INTRO TO GENETICS 4.1-4.2.2

By Chrissy, Matthew, Louise, and Savannah

Pre-assessment 1. Define gene and allele.2.  What does homologous chromosome

mean?3.  What is one thing eukaryote

chromosomes are made of?4.  Define gene mutation.5.  What is sickle cell anemia?6. What is the purpose of meiosis?

4.1.1 Eukaryote chromosomes are made of

DNA and protein.This is because chromosomes in a

Eukaryote are found in a nucleus.Chromosomes contain DNA and protein.

4.1.2 Genes Definition- a unit of heredity in a living

organismLocated in DNAControls a specific characteristic (example-

eye color)Occupies a location on the chromosomes

called a locus

4.1.2 Allele Definition- a specific form of a gene

Differs from other alleles by one or a few bases only

Occupies the same gene locus as other alleles of the gene

4.1.2 Genome Definition- the total genetic material of

an organismCell or organismHuman genome project

4.2.1 Gene Mutation Definition- a permanent change in the

genetic makeup of an organismCan affect only one nucleotide or multiplesOccur in two ways

○ Inherited from a parent○ Acquired during a person’s lifetime

Ex. Manx cat

4.1.4 Sickle Cell Anemia Sickle Cell Anemia is a disease passed

down through heredity that is caused by a base substitution mutation in DNAMutation occurs during transcription and

translationGlutamic acid is replaced by ValineGAG mutates to GTG causing sickly, sickle

shaped red blood cells

4.2.1 Meiosis Meiosis is a reduction division of a

diploid nucleus to form haploid nucleiThe product is 4 identical sex cellsHaploid: Cells used in sexual reproduction.

Contain 1 set of chromosomes.Diploid: Cells used as skin, blood, or muscle

cells. Contain 2 sets of chromosomes

4.2.2 Homologous Chromosomes Definition- 2 chromosomes, one from

each parent, that look the sameSame sizeSame banding pattern in a karyotype Carry the same genes but not necessarily

allelles Ex. 2 chromosomes for eye color that look

the same, but one may be brown and the other may be blue

4.2.2 (cont.)Chromosomes will pair up and split during

meiosis

Activity Each person will receive a balloon and a

slip of paper with a question on it Take a sharpie and write your question

on your balloon When we begin, pass the balloons

around and choose a person to answer a question

If you answer correctly you may pop your balloon. If not we will continue to pass it.

Works Cited Free Homework Help Videos from

Brightstorm - Math, Science, Test Prep - Brightstorm. Web. 10 Feb. 2012. <http://www.brightstorm.com/>.