Biology Unit 5 Quiz 1 Study
chromosome
A "threadlike" molecule in the nucleus, composed of DNA. A chromosome possesses one allele for a given trait, therefore chromosomes occur in pairs. Each originates from the male and female gamete (parent).
which differ in only one trait
A monohybrid cross is made between plants:
pure-bred
A phenotype (trait) resulting from homozygous genes from the offspring of true breeding.
allele
Alternative forms of a gene for each variation of a trait of an organism. (R and r)
a pair of genes
Each trait characteristic of a plant is determined by:
F1 generation
First filial generation; the first generation from a given cross
Chromosomes
Genes are located on __________
false
Gregor Mendel was a respected, professional scientist who introduced the science of biology. t/f
remove the stamen!
In addition to covering each pea plant to prevent pollination from other pea plants in his garden, what did Mendel do to prevent self-pollination?
amino acids
In general, plant protein is low quality protein because they are short some of the _________ essential for human growth and development
one
Mendel found that for each of the seven pairs of traits, ______ of the characteristics present in the parent plants was apparently lost in the next generation.
seed shape, seed color, seed coat color, pod shape, pod color, flower position, plant height
Mendel studied 7 traits:
During gamete formation the pair of factors (genes) controlling a trait separated into single, individual gametes. Each gamete carried only one gene for the trait from each pair.
Mendel's first principle: the principle of segregation:
In explaining this principle he introduced the use of symbols such as Y and y to represent dominant and recessive traits, respectively. He suggested that each plant inherits two distinct hereditary factors for each trait, one from each parent. During pollination the plant passes one of the two factors in each reproductive cell (pollen grain or ovule).
Mendel's second principle: the principle of dominance and recessiveness:
According to this principle, the separation of genes on a given pair of chromosomes into gametes is completely independent of the distribution of any other chromosome pair. Note that this principle applies only when the two traits being studied are on different chromosome pairs since the chromosomes, and not the genes, assort independently.
Mendel's third principle: the principle of independent assortment:
stamen
Normally, pea plants self-pollinate; but to selectively crossbreed his plants, Mendel would remove the ________ and cover the flower with a bag to prevent chance pollination from other pea plants in the garden.
F2 generation
Second filial generation; offspring of the F1 generation.
dominant trait
Since traits of P1 plants did not blend in producing the F1, plants, Mendel called the trait that was apparent in the F1 generation the __________
self-fertilized F1 plants
The F2 plants were grown from seeds collected from ________________.
incomplete dominance
The blending of two traits in a heterozygous individual.
dominant
The characteristic which resulted from a monohybrid cross is the ________ trait.
a paired combination of genes
The genotype represents:
one chromosome pair
The multiple combinations of gametes indicates that the traits being studied appear on different pairs of chromosomes and that, when the pairs of chromosomes divide during meiosis (gamete production), ___________ exerts no influence on any other chromosome pair
hybrid
The plants that grew are the F1 or _______
segregation
The reduction of a gene pair to an allele during the formation of a gamete is called the principle of _________
F1 or hybrid
The seeds collected from the first generation monohybrids are called:
pistil
When crossing a pair of similar plants that differed only in a single trait, Mendel dusted pollen from one strain on to the ________ of the opposite trait flower
genotype
When the genes of an organism are represented by pairs of symbols for a trait being studied, this pairing indicates the organism's ________.
multiple alleles
Where more than two alternatives for a gene exist
Genesis 1:24 and Genesis 1:12
Which scriptures describe a biologic law of reproduction for which no exception has ever been documented? (Verses are from NKJV.)
Gregor Mendel
Who was the Father of the Science of Genetics?
to control the crossing of traits
Why did Mendel prevent his plants from self-pollinating?
recessive
a gene or trait which is masked when a dominant allele is present
trait
a genetic characteristic of the individual
DNA
a giant molecule consisting of the sugar deoxyribose, phosphates and nitrogen bases; contains the coded genetic information
Punnett Square
a grid system used to predict possible combinations of genes due to random fertilization
gene
a portion of DNA which codes a specific hereditary trait
meiosis
a type of cell division used to produce gametes and there is a reduction in the chromosome number from the diploid to the haploid number
hybrid
an offspring from a cross between parents which has different phenotypes for a specific trait
dihybrid cross
breeding of individuals which have genes for two different characteristics
tetrad
during metaphase I the two pairs of chromatids of the homologous pair of chromosomes comes together, crossing-over can occur at this time
dominant
in a pair of genes, one may prevent the allele from being expressed
The chance that a given event will occur usually expressed between the number 0 (will not occur) and 1 (the event will occur).
probability
heterozygous
refers to a pair of genes for a specific trait in an organism which are different
homozygous
refers to a pair of genes in an organism which are identical in the way they influence a trait
gamete
reproductive cell produced by the male or female parent, which contains the haploid number of chromosomes
test cross
the breeding of an individual which possesses the dominant trait to a homozygous recessive for that trait
monohybrid cross
the breeding of two organisms which differ in a single trait
genotype
the genes present in an organism
self-fertilization
the organism, which possesses both male and female gametes, brings the two genetically identical gametes together to produce offspring
phenotype
the outward appearance of the organism which is the product of gene action
P1 generation
the parental generation for a given cross
true-breeding
the process of crossing two organisms, both having homozygous genes for the same trait.
pollination
transfer of pollen, male gamete, in plants to the stigma which contains the female gamete
deviation
variation from the predicted values