C-Notes: Modern Genetics Stnd: 2g C-Notes: Modern Genetics 1/15/2014 Objective: SWBAT identify how certain combinations of alleles form the genetic make-up of an individual.

The passing of traits from parent to offspring. The study of heredity. The passing of traits from parent to offspring. Are characteristics that can be passed from generation to generation. Ex: Same hair color, eye color, or skin color. What is Genetics? What is Heredity? What are Traits? Certain drugs have become popular among teens and young adults at dance clubs and raves.

What are Alleles? What is Dominant? What is Recessive? For every trait a person have, two forms of a genes will determine how that trait is expressed. We use letters to represent alleles, since every gene has two alleles , all genes can be represented by a pair of letters. Two types of Alleles Dominant Recessive stronger of two genes expressed in a trait; always expressed regardless of what other allele it is paired with represented by a capital letter (R) Ex: Tallness is a Dominant trait in height Weaker of the two genes expressed in a trait, only expressed when paired with another recessive allele in a cross. represented by a lowercase letter (r) Ex: Shortness is a recessive trait in height   Certain drugs have become popular among teens and young adults at dance clubs and raves.

All traits are expressed with TWO Alleles Ex: Tongue rolling T= Able to tongue roll (TT & Tt) t= Not able to tongue roll (tt) TT Tt tt Certain drugs have become popular among teens and young adults at dance clubs and raves.

What is Homozygous (true-breeding)? What is Heterozygous? When the two alleles are the same Ex: TT or tt homozygous individual could be capital or lowercase, as long as they are the same. Ex. AA, bb, EE, dd When the two alleles are different, in this case the DOMINANT allele is expressed. Ex: Tt ,Pp, Aa Certain drugs have become popular among teens and young adults at dance clubs and raves.

What are Genotypes? What are Phenotypes? Are genes, genetic instruction, letters for that particular trait the organism have. Ex: TT, Tt, tt The physical appearance (What the organism look like) for that particular trait. ex: tall, short, brown hair, blonde hair, blue eyes, brown eyes. **Genotypes are genetic instruction, which are represented by letters (TT, Tt, and/or tt) for the physical appearance , ex: eye color, height, etc. (Phenotypes) for the organism. **Cannot always determine genotype by observing phenotype** Certain drugs have become popular among teens and young adults at dance clubs and raves.

C-Notes: Gregor Mendel Stnd: 3b C-Notes: Gregor Mendel 1/15/2014 Objective: SWBAT identify the genetic basis for Mendel’s law of segregation and independent assortment.

He was known as the “Father of Genetics” Discovered how traits were inherited Who was Gregor Mendel? Block 2

Why did Mendel use Pea Plants as his Experimental Subject? Because they were easy to study and showed a variety (many) of contrasting traits. Ex: Purple vs white flowers Tall vs short stems Round vs wrinkled seeds. Pea plants are able to cross pollinate and self-pollinate. Certain drugs have become popular among teens and young adults at dance clubs and raves.

What is Cross-Pollination? Involves the fertilization of two parents Which results in a Hybrid offspring where the offspring may be different than the parents. Certain drugs have become popular among teens and young adults at dance clubs and raves.

What is Self-Pollination? The fertilization of one parent (flower) as both parents natural event in peas Results in Pure-Bred offspring where the offspring are identical to the parents. Certain drugs have become popular among teens and young adults at dance clubs and raves.

Why was it important that Mendel’s work in genetics began with purebred (truebred) plants? Self pollination of purebred plants always produces offspring of the same traits, so Mendel could be sure that if any changes he saw were result of the crosses he made during Cross-Pollination (white x purple). He called this Parental (P) generation The offspring of this 1st cross was called (F1 Generation) He then self-pollinated the F1 offspring and recorded data of the offspring of the 2nd generation, (F2 Generation) Certain drugs have become popular among teens and young adults at dance clubs and raves.

Analysis: The F1 generation always displayed one trait regardless of which was male or female (he later called this the dominant trait) The F1 generation must have within it the trait from the original parents - the white trait The F2 generation displayed the other hidden trait, 1/4 (25%) of the F2 generation had it (he later called this hidden trait the recessive trait) Each individual has two "factors" that determine what external appearance the offspring will have. (We now call these factors genes or alleles) Certain drugs have become popular among teens and young adults at dance clubs and raves.

What was Mendel’s Hypothesis from this research? He established 3 principles (Laws)” Law of Dominance and Recessive – If the two alleles (traits) differ, the dominant allele is expressed and the other trait (recessive) is masked or covered up by dominant trait Law of Segregation - the two factors (alleles) for each trait separate during gamete (egg and sperm) formation Principle of Independent Assortment - factors of a trait separate independently of one another during gamete formation; another way to look at this is, whether a flower is purple has nothing to do with the length of the plants stems - each trait is independently inherited Certain drugs have become popular among teens and young adults at dance clubs and raves.