Upload
rosalind-carson
View
214
Download
0
Embed Size (px)
Citation preview
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