Download 7-2.5 Genetic Information is Passed from Parent to Offspring

Genetic Information
is Passed from
Parent to Offspring
7-2.5 Summarize how genetic information is passed from
parent to offspring by using the terms genes, chromosomes,
inherited traits, genotype, phenotype, dominant traits, and
recessive traits.
Bell Ringer
Wolf Family
Analyze the wolf family on
pages 98-99. What
similarities can you see
between the mother wolf
and her offspring?
Bell Ringer 11-11-14
Strong Genes
Has anyone ever told
you that your family
has strong genes?
What did they mean?
Homework for the week-Write
in your agenda now!
Standardized Test
Practice-”The
Euglena Puzzle” pg.
37 (1-7); Due Friday,
11-14
Essential Question
How do your genes
related to the way
that you look?
Objective
Analyze terms
related to genes
and heredity.
Standard
• Standard 7-2.5 Summarize how
genetic information is passed
from parent to offspring by using
the terms genes, chromosomes,
inherited traits, genotype,
phenotype, dominant traits, and
recessive traits.
Genes and Heredity
Introduction
• Use your various references to define the following 10 terms
using any vocabulary strategy from pages R50-R51:
1. Trait
2. Heredity
3. DNA
4. Chromosomes
5. Gene
6. Allele
7. Genotype
8. Phenotype
9. Dominant Trait
10. Recessive Trait
1. Traits
• Offspring may have the same physical
characteristics, or traits, as their parents because
genetic information (DNA) is passed from parent
to offspring during sexual reproduction.
• Each sex cell (egg or sperm) of the parent
organism (plant or animal) contains one-half of
the genetic material needed to create a new
organism.
2. Heredity
• Heredity is the passing of traits from
one generation to another, or
inheritance.
3. Chromosomes
• Chromosomes=structures found in the
nucleus of a cell that contains the genetic
information (DNA). Chromosomes are
located in the nucleus of the cells.
4. Genes
• Genes= A segment of DNA found on a
chromosome that determines the inheritance of
a particular trait.
• Genes are responsible for the inherited
characteristics that distinguish one individual
from another.
5. Allele
• Genes for a specific trait generally come in pairs.
• One gene from the pair is called an allele.
6. Genes Are Expressed in
Different Forms
• Genes may be expressed in two different forms.
• Genotype—the set of genes carried by the organism.
• Phenotype—the physical expression of the genes.
Genotype Verses Phenotype
Genotype –Letters
that tell the look
Phenotype –Physical
Looks
TT
TALL
Tt
TALL
tt
short
7. Inherited Traits
• Characteristics that are passed from parent to offspring.
Examples of inherited traits may be eye color, eye shape, hair
type, or face shape.
• Some inherited traits are dominant and some are recessive.
8. What do these 2 girls have in
common?
9. Dominant Trait
• Dominant trait—A trait that will always be expressed in the
phenotype. Alleles for dominant traits are represented by
capital letters.
•Dimples are a dominant
trait.
•DD, Dd
10. Dominant Traits
Trait
Dominant Trait
Hair Type
Curly or Wavy
Hair Color
Dark
Dimples
Having Dimples
Earlobes
Free
11. Recessive Traits
• Recessive trait—A trait that will
only be expressed in the
phenotype if two recessive alleles
are present. In the presence of a
dominant trait, the recessive trait
will not be expressed. Alleles for
recessive traits are represented by
lowercase letters.
12. Recessive Traits
Traits
Recessive Traits
Hair Type
Straight
Hair Color
Light
Dimples
No dimples
Earlobes
Attached
Analyze Your Peers
•
•
•
•
Select a peer from your station.
Interview your peer about his/her traits.
Draw and color the peer to the best of your ability.
Complete the following data table based on your analysis:
Name of Your
Peer___________
Hair Type
Hair Color
Dimples
Earlobes
Physical Traits
Where did the
trait come from?
Is the trait a
dominant or
recessive trait?
Quick Review – 2 Corners
Trait
Hair Type
Dominant
Curly or Wavy
Recessive
Straight
Hair Color
Dark
Light
Dimples
Having Dimples No dimples
Earlobes
Free
Attached
Genes and Heredity
Review-7-2.5
1. What are 2 forms of the same gene
called?
a. Phenotypes
b. Genotypes
c. Dominant Traits
d. Alleles
Genes and Heredity
Review-7-2.5
2. In humans, having dimples is a dominant
trait. You meet a person and notice that she
does not have dimples. What can you
conclude about this person?
A. She has inherited 2 recessive alleles for the
dimple trait.
B. She has inherited 1 recessive allele for the
dimple trait.
C. She had inherited 2 dominant alleles for the
dimple trait.
D. She had inherited 1 dominant allele for the
dimple trait.
Genes and Heredity
Review-7-2.5
3. Where are the chromosomes of an
organism located?
a. On the genes
b. On the alleles
c. In the nuclei of the cells
d. In the DNA molecule
13. Relevant Questions
13. Dominant and Recessive
Traits
14. Traits Data Table
Trait
Phenotype
1. Hair color
brown, black, or red hair
LL or Ll
blond hair
ll
naturally curly
TT or Tt
naturally straight
tt
can curl tongue
CC or Cc
cannot curl tongue
cc
hair present, middle digit of finger
MM or Mm
hair absent, middle digit of finger
mm
eyes not blue
EE or Ee
blue eyes
ee
peak in center of hairline
WW or Ww
no peak in center of hairline
ww
little finger curves toward others
BB or Bb
2. Hair type
3. Tongue curling
4. Mid-digital hair
5. Pigmented iris
6. Widow's peak
7. Bent finger
little finger straight
X
Genotype
bb
15. Relevant Questions