) Steps for predicting traits in offsprings: 1) Find out all possible offspring combinations by drawing the punnet square Tail Ears Eyes Parent-2 Parent-2 Parent-2 t t e e y y T Tt Tt E Ee Ee Y Yy Yy Parent-1 Parent-1 Parent-1 T Tt Tt E Ee Ee Y Yy Yy Possible outcomes Tt Possible outcomes Ee Possible outcomes Yy Possible Offsprings combinations: Tt,Ee,Yy Observed traits in the offspring: T,E,Y (Long tail, Big ear, Big eye) (based on allele dominance) For help & additional things to try, visit www.butterflyfields.com/help/110 3 of 9  Y_HEEV_110_V1/IOS 2) Sketch the body of the wolves with all combinations found out in the punnet square 1 2 3 4 Exercise Parent 1: long tail(Tt) small ears(ee) eyes(Yy) Parent 2: short tail(tt) big ears(Ee) eyes(YY) Steps for predicting traits in offsprings: 1) Find out all possible offspring combinations by drawing the punnet square Tail Ears Eyes Parent-2 Parent-2 Parent-2 Parent-1 Parent-1 Parent-1 Possible outcomes: Possible outcomes: Possible outcomes: 1. 1. 1. 2. 2. 2. Possible Offsprings combinations 1. 2. 3. 4. 5. 6. 7. 8. ? Question What is a dominant allele? It is expressed as a trait. It is not expressed as a trait. It is not passed on to the child. All alleles are dominant. 4 of 9 For help & additional things to try, visit www.butterflyfields.com/help/110 Y_HEEV_110_V1/IOS 2) Sketch the body of the wolves with all combinations found out in the punnet square NOTE: Use 1 tracing paper to draw 2 offspring combinations i Natural selection Natural selection is the process by which traits become either more or less common in a population due to changes in their environment. Activity 2: Survival of the fittest Materials required: 5 Allele holders 80 Alleles Game board 1 die 4 Pawns Objective of the game: 1) How population of different colored monsters is affected due to changes in the environment? 2) How dominance within alleles affects the color of monsters over successive generations? Scenario: 1) An imaginary environment with a population of different colored monsters in it. 2) Changes in environmental conditions can affect the survival of some particular colored monsters. 3) You play God and create monsters of different colors by allele pairing such that your monster population survives the changes in the environment. Winning criteria - Survival of the fittest: The last player standing (with atleast 1 monster) wins the game! Representation: The transparent strips represent 4 different forms of a gene (Dark Green, Light Green, Brown and Violet) that controls one Monster trait - Skin Color. Different forms of the gene & their order of dominance: Dark Green Dominant Light Green Recessive Recessive Violet Brown Co-dominant For help & additional things to try, visit www.butterflyfields.com/help/110 5 of 9  Y_HEEV_110_V1/IOS The table below shows the resulting skin color of the monster in different allele pairings. Dark Green Light Green Violet Brown Dark Green Dark Green Dark Green Dark Green Dark Green Light Green Dark Green Light Green Light Green Light Green Violet Dark Green Light Green Violet Orange Brown Dark Green Light Green Orange Brown How to play - Level 1 1. Shuffle all alleles & distribute 20 alleles to each player Player-1 Player-2 Player-3 Player-4 2. Each player creates 10 monsters by pairing the 20 alleles. Use the gene dominance table to find the resulting skin color on pairing of different types of alleles. Keep the allele pairs formed into the allele holders. Example: Player-1 has x5 x4 x3 x8 Brown Violet Light green Dark green Player-1 creates 10 Monsters as below M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 Player-1 places monsters in allele holders based on their skin colour (Refer table above) Dark green Light green Violet Brown Orange 3. After all the players have created 10 monsters by allele pairing. Place pawns at the START. 4. Roll the dice to move forward 5. When you land on a block, remove alleles of monsters which are affected. Example: Player-1’s Orange and violet monsters affected by “Drought” 6 of 9 For help & additional things to try, visit www.butterflyfields.com/help/110  3. After all the players have created 10 monsters by allele pairing. Place pawns at the START. 4. Roll Y_HEEV_110_V1/IOS the dice to move forward 5. When you land on a block, remove alleles of monsters which are affected. Example: Player-1’s Orange and violet monsters affected by “Drought” Orange Remove alleles of orange and violet monsters from their holders 6. Continue playing the game in rounds, until only 1 player has atleast one monster remaining. Observation table - Level 1 Note down the current population of your monsters before every round An example is shown below: Dark Green Light Green Violet Brown Orange Total Example 5 1 2 2 0 10 Start Round-1 Round-2 Round-3 Round-4 Q. Can two dark green alleles pair up to form a light green monster? Yes No Q. Can one dark green allele and one light green allele pair up to form a light green monster? Yes No How to play - Level 2 The rules of the game in level-2 remain the same as level-1 except for addition of one new rule. New rule: Players get to re-pair their alleles before the start of each turn. Hint: Use the threats coming ahead in the game to plan your next generation of monsters Observation Example: table - Level 2 Player-1 has 8 monsters after round-1 Steps for filling up the obseration table: Remove all alleles to re-pair 1) Note down the current population of your monsters after every pairing 2) Strike off the type of monsters affected by catastrophes An example is shown below: Dark Green Light Green Violet Brown Orange Total Dark green Light green Example 5 1 2 Dark green 2 Light green 0 10 Pairing -1 Pairing-2 Pairing-3 Pairing-4 For help & additional things to try, visit www.butterflyfields.com/help/110 7 of 9  Y_HEEV_110_V1/IOS ? Fill in this table using your remaining monsters at the end of your game. Can you get the monster If there is a catastrophe that Why or why not? again by re-pairing the kills all your monsters of this colour Give your reasons. remaining alleles? No more dark Dark green Dark green (Yes/No) : No green alleles left Light green Light green (Yes/No) Violet Violet (Yes/No) Brown Brown (Yes/No) Orange Violet (Yes/No) ? Did you know? Fraternal twins Identical twins 1) Single fertilized egg splitting into two separate embryos. 1) When two eggs are independently fertilized by 2) Identical twins come from the same two different sperm cells, fraternal twins result. fertilized egg, they have the exact same set of 2) Like any other siblings, they usually have differ- chromosome pairs. ent set of chromosome pairs. 3) They are always of the same sex and they 3) They may be of different sexes or the same sex. have the same blood type. The study of genes & heredity is called Genetics, which allows us to understand different genes, their functions & how they are passed on to offsprings from parents. It's used in tracing down hereditary diseases, DNA fingerprinting to investigate crime suspects, & even selectively breeding of plants for better yields etc. ? Self Assessment 1) A Gene is present on a. Chromosome b. Nucleus c. Cell wall d. Mitochondria 2) A Chromosome is a. A string of genes connected together. b. Present outside the nucleus. c. Passed from either mother or father. d. Is present only in one cell in the human body. 3) Heredity is a. Passing of traits from parents to children. b. A type of chromosome. c. A type of gene. d. Only true for humans and not for animals. 4) Which of the following is NOT a possible allele pairing of a gene? Given: Trait - Type of hair; Forms of gene - Straight (S), Curly (C) a. CS b. CC c. SS d. SSC 5) What is the probability of an getting an offspring with attached ear lobe? Given: Trait - Type of ear lobe; Forms of gene - Attached (A), Free (F) Parent-1 allele pair: AF Parent-2 allele pair: AF a. 0 % b. 25 % c. 50 % d. 75 % 8 of 9 For help & additional things to try, visit www.butterflyfields.com/help/110  Y_HEEV_110_V1/IOS Gene location in human body Sperm cell (Male) Egg cell (Female) 1 set 1 set A gene is a molecular unit of heredity of a Gene living organism Most cells in the human Sperm & egg cells - are special A fertilized egg gets 23 body have 23 pairs of cells with only 1 set of 23 chromosomes pairs of chromosomes chromosomes Gene The fertilized egg then multiplies through cell division over and over and over until it creates a child. Gene Human Cell 1 Chromosome (DNA chain) Allele Each pair of chromosome carries the same set of Heredity is the passing of genes. An example is shown below. The same 23 pairs of chromosomes in the fertilized egg gets copied to all the cells. traits to offspring from its From Mother From Father parents or ancestor. Alleles are variations of Ear wax texture Ear wax texture 1) Equal contribution of genetic material genes. from both parents BMI BMI When do we inherit Definition Longevity Longevity 2) Some forms of the genes are domi- Hair colour Hair colour nant to other forms & are expressed fully Rules of inheritance Speech impediment Speech impediment DNA finger printing - Crime investigation Chromosome pair-16 Heredity Different possibilities of allele pairing Crime scene Study of genes is P1, P2, P3, P4 are different forms of the gene (alleles) Suspect-1 Suspect-2 Suspect-3 evidence called Genetics. controlling hair color Assumption: P1 - Brown, P2 - Black, P3 - Brown, P4 - Black Selective breeding of plants for desired traits (Black allele is dominant to Brown allele) Applications Gregor Mendel is considered of Genetics the fateher of Genetics Allele pairing: 1 allele from each parent Father Mother Mendel’s Pea plant Experiment P1 P2 P3 P4 Allele pairing : P1P2 Allele pairing : P3P4 F1(first yeneration all possible outcomes) F2(second yeneration all possible outcomes) Hair colour: black Hair colour: black Green pod Yellow pod Child Green pod Green pod GG yy y y Gy Gy G y y y (or) (or) (or) G G G y G y P1 P3 P2 P4 P1 P4 P3 P2 G Gy Gy G GG Gy Brown Black Black Black Gy Gy Gy Gy Gy Gy yG yy G GG yy Gy Gy y 9 of 9  Check out other Math Projects @www.butterflyfields.com Chemical reactions & equations - Conduct different types of chemical reactions (Displacement, Redox, Exothermic & Endothermic), Carbon & its compounds - Make structures of alkanes, alkenes, alkynes & functional groups, Life processes - Find concentration of CO2 in respiration, importance of valves in heart for circulating blood, Control & coordination - Trace neuron pathways for voluntary & reflex actions, different parts of the brain & their role, Heredity & evolution - Find behavior of genes - dominant & recessive during inheritance, factoring effecting natural selection, Human eye & colorful world - Simulate structure of the human eye, defects of vision & their correction, Electricity: Series & Parallel circuits - Verify Ohm's law in series & parallel circuits connected with bulbs, resistors & variable resistance (rheostat), Magnetic effects of electric current - Observe magnetic effect on compass when current passes through a conductor, Make a working DC motor REGISTER @ www.butterflyfields.com Get a SURPRISE GIFT Where are our ex-students? “Such innovative tools can Kinnera Priya – now in IIT Roorkee – BFF batch 2007-10 improve effectiveness of student learning.” Akshar Yadavalli – got admission for B.S from all IVY League colleges in USA – BFF batch 2008-12 Dr. APJ Abdul Kalaam appreciating the efforts of Rohan Aloor – now in Jindal Law School – BFF batch 2007-09 Butterfly Fields Subscribe to our channel Like our page Watch hundreds of project instruction videos at: Check out innovative project ideas at: 6,00,000 /TheButterflyfields /ButterflyFieldsIndia Students Students in these towns are now learning by doing! 4,000 Adilabad, Ahmedabad, Ambikapur, Armoor, Bangalore, Baroda, Bellare, Bhavnagar, Bijapur, Chanduluru, Chennai, Coimbatore, Cuddalore, Dharwad, Duliajan, Gangavaram, Gulbarga, Guntur, Guwahati, Schools Honnutagi, Hosur, Hyderabad, Kanpur, Karur, Kodagu, Kolkatta, Kothur, Krishnagiri, Kurnool dist, Madurai, Mahbubnagar, Morpi, Mumbai, Mysore, Nagpur, Narsaraopet, Nellore, Nizamabad, Noida, and growing... Nuzellapalli, Ooty, Paloncha, Pamidipadu, Panguluru, Pollachi, Pune, Ranebennur, Redlawada, Sandur, Sarapaka, Shimoga, Surat, Thane, Thanjavur, Thiruchengode, Tirupathi, Tumkur, Vijayawada, Visakhapatnam, Wadlakonda, Warangal, West Godavari, Zaheerabad Help Line: +91-40-30608888, 27711020. @ [email protected]