Download LS DNA, Heredity and Genetics Booklet PP

Why you resemble your parents and grandparents?
How do organisms transmit genetic information to the
next generation?
DNA, Genetics and Heredity
 PAGE 1- WHAT KIND OF CHARACTERISTICS CAN BE INHERITED FROM PARENTS?
 PAGE 2- WHAT ARE CHROMOSOMES, GENES, AND DNA?
 PAGE 3- WHAT DOES DNA DO?
 PAGE 4- WHAT IS THE SHAPE OF DNA?
 PAGE 5- WHAT IS DNA MADE OF?
 PAGE 6- MATCH DNA CODE
 PAGE 7- HOW DOES DNA PASS ON?
 PAGE 8- HOW DOES DNA REPLICATE?
 PAGE 9- WHY IS DNA REPLICATION NECESSARY?
 PAGE 10- THE ORGANISM NOW HAS CODED INFO FROM BOTH PARENTS, NOW WHAT?
 PAGE 11-WHAT IS A DOMINANT TRAIT? What is a recessive trait?
 PAGE 12- WHAT IS A PUNNETT SQUARE?
 PAGE 13- WHAT IS A GENOTYPE?
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WHAT IS A PHENOTYPE?
WHAT IS HETEROZYGOUS?
WHAT IS HOMOZYGOUS?
PAGE 14- WHAT SCIENTISTS CONTRIBUTE TO OUR KNOWLEDGE OF GENETICS
PAGE 15- WHAT IS GENETIC ENGINEERING?
PAGE 1
 WHAT KIND OF CHARACTERISTICS CAN BE
INHERITED FROM PARENTS?
 PHYSICAL TRAITS OR CHARACTERISTICS CAN BE
INHERITED THROUGH GENES.
 CHARACTERISTICS THAT ARE AQUIRED DURING
LIFE SUCH AS INJURIES OR PRACTICED SKILLS
CANNOT BE INHERITED.
PAGE 2
WHAT ARE CHROMOSOMES, GENES, AND DNA?
 Chromosomes are long strands of tightly wound DNA
found in the nucleus of cells.
 Genes are sections of chromosomes that carry
information for a specific physical trait (height or eye
color).
 DNA is the molecule that makes up genes
(deoxyribonucleic acid).
PAGE 3
WHAT DOES DNA DO?
 DNA contains coded instructions that store and pass
on genetic information from one generation to the
next.
PAGE 4
WHAT IS THE SHAPE OF DNA?
 DNA is a double-helix
 -shaped like a twisted ladder
PAGE 5
WHAT IS DNA MADE OF?
 The sides of the ladder are made of sugar and
phosphate and the rungs/steps of the ladder are
nitrogen bases.
PAGE 6
MATCH DNA CODE
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These bases are:
Guanine (G)
Cytosine (C)
Adenine (A)
Thymine (T)
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G always matches C
C always matches G
A always matches T
T always matches A
PAGE 7
HOW DOES DNA PASS ON?
 DNA must replicate before the cell divides (mitosis).
 During meiosis, DNA replicates a second time.
 When egg and sperm cells unite (fertilization), the
new organism(s) gets ½ of its DNA from the mother
and the other ½ from the father.
PAGE 8
HOW DOES DNA REPLICATE?
 DNA untwists and unzips down the middle and then
matches the codes down each side of the ladder.
 2 new ladders form.
PAGE 9
WHY IS DNA REPLICATION NECESSARY?
 The coded instructions tell the cell and the organism
what to do to carry on life functions.
PAGE 10
THE ORGANISM NOW HAS CODED INFO FROM
BOTH PARENTS, NOW WHAT?
 Each parent contributes one form, or allele, for each
physical trait (Ex. Brown eyes or blue eyes)
 One of these may dominate over the other.
PAGE 11
WHAT IS A DOMINANT TRAIT?
 The trait that you see or shows up.
 That trait that you do not see or doesn’t show up but is
still there in the genes hidden in the code.
PAGE 12
WHAT IS A PUNNETT SQUARE?
A tool for predicting the outcome of crossing/ mating 2
organisms for a single trait.
Purebred= 2 matching alleles (BB and ++)
Hybrid =2 unmatched alleles:
one is dominant and the other is recessive
BB=Brown eyes
Bb- Brown eyes
bb= Blue eyes
PAGE 13
WHAT IS A GENOTYPE?
WHAT IS A PHENOTYPE?
WHAT IS HETEROZYGOUS?
WHAT IS HOMOZYGOUS?
What is a GENOTYPE?
What the gene says (BB, Bb, bb)
What is a Phenotype?
What the organism looks like (brown hair, blue eyes)
What is heterozygous?
Organism with 2 different alleles for a trait (T+)= hybrid
What is homozygous?
Organism with 2 alleles that are the same for a trait (TT, ++)= purebred
PAGE 14
WHAT SCIENTISTS CONTRIBUTE TO OUR
KNOWLEDGE OF GENETICS
Scientist
Year
Contribution
Gregor Mendel
1856
Used peas to see how
traits are passed
Rosemary Franklin
1952
Used X-Rays to see DNA
is 2 chains in a spiral;
Watson and Crick
1953
Made model of DNA =
double helix
PAGE 15
WHAT IS GENETIC ENGINEERING?
 Methods used to change the arrangement of a gene’s
DNA to improve the organisms activities.