7th science sub plan 1

​ Summarize why some traits cannot be inherited and how inherited traits are passed from one

generation to the next by genes.

• Explain why sexual reproduction produces more genetic variation than asexual reproduction.

• Identify basic patterns of inheritance.

• Use Punnett squares and pedigree diagrams to predict the probabilities of certain genotypes and phenotypes.

• Describe the relationships among genes, chromosomes, and DNA and their functions in cells and living things.

• Describe the structure of DNA and its role in the building and functioning of organisms.

• Construct an explanation for how changes in DNA can affect organisms.

• ​

• ​These are from lessons 5.1 and 5.2 , but don't worry if you are not there yet

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​on youtube, search for

​

​Science Rap Academy DNA

​there are 2 types of reproduction

​

​sexual reproduction

​ takes 2 parents

​ the offspring (kids)

​ are each different

​

​asexual reproduction

​ only takes a mom

​ the offspring is

an exact copy of mom

​DNA is made up of A, T, C, and G

​

​sometimes, typos are made

​ these are called mutations

​

​one type is called a

substitution mutation

​substitute means replace one with another

​

​in the pic, notice the C changed to a T. nothing else changed

​

​Look at the top DNA chain

​

​DNA is read three letters

​ at a time

​

​When a mutation type occurs

​ and inserts an extra nucleotide letter

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​all of the 3-letter words after that mutation are messed up (no more cats )

​This time, a letter is deleted

​ and all the words are shifted

​

​this shifting is called a

​ Frameshift mutation

​it is a type of mutation that

​occurs when everything

afterwards is messed up

​

​insertion and deletion are both types of frameshift mutations

​

mutations can be caused by

​ random typos (copying mistakes)

​ environment (mutagens)

​ also called carcinogens

​

​they can be

​ helpful

​ harmful

​ deadly (fatal)

​now, search on youtube for

​

​

​

​science rap academy phenotype

​

​listen and take notes

​Gregor Mendel was a monk that grew peas and figured out some classic genetic stuff.

​

He controlled who was the mom and the dad of these plants to do experiments.​

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​for example,

​The height of the plants and the color of the peas did not affect each other.

​

​

​If you have 2 different forms of a gene,

​ they have to decide which one will show

​

​in most cases, there is a

​ Dominant gene that we represent with a capital letter

​ and a

​ recessive gene that we represent with an lower case letter

​

​homo-

​ means the same

​

​hetero-

​ means different

​

​if both are dominant

​or both are recessive,

​ it is homozygous

​To start a Punnett square,

​ draw a 4-paned window

​ put the genotype of the dad at the top

​ and the genotype of mom on the side

​ one letter per pane

​

​Each of the 4 panes represents a 25% chance the offspring will have the resulting genes

​each of the top letters goes down

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​each of the left letters goes across

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​you should end up with two letters in each box

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​on youtube, watch

​Mahalo Punnett

​Punnett squares work with dominant

and recessive genes of traits controlled

with one gene

​

​incomplete dominance is where

red and white really would make pink, or show the average trait

​

codominant is where both traits would show, such as a flower having red and white stripes

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​then, there are other traits that are controlled by more than one gene!

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a family tree that shows a genetic trait

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​females are circles

​males are squares

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​light colored shapes do not have that trait

​dark colored shapes do have the trait