mrs. baxter and mrs. herndon 5th life science bill nye genetics video genetics

Mrs. Baxter and Mrs. Herndon

5th Life Science

Bill Nye Genetics Video

Genetics

1. Genetics is the study of genes, heredity, and genetic variation in living organisms. 

https://genetics of a four leaf clover

2. DNA (Deoxyribonucleic Acid) - carries the genetic information for a cell and is a set of instructions that tells the cell what to do or be.

3. Chromosome – a single long molecule of DNA (x shape).

https://brain pop DNA/

4. Gene – a part of the chromosome that contains DNA

Traits:

What are traits?

1. Traits are characteristics we

inherit from your parents.

2. The environment we grow up

and live in also helps define our

traits. For example: exposure to

chemicals or sunlight can change hair color

Genetic traits

5. Inherited trait – a characteristic passed from parents to their offspring. 6. Dominate trait – a strong trait that appears even if the organisms has only one factor. 7. Recessive trait – a trait that appears only if an organism has two factors. 8. Hidden trait – a trait that an organism carries, but is not expressed.

Dominant vs. Recessive Traits●9. Allele - one of a pair of genes that control a trait, such as blood type or colorblindness.

●Alleles are different “flavors of genes”●They will be either dominant or recessive traits

●There will always be 1 allele from the Mother and 1 allele from the Father

●a diagram called the Punnett Square●Punnett Square Video

More say of the outcome of that trait

No say unless there are 2 recessive alleles

What is Heredity?

10. Heredity - the passing on

of traits from parents to a child

We inherit traits from our parents

1. What traits have your inherited from your parents?

2. Why do brothers and sisters resemble each other?

DNA (“De-oxy-ribo-nucleic” Acid)Chemical code Master copy of instructions

for cell structure and function

Give us our traits like hair color, eye color, height, personality, & talents

Each gene makes proteins (building blocks for everything in your body)

DNA (“De-oxy-ribo-nucleic” Acid)Structure (what it looks

like) Three dimensional helix

Spiral staircase or

twisted ladder

Humans have 46 pairs

of chromosomes (or 23

pairs)

Half from one parent &

half from another parent

DNA Structure Cross pieces, “rungs” are

made of nitrogen base pairs

Same two bases always pair together:

adenine (A) & thymine (T)

cytosine (C) & guanine (G) The matching of the base

pairs, (A with T) and (C with G), provides a way for exact copies of DNA to be made called DNA replication.

DNA Mutation - Damaged chromosomes

- Mismatched base pairs

DNA Mutation - Mistakes in the DNA

- Example: albinism

DNA Discovery/History (1950-1960’s) - Rosalind Franklin 1st to

x-ray DNA

DNA X-rayRosalind Franklin

DNA Discovery/History (1950-1960’s) Maurice Wilkins gives Rosalind

Franklin’s x-rays to James Watson and Francis Crick

Crick and Watson make the 1st model of DNA

Rosalind Franklin dies of cancer

Wilkins, Watson, and Crick share a Nobel Prize for the DNA model

DNA Model

DNA Discovery/History (1950-1960’s)Maurice Wilkins

James Watson and Francis Crick

DNA Model Sketch