Chapter 3 Flashcards
Spermism
Fathers contribute essential characteristics while mothers only deliver the child (Pythagoras)
character
heritable feature that varies among individuals of a population
trait
a variant of a character found within a population
allele
alternative version of a gene
genotype
genetic makeup of an organism
phenotype
expressed traits of an organism
Mendel’s manipulation
he removed the stamen from the developing flower buds before they produce pollen
cross fertilization
pollen was taken from another flower and dusted in on the pistil of another
P generation
true breeding parental plants
F1 generation
progeny of P generation mating
Characteristics that were controlled by Mendel
- seed coat color/ flower color
- seed color
- seed shape
(7 total)
Monohybrid Cross
Cross between true breeding strains (Mendel Used Peas)
T/F Reciprocal crosses can result in same outcome.
True
Mendel Hypothesis 1
Alternative versions of genes (alleles) account for variation in inherited characters
Mendel Hypothesis 2
for each character an organism inherits two alleles (one from each parent)
Homozygous
two identical alleles
Heterozygous
two different alleles
Hypothesis 3
if two alleles of an inherited pair differ, then the dominant allele determines the organism’s phenotype.
Mendel’s First Law- Principle of Segregation
members of a gene pair segregate from each other during the formation of gametes in meiosis
Albinism
results from inheritance of recessive alleles
Product rule (and)
probability of two independent events occurring simultaneously is a product of each individual probability.
Sum Rule (or)
combine probability of two events that are mutually exclusive is the sum of the individual probabilities
Test cross
helps to identify the genotype of an organism with a dominant trait by examining its phenotype
Mendel’s second law- Law of independent assortment
alleles of different genes separate independently of each other during gamete formation
Chi-Squared test
compares expected data against collected data
Goodness of fit test
measures how well the observed data fits the expected data
Null Hypothesis
Hypothesis that there is no real difference between observed data and predicted data
reject null hypothesis
something external/ environmental influenced the data
Fail to reject Null
No real difference between observed data and predicted data
Degrees of freedom
n-1 (n= number of variables)
Autosomal recessive
only appears with homozygous recessive
autosomal dominant
appears with homozygous dominant and heterozygous dominant
X-linked recessive
appears in female-homozygous recessive and males with one copy of recessive allele
X-linked Dominant
appears in female homozygous/ heterozygous dominant. Males with one copy of dominant trait
Y-linked
only males are affected, thought of as if copy/trait is present or not
Achondroplasia (dwarfism)
Autosomal heterozygous dominant (Aa)
SRY Gene
Testis-determining factor (karyotype XXY)
Hemizygous
only have one allele copy
Hemophilia (clotting gene mutation)
X-linked Homozygous recessive (XhXh, XhY)
Viral Vector
modified virus that delivers gene to nucleus (nontoxic)
X-linked Dominant trait
same rules as X-recessive but heterozygous females express trait
Examples of X-linked Dominant diseases
- Vitamin D resistant rickets
- Fragile X syndrome
Examples of X-linked recessive diseases
- Hemophilia
- red-green colorblindness
Y-linked traits
-transfers father to sons only
- gene in nonhomologous portion of the Y chromosome
What two genotypes are crossed in a test cross?
Phenotypically dominant and phenotypically recessive
