Types of variation


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2. Differentiate the types of variations Illustrate the variations noted in the specimen and, Appreciate the beauty and wonders of the things around brought by the types of variations OBJECTIVES 3. variation basic quality of an organism phenotype an individuals observable trait (height, eye color, and blood type) genotype genetic contribution of the phenotype; a collection of genes; a combination of alleles for a particular gene 4. GENOTYPIC VARIANCE variation in phenotype caused by genetic make-up additive variance (deviation from mean phenotype due to inheritance of a particular allele; average differences) dominance variance (expression is not equal) epistatic variance (interaction with alleles but associated with different loci) ENVIRONMENTAL VARIANCE specific environmental variance (deviation from mean due to envt conditions uniquely experienced by individual) general environmental variance (non-genetic sources experienced by multiple individuals in population) genotype by environment interaction (unique or diff responses of genetic lines to GEV) MAJOR CAUSES OF VARIATION 5. In a CORN, genes A and B control the yield of the corn. A 2 corns a 1 corn B 6 corns b 3 corns each allele will contribute to the yield of the corn AaBb X AaBb AABB - 16 (2+2+6+6) AABb - 13 AABb - 13 AaBB - 15 Aabb - 9 AaBb - 12 aaBB - 14 aabb - 8 aaBb - 11 ADDITIVE VARIANCE 6. A plant produces white flowers if its genotypes are A1A1 and red flowers if its genotypes are A2A2 we would assume that A1A2 leads to pink flower but in dominance variance there is NO MIDPOINT If A2 is dominant, A1A2 would produce red flowers DOMINANCE VARIANCE 7. In the same flower, a B1 gene produces pigment whereas a B2 gene does not produce any pigment (flower appears white) A2A2B1B1 red flower A1A1B2B2 white flower A2A2B2B2 white flower EPISTATIC VARIANCE 8. 5 pcs common fruit belonging to same species 5 pcs mayana, San Francisco, or Duranta leaves 5 pcs flowers of any plant species 2 groups of 5 invertebrates Drawing materials and coloring pens ruler MATERIALS 9. A. Variation in plants Examine the 5 fruits, the 5 leaves and the 5 flowers of the plant specimens that you brought. Note the variations in size, shape, color, and their other features. Illustrate and list down at least 5 variations that you have observed in each of the specimens. Compute for the total magnification of each specimen. PROCEDURE 10. B. Variations in animals Do the same in your animal specimens. Observe not only its morphological or anatomical variations but also their similarities and differences physiologically, behaviorally and sexually. Compute for the total magnification of the specimen. All drawings must be of 50 mm. in length and in width. Computations about reduction and magnification must be included. Determine if the specimen is magnified or reduced. PROCEDURE 11. Name Date Course/Yr/Section Types of Variation A. In Plants 1. Fruits of (illustrations) Similarities Differences 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. FORMAT 12. Types of Variation 2. Leaves of (illustrations) Similarities Differences 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. Computations of magnification: FORMAT 13. Types of Variation 3. Leaves of (illustrations) Similarities Differences 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. Computations of magnification: FORMAT 14. Types of Variation B. In animals 1. (Common name: _________) (illustrations) Similarities Differences 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. Computations of magnification: FORMAT 15. Types of Variation B. In animals 2. (Common name: _________) (illustrations) Similarities Differences 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. Computations of magnification: FORMAT 16. 1. What is variation. Give its importance. 2. What are the possible causes of variations? Give specific examples. 3. How would you know or identify if the cause of variation is genetic, environmental, or both? 4. Classify these variations as to species characteristics or individual characteristics. Thorns in the stalk of the rose flower Body size of ants Color of apple skin Color mosaic in San Francisco leaf Number of body segments in worm QUESTIONS 17. Make a survey of at least ten 2nd or 3rd year college students. Note their sex, age, height, weight, and thumbprint. Fill out Table 1 With the guide, classify the different surveyed thumbprints. Summarize the data gathered on age, height and weight and complete Table 2 Make a list of twenty (20) human traits and classify them as to morphological, physiological, sexual or behavioral variations. Fill out Table 3. CONT. HUMAN VARIATIONS 18. FINGER PRINT CLASSIFICATION 19. Start collecting wild-type fruit flies Place banana or its peel in a jar and expose near a garbage can. Observe frequently until enough fruit flies are trapped in the jar. Cover with paper and poke the paper with pin (enough to produce air circulation) Secure the paper with rubber band. Do not keep in locker or expose in direct sunlight. Keep in room temperature. Keep collecting for culturing. REMINDERS 20. Bring: Samples of the fruit fly. Hand lens cotton balls scissor scotch tape face mask NEXT MEETING