View
214
Download
0
Category
Tags:
Preview:
Citation preview
Intro to GeneticsMr. Mah
Living Environment
Test Scores
• High: 95% Paige• Wilka 89%
• Elizabeth 87%
• Block 1 Average: 42%
• Block 4 Average: 40%
• Block 5 Average: 53%
Think for a second about the most crazy thing you have ever
seen…
when something like THIS could be possible…
Imagine in the future…
The future is now…
How did the scientists do
it?
INTRO TO GENETICS
GENETICS:the study of how traits are passed
from one generation to the next
TRAIT:a characteristic
Examples:Plant size, seed color, pod
shape
GENE:the factors that control traits
(found on chromosomes)
*can be passed down from one generation to another
CHROMOSOME:tightly coiled strands of DNA stored in the
NUCLEUS
* genes = segments of chromosomes
ALLELES:different forms
of a gene
GENESEach feature of the pea plants is controlled by a
gene. It may have a gene that controls its color, another for size and another for shape.
Above you see chromosomes. The circled area is a gene on chromosome #22. The absence of this gene causes velo-cardio-facial syndrome (VCFS)
which may cause ADD and mental illness
ALLELESEach gene comes in different forms called alleles,
so the gene that controls flower color may come in two alleles: purple and white.
GREGOR MENDEL• The “father” of genetics• Lived from 1822-1884• Austrian Monk• Published his work in
1866, but no one took him seriously until 1900.
• Studied Pea Plants!
MENDEL’S EXPERIMENTS
Mendel experimented with 7 different characteristics
How can we determine what the offspring are
going to be?
DOMINANT traits:allele that is always
expressed (TT or Tt = tall)
RECESSIVE traitsallele that is expressed
only when homozygous(tt = short)
HOMOZYGOUS organism with two identical alleles for
the same trait(TT or tt)
HETEROZYGOUS organism with two different alleles for
the same trait(Tt)
GENOTYPEthe genetic makeup
(TT, TtHh)*depends on the genes you
inherit
PHENOTYPEphysical
characteristics(Tall, Brown)
*depends on genes BUT can be affected by environmental factors
A child has brown hair and brown eyes. His father has brown hair and blue eyes. His mother has red hair and brown eyes. The best explanation for the child having brown hair and brown eyes is that
(A) A gene mutation occurred that resulted in brown hair and brown eyes
(B) Gene expression must change in each generation so evolution can occur
(C) The child received genetic information from each parent
(D) Cells from his mother’s eyes were present in the fertilized egg
A child has brown hair and brown eyes. His father has brown hair and blue eyes. His mother has red hair and brown eyes. The best explanation for the child having brown hair and brown eyes is that
(A) A gene mutation occurred that resulted in brown hair and brown eyes
(B) Gene expression must change in each generation so evolution can occur
(C) The child received genetic information from each parent (D) Cells from his mother’s eyes were present in the fertilized egg
In a particular variety of corn, the kernels turn red when exposed to sunlight. In the absence of sunlight, the kernels remain yellow. Based on this information, it can be concluded that the color of these corn kernels is due to
(A) A different type of DNA that is produced when sunlight is present
(B) A different species of corn that is produced in sunlight
(C) The effect of sunlight on the number of chromosomes inherited
(D)The effect of environment on gene expression
In a particular variety of corn, the kernels turn red when exposed to sunlight. In the absence of sunlight, the kernels remain yellow. Based on this information, it can be concluded that the color of these corn kernels is due to
(A) A different type of DNA that is produced when sunlight is present
(B) A different species of corn that is produced in sunlight
(C) The effect of sunlight on the number of chromosomes inherited
(D)The effect of environment on gene expression
Recommended