Unit 5 - Chromosomal Basis of Inheritance - Episode 1 Flashcards
under transmission genetics
Mendelian Inheritance
What is the principle behind the transmission genetics?
- Blending hypothesis
- Particulate Hypothesis of Inheritance
traits of mother + traits of the father = yun yung traits mo
Blending hypothesis
It fails to explain the reappearance of traits after they’ve skipped generation
Blending hypothesis
this is the gene idea
main focus of mendelian inheritance
Particulate Hypothesis of Inheritance
the discrete heritable units
namamana or napapasa sa atin
Gene
may bagay or substance sa katawan natin na napapasa from generation to generation.
Hindi nawawala yung trait sa next generation since naipapasa or napapamana natin ito.
Particulate Hypothesis of Inheritance
It is a fertilization in which two gametes come from the same individual.
Nagfefertilize mag-isa.
Self-fertilization
other term for self-fertilization
selfing / pagsosolo
naturally self–fertilized; they have egg producing organ and sperm producing organ.
Pea Plants
In the case of pea plants:
_______ is the pollen producing organ. This pollen will now release sperm.
Stamen
In the case of pea plants:
________: the egg – bearing organ
Carpel
Facilitates fertilization between separate individuals
Magkahiwalay yung egg and sperm, nasa magkaibang specie.
Cross-fertilization
Other name for cross-fertilization
Cross-breeding
We remove the stamen so that walang magfefertilize doon sa egg and then kukuha ng pollen from other plants tapos yun ang ilalagay sa carpel.
cross-fertilization
Offspring of your parents that differ in only one genetic characteristics
Monohybrid
Offspring of your parents that differ in only two genetic characteristics
An organism heterozygous with two loci
Dihybrid
Genetic factors/fraction that helps determine your characteristics
Gene
Alternate forms of a gene
Allele
Set of alleles that an individual possesses
Genetic makeup
Genotype
Observable characteristics of an organism
Phenotype
Two types of Genotype
- Homozygous
- Heterozygous
alleles are the same (PP or pp)
Homozygous
alleles are different (Pp)
Heterozygous
_________ alleles determines the organism’s appearance
Dominant
______ allele has no noticeable effect on the appearance of an individual.
Recessive
If dominant allele is present, it will always be followed
(Law of Dominance)
A characteristic of an individual that is transmitted from generation to generation.
Trait/Character
A mating between two individuals, leading to fusion of gametes
Cross
The progeny of mating of individuals of the P generation
F1 generation (the first filial generation)
The progeny resulting from F1 generation individuals
F2 generation (the second filial generation)
The specific place on a chromosome where a gene is located
Locus (gene locus; plural loci)
Parental generation in breeding experiments
P generation
When a trait being studied remains unchanged from parent to offspring for many generations. Typically this means that there is homozygosity for the allele responsible for the trait
True-breeding
The cell produced by the fusion of male and female gametes
Zygote
Father of Genetics
Gregor Mendel
Gregor Mendel is an Australian Monk in _______
Brno (Czech Republic)
Mendel conducted breeding experiments form ____ to ____
1856 to 1863
Mendel presented his results publicly at meeting of the ____________ in 1865
Brno National Science Society
Mendel’s paper from these lectures was published in ____
1866
Mendel’s experiment was not recognized due to lack of evidences not until individual experiments were conducted by
Hugo De Vries,
Karl Franz Joseph Erich Correns,
Seysenegg (Erich von) Tschermak
previous generation is same sayo; pure blood
True-breeding
single characteristics passed on
Monohybrid cross
This mating, or crossing, of two true-breeding varieties is called
hybridization
The true – breeding parents are referred to as the
P generation or Parental generation
MONOHYBRID CROSS STEPS
- To cross different varieties of peas, remove the anthers (stamen) to prevent self-fertilization.
- Dust the stigma with pollen from a different plant
- The pollen (sperm) fertilizes the ova within the flower, which develop into seeds.
- The seed grows into plants.
discovered the Punnett square
Reginald C. Punnett
is a handy diagrammatic device for predicting the allele composition of offspring from a cross between individuals at known genetic makeup.
Punnett Square
BREAK TIME: MUSIC PLAYED DURING LECTURE:
- I Wish You Would by Taylor Swift
- Robbers by The 1975
- Anti-Romantic by Tomorrow x Together
(Degree of Dominance) masking of recessive traits by dominant traits. Common.
Complete Dominance
(Degree of Dominance) neither allele is completely dominant. A phenomenon where either of the traits cannot be distinguished from each other (blending of traits – white + red = pink). Not common.
Incomplete Dominance
two alleles affect the phenotype in separate, distinguishable ways. Both dominant and recessive alleles affect the phenotype. Example: ABO Blood Group
Codominance
first described the theory of dominance among blood groups.
Bernstein (1924)
An individual inherits one ABO gene from each parent and these two genes determine which ABO antigens are present in the RBC membrane.
Transmission Genetics in Blood Group
location of ABO genes. (palatandaan na ang ABO is codominant in expression.)
Chromosome 9
amorph; group O phenotype is an autosomal recessive trait. Two O must be present to become a blood type O.
O gene
Mendel’s First Law
Principle of Segregation
During gametes formation, two alleles segregate randomly with each gamete having equal probability of receiving either allele.
Law of Segragation
Law of segregation and ______________________ works hand in hand
It explains law of segregation
chromosome theory of heredity
states that genes are located on chromosomes
The chromosome theory of inheritance
Probability scale ranges from 0 to 1.
An event that is certain to occur has a probability of 1, while an event that is certain not to occur has a probability of 0
The probabilities of all possible outcomes for an event must add up to 1
Probability Laws
Each probability laws phenomenon is called
independent events
Used if the events are not mutually exclusive.
Probability of an event occurring in some specific combination is the product of their probabilities.
Both of the event will happen.
Multiplication Rule
They key indicator for applying the multiplication rule is the word
“and”
Probability that any one of two or more mutually exclusive events will occur is calculated by adding their individual probabilities.
Only one of the events will happen.
Addition Rule
The key indicator for applying the addition rule are the words
“either” and “or”
Appear in both sexes with equal frequency, and both sexes are capable of transmitting these traits to their offspring
Autosomal Dominant
Every person must have inherited the allele from at least one parent.
DO NOT SKIP GENERATION
Autosomal Dominant
Inherited disease in which blood cholesterol is greatly elevated due to the defect in cholesterol transport.
Familial hypercholesterolemia
an essential component of cell membranes and is used in the synthesis of bile salts and several hormones.
Cholesterol
Since cholesterol is a lipid (a nonpolar, uncharged comp.), it is not readily soluble in the blood (polar, charged solution). Cholesterol must therefore be transported throughout the body in small soluble particles called
lipoproteins.
consists of a core of lipid surrounded by a shell of charged phospholipids and proteins that dissolves easily in blood
Lipoproteins
One of the principle lipoproteins in the transport of cholesterol is
low-density lipoprotein
When an LDL molecule reaches a cell, it attaches to an__________, which then moves the LDL through the cell membrane into the cytoplasm, where it is broken down and its cholesterol is released for use by the cell.
LDL receptor
Familial hypercholesterolemia is due to a defect in the gene (located on _____________) that normally codes for the LDL receptor.
human chromosome 19
_________________ang familial hypercholesterolemia kaya walang kakapitan so sa blood lang yung cholesterol.
Lipids kakapit sa LDL receptor para maipasok ang cholesterol sa cell.
LDL receptor deficiency
Normally appear with equal frequency in both sexes
Appear only when a person inherits two alleles for the trait, one from each parent.
Autosomal Recessive
TRAIT APPEARS TO SKIP GENERATIONS
A recessive allele may be passed for a number of generations without the trait appearing in a pedigree.
Autosomal Recessive
Mating between closely related people is called
consanguinity
The disease results from the accumulation of a lipid called GM2 ganglioside because they lack hexosaminidase A
Tay – Sachs Disease
GM2 ganglioside is usually broken down by an enzyme called
hexosaminidase A
Excessive GM2 ganglioside accumulates in the brain, causing
swelling and ultimately neurological symptoms.
Accumulate chylomicrons
- Familial chylomicronemia syndrome (FCS)
Lipoprotein Lipase Deficiency (LPL)
Absence of HDL – transport cholesterol from tissues to liver
Mutation of ABCA1 gene in chromosome
Tangiers Disease
ABCA1 gene
ATP Binding Cassette A1 gene
Appear more frequently in males.
Since males need inherit only single copy of allele to display the trait
X-Linked Recessive
Male also inherit his X chromosome from his mother. Affected males are usually born to unaffected mothers who carry an allele for the trait.
they are not passed from father to son,
because a son inherits his father’s Y
chromosome, not his X.
X-linked Recessive
Rare X-linked recessive traits appear more often in males than in females and are not passed from father to son. Affected sons are usually born to unaffected mothers; thus X-linked recessive traits ____________________
tend to skip generations
Results from the absence of a protein necessary for blood to clot.
The complex process of blood clotting consists of a cascade of reactions that includes more than 13 different factors.
Hemophilia
results from abnormal or missing factor VIII, one of the proteins in the clotting cascade. The gene for factor VIII is located on the tip of the long arm of the X chromosome
Hemophilia A
Hemophilia A is an ______________________ disorder
X-linked recessive
People with ________________bleed excessively; even small cuts and bruises can be life threatening. Spontaneous bleeding occurs in joints such as elbows, knees, and ankles, which produces pain, swelling, and erosion of the bone.
Hemophilia A
Appear more in female
Inherit X chromosomes from both mother and father; so females can receive an X-linked trait from their parents.
traits do not skip generations
X-Linked Dominant
People with this trait have features that superficially resemble those produced by rickets: bone deformities, stiff spines and joints, bowed legs, and mild growth deficiencies
This disorder is resistant to treatment with vitamin D
Hypophosphatemia (Vitamin D resistant rickets)
results from the defective transport of phosphate, especially in cells of the kidneys.
Hypophosphatemia (Vitamin D resistant rickets)
People with this disorder excrete large amounts of phosphate in their urine, resulting in low levels of phosphate in the blood and reduced deposition of minerals in the bone.
Male with this disease are more severely
affected than females.
Hypophosphatemia (Vitamin D resistant rickets)
Only males are affected. Traits are passed from father to son.
Does not skip generations
Y-Linked Trait
