Download Heredity Basics

Daily Science
1. Christmas
2. In the movie, “It’s a Wonderful
Life,” what did Clarence get for
accomplishing his mission?
3. What were Frosty the
Snowman’s last words?
Standard
S7L3
UNDERSTAND THE IMPORTANCE OF HOW
BIOLOIGICAL TRAITS ARE PASSED ON FROM
GENERATION TO GENERATION
Learning Target
I can understand
terminology used in
genetics.
Heredity Basics
Heredity Basic Notes
1. Heredity is the passing of traits
from parent to offspring.
The study of how these traits are
inherited is genetics.
What is genetics?
2. Genes are found on chromosomes and
control the traits that show up in an
organism. The different forms a gene may
have for a trait is an allele.
(During MEIOSIS, a pair of chromosomes
separate and the alleles move into
separate gametes. Each gamete now
contains 1 allele for each trait.)
Mendel-the father of Genetics
3. Mendel was the first to use
mathematics of probability to explain
heredity and to trace one trait for
several generations.
Hybrid & Purebred
4. Hybrid organisms receive different genetic
information for a trait from each parent.
5. An organism that always produces the same
traits generation after generation is called a
purebred. PUREBRED organisms receive the
same or identical genetic information for a
trait from each parent.
Dominant and Recessive
6. The dominant allele covers up or
dominates the other allele.
7. The recessive allele seems to be
covered up or “disappears.”
Probability
8. Probability helps one predict
the chance that something will
happen.
Punnett Squares:
9. A Punnett square can help predict
what an offspring will look like.
10.Upper case letters stand for
dominant alleles. Lower case
letters stand for recessive alleles.
Genotype and Phenotype
11. The genotype is the genetic
makeup of an organism. The
phenotype is the way an organism
looks or behaves as a result of the
genotype. (The phenotype is the
expression of the genotype)
Homozygous & Heterozygous
12. An organism with two alleles that are the
same is said to be homozygous.
Would this organism be hybrid or purebred for
this trait? Purebred
An organism with two alleles for one trait that
are different is said to be heterozygous.
Would this organism be purebred or hybrid for
this trait? hybrid
Explain Figure 2, Page 127
7. Alleles separate into gametes during meiosis.
In this way, each zygote receives TWO alleles.
One allele is from the mother and one allele is
from the father.
Math Skills
1. 75% were yellow
2. Genotype yy = 25%
Principles of Heredity, Page 132
1. Traits are controlled by alleles on
chromosomes.
2. An alleles effect is dominant or recessive.
3. When a pair of chromosomes separates
during meiosis, the different alleles for a trait
move into separate gametes.
Heterozygous or Homozygous
Which gene is heterozygous? Aa
Which gene is homozygous? BB
Daily Science - Mendel and the
Scientific Method
Explain how Mendel used the Scientific Method
during his experiments.
Explain how Mendel’s experiments
illustrate the scientific method.
1.
2.
3.
4.
He made observations.
He asked questions.
He formed a hypothesis.
He performed carefully controlled
experiments and experimented on only
ONE trait at a time.
5. He collected and analyzed data.
6. He then shared his findings/results.