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