Dominant & Recessive

Transcription

1 Dominant & Recessive Questions you will be able to answer at the end of today: 1. Why do we not have people with half brown and half blonde hair? 2. What are the major dominant and recessive phenotypes? 3. Do you have more dominant or more recessive traits? This doesn't happen naturally! (Thank goodness...)

2 Warm Up: Inherited vs. Acquired, Genes & Alleles Make this chart: Physical: Inherited Traits vs. Acquired Traits Physical: Medical: 1. Behavioral/Instinct: 1. Medical: 1. Behavioral/Learned: 1. NOW FILL IT OUT WITH ANY HUMAN'S TRAITS use some of your own!

3 Things to Remember Babies inherit the ability to make lots of different noises and to mimic what they hear, but they ACQUIRE the language they speak! 2. Make up and clothing alone are NOT acquired traits using the makeup to change your appearance is closer so, saying "red lips from lipstick" or "long eyelashes from mascara" would be acquired. Saying your sense of style (instead of clothing) would be more of a learned behavior/preference which is linked to your ideas. 3. Some diseases ^it into both categories. Diabetes can be inherited or acquired from eating too much garbage food. Cancers can be in your genes or acquired like lung cancer from smoking, skin cancer from tanning, or other cancers from being around chemicals. 4. Beliefs, ideas, memories, thoughts, and things you know how to DO are often ACQUIRED playing a sport, a musical instrument, building something, learning how to read, write or do math all of this is LEARNED. 5. Instincts are inherited. So, a bird knowing where and when to migrate, a bear or bat hibernates, a lion hunts, you ^linch when something comes ^lying to your head these are all programmed in the DNA!

4 Discuss & Brainstorm 1. Which traits have genes that coded for them: inherited or acquired? 2. Brainstorm a list of 10 different genes that humans have for their physical traits. Gene Alleles a. :, b. :, c. :, d. :, e. :, f. :, g. :, h. :, i. :, j. :,

5 What we know so far... All traits in an organism Inherited Come from: Parents pass their genes to you! Genes have different variations called alleles. Everybody has the same basic genes, but we all have different combinations of alleles that make our behaviors, medical background and physical appearance different. Acquired Come from choices, experiences, environment, accidents, outside sources Are passed on only if they are taught to you, or you share a same experience/ culture/religion etc. NO GENES. NO ALLELES. Today's Big Question: SO... why is it that if you get an allele from each parent let's say one has black hair and the other has blonde... why don't you have BLONDE AND BLACK HAIR?

6 Some alleles are "bullies" that force the other alleles to HIDE! Gene: Hair Color. Alleles:, BULLY? HIDES? Gene: Eye Color. Alleles:, BULLY? HIDES?

7 Alleles that BULLY and are ALWAYS SEEN IF YOU HAVE AT LEAST ONE OF THEM are called Alleles that HIDE and are only seen if there ISN'T a BULLY AT ALL are called...

8 Word connections... Dominant 1. Watching sports... "That team is really DOMINATING!" 2. That dog is dominant. 3. This trait steps up and is all action! Recessive 1. A wall pushed back, like a door in the classroom, is called "recessed." The wall sticks out farther than it does, so it kind of hides. 2. Recessed traits kind of stand back and let the dominant do it's thing.

9 Are you Dominant or Recessive? 1. Weave your ^ingers together naturally. Describe which thumb ends up on top. DOMINANT is: recessive is: 2. Flex your ^ingers can you bend them at each joint? DOMINANT is: recessive is: 3. Stick out your tongue. Now try to roll it. Can you, or does it stay ^lat? DOMINANT is: recessive is:

10 PHENOTYPES: What you PHYSICALLY SEE Dominant & Recessive Traits Underline, highlight or circle all of YOUR traits! Eye Color Vision Hair Facial & Body Features Other brown eyes Dominant farsightedness, normal dark hair non-red hair curly hair full head of hair widow's peak dimples unattached/lobed/ hanging earlobes freckles broad lips oval face shape cleft chin broad eyebrows separated eyebrows long eyelashes almond shaped eyes ability to roll tongue straight thumb interlaced fingers, L top double jointed second toe shorter than big toe normally pigmented skin normal blood clotting normal hearing normal hearing and speaking Recessive grey, green, hazel, blue normal, nearsighted, night blindness, color blindness blonde, light hair red hair straight hair baldness normal hairline no dimples attached earlobes no freckles thin lips square face no cleft chin thin eyebrows unibrow short eyelashes round eyes no tongue rolling hitchhiker thumb interlaced fingers, R on top not double jointed second toe equal to or longer than big albinism hemophilia congenital deafness deaf mutism

11 Dominant & Recessive Phenotypes Allele 1 Allele 2 Allele 1 Allele 2

12 DOMINANT TRAITS: The Phenotypes!

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16 Recessive Traits: The Phenotypes!

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19 What we are drawn to: Combinations of Dominant with ONE strong Recessive Trait, or Rare Combinations we don't often see!

20 PHENOTYPES: What you PHYSICALLY SEE Dominant & Recessive Traits Underline, highlight or circle all of YOUR traits! Eye Color Vision Hair Facial & Body Features Other brown eyes Dominant farsightedness, normal dark hair non-red hair curly hair full head of hair widow's peak dimples unattached/lobed/ hanging earlobes freckles broad lips oval face shape cleft chin broad eyebrows separated eyebrows long eyelashes almond shaped eyes ability to roll tongue straight thumb interlaced fingers, L top double jointed second toe shorter than big toe normally pigmented skin normal blood clotting normal hearing normal hearing and speaking Recessive grey, green, hazel, blue normal, nearsighted, night blindness, color blindness blonde, light hair red hair straight hair baldness normal hairline no dimples attached earlobes no freckles thin lips square face no cleft chin thin eyebrows unibrow short eyelashes round eyes no tongue rolling hitchhiker thumb interlaced fingers, R on top not double jointed second toe equal to or longer than big albinism hemophilia congenital deafness deaf mutism

21 Illustrating the Traits in an Ultimate Person! DOMINANT PORTRAIT recessive portrait Must include: DOMINANT recessive 1. Face shape: 2. Chin shape: 3. Hair texture: 4. Eye shape: 5. Lip shape: 6. Dimples/none: 7. Freckles/none: 8. Eye color: 9. Hair color: 10. Ear shape: 11. hairline:

22 Dominant & Recessive Traits All of my Traits: Physical, Medical, Behavioral Acquired Traits: My Dominant Traits (aka my phenotypes) Inherited Traits: My Recessive Traits (aka my phenotypes) Your homework: Tonight, go home and interview someone you live with. Predict how many dominant and recessive traits you share with them. Then go over your dominant and recessive checklist and mark what they have. Compare it and contrast it to your own. How many dominant were similar? Recessive? How many traits were different? Was it as you expected? If you can, do this with someone biologically related to you-- a sister, mom, dad, uncle, cousin, niece, nephew, etc. if you don't live with biologically, your prediction might be a little different, but try it anyway!

23 Day 2: Dominant, Recessive & Genotype Questions you'll be able to answer: 1. Why do dominant traits win? Why are they dominant? 2. How can I represent the dominant and recessive traits that are in my genes/dna? 3. What is the relationship between genotype and phenotype? 4. Is my genotype related my inherited, acquired traits, both or neither? 5. Is my phenotype related to my inherited, acquired traits, both or neither?

24 Dominant & Recessive Analogies

25 Why is Dominant... Dominant? Where can we trace back the original humans? What are the actual phenotypes of many of those original humans? So, why are the dominant traits... dominant? (Soon we'll get to where the recessive traits came from!)

26 Introducing: Genotype! Prior Knowledge: We know that our original phenotypes were caused by our genes (DNA). So, if we are describing what we LOOK like, we say phenotype (because, remember, that can change if we do something to ourselves). BUT, if we are describing the GENE that CAUSED the way we look, we call that the GENOTYPE. It is an easy word to remember: your genotype is the TYPE OF GENE you have. We usually use a CODE to represent our genotypes. Dominant Gene: coded Recessive Gene: coded Since you get genes for each trait (one from each ), your genotypes could be..., or. (coded ) (coded ) (coded )

27 Each Gene (which leads to an inherited trait) Many Alleles Dominant Alleles * Represented by * In the genotypes hh, hh, or HH the alleles that are dominant are * Dominant alleles are always " " if there's just one! Examples of Phenotypes Recessive Alleles * Represented by * In the genotypes hh, hh or Hh, the alleles that are recessive are the * Recessive alleles always unless alleles are recessive: hh Examples of Phenotypes

28 Each Gene (which leads to an inherited trait) Many Alleles Dominant Alleles * Represented by UPPERCASE LETTERS * In the genotypes hh, hh, or HH the alleles that are dominant are the BIG H's. * Dominant alleles are always "expressed" if there's just one! Examples of Phenotypes 1. brown hair 2.brown eyes 3. dimples 4. freckles 5. cleft chin 6. widow's peak 7. unattached earlobes 8. full lips 9. almond shaped eyes 10. oval face 11. dark skin Recessive Alleles * Represented by lowercase letters * In the genotypes hh, hh or Hh, the alleles that are recessive are the little h's. * Recessive alleles always HIDE unless both alleles are recessive: hh Examples of Phenotypes 1. blonde/red hair 2. hazel/blue/green/grey eyes 3. no dimples 4. no freckles 5. no cleft on chin 6. straight hairline 7. attached earlobes 8. thin lips 9. round eyes 10. square face/jaw 11. light skin

29 Practicing the Genotypes and Phenotypes 1. Fill out the chart Phenotype Dominant or Recessive Allele? Genotype? A. Blonde hair B. Brown eyes C. Straight hair D. Red hair E. Square jaw F. Dimples G. Round eyes H. Black hair I. Straight hairline J. No freckles K. Freckles L. Blue eyes M. Attached earlobes N. Full lips O. Curly hair P. Widow's peak 2. Now imagine that each parent gave you a trait. Tell if each is dominant or recessive, then write the genotypes. A. Mom gives you the allele for widow's peak, and so does dad. Circle 1: Mom: Dominant or Recessive? Dad: Dominant or Recessive? YOUR Genotype: B. Mom gives you the allele for hazel eyes, dad gives you the allele for brown eyes. Circle 1: Mom: Dominant or Recessive? Dad: Dominant or Recessive? YOUR Genotype:

30 Review: What causes the way you look? Below, 1. Write a short de^inition, give 2 3 examples, OR draw a small picture to represent what each word means. 2. write a couple sentences that explain this word map. Gene/DNA/Allele Environment/ Choice/Experience Genotype Inherited Traits Acquired Traits Phenotype

31 More Resources if Necessary

32 Reviewing Inherited Traits: Genes & Alleles You get two copies of each gene one from each. Your parents can each give you the same gene, or can each give you different genes. The different types or variations of genes are called. An allele that is "strong" or is always seen is called a allele. It is represented by a letter that is always. An allele that you are the carrier for, but isn't shown (think of it as hiding) is called a allele, and it is represented by a letter that is always. The recipe for each gene, written in letter code like this: HH, hh, Hh, or hh is called the of an organism. We call it that because it shows the type of genes you have!

33 Inherited Traits: Genes & Alleles You get two copies of each gene one from each parent. Your parents can each give you the same gene, or can each give you different genes. The different types or variations of genes are called alleles. An allele that is "strong" or is always seen is called a dominant allele. It is represented by a letter that is always capitolized. An allele that you are the carrier for, but isn't shown (think of it as hiding) is called a recessive allele, and it is represented by a letter that is always lowercase. The recipe for each gene, written in letter code like this: HH, hh, Hh, or hh is called the genotype of an organism. We call it that because it shows the type of genes you have!

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35 DNA Gene Allele Inherited Traits Acquired Traits Dominant Allele Recessive Allele Genotype Genotype Phenotype Phenotype Homozygous Heterozygous Homozygous Heterozygous * From environment, choices, experience * Not passed on, therefore not genetic! * Ex: scars, tattoos, holes in ears from gages or piercings, thoughts, ideas, memories, knowledge, dyed hair, lung cancer from smoking, a tan from being in the sun, skin cancer, diabetes from having a terrible diet, depression from trauma. Passed on to you by ancestors, you may pass them on to your children! Natural hair color, eye color, behavioral tendencies, medical conditions. A variation of a gene that doesn't hide and is always expressed like dimples. A variation of a gene which can hide behind a dominant allele and is only seen if two recessive alleles are present. A variation, type or speci^ic type of gene. BROWN vs. BLUE are eye color alleles. Represented by an uppercase/capital letter like E for a dominant eye color allele. Represented by an lowercase letter like e for a recessive eye color allele. Allele pairing EE Allele pairing ee or Ee, big is dominant. Allele pairing ee Allele pairing ee or Ee, little is recessive. Phenotype Phenotype The actual trait we see! The actual trait we see! The actual trait we see!the actual trait we see! Brown Eyes Brown Eyes Blue Eyes Brown Eyes Section of DNA that is the recipe for a speci^ic trait