Biology - Chp. 10

The haploid cells of humans are called

gametes

A(n) ______ is a portion of DNA that encodes a protein.

gene

The genetic makeup of an individual is called the

genotype

A cell with one set of chromosomes is a(n) ______ cell.

haploid

A(n) ______ individual has 2 different alleles for a given gene.

heterozygous

If parents contribute different versions of a gene, then the offspring are ______ for that gene.

heterozygous

In Mendel's experiments, the hybrid plants had what genotype?

heterozygous

Two chromosomes that look alike and have the same sequence of genes in the same positions are a(n) ______ pair.

homologous

A ______ individual has two identical alleles for a gene.

homozygous

IF both parents contribute identical versions of a gene, then the offspring are ______ for that gene.

homozygous

Select all of the possible genotypes for the true-breeding plants in Mendel's experiments.

homozygous dominant homozygous recessive

A ______ organism produces mixed offspring: some that are identical to the parent plant and some that are different.

hybrid

Homologous chromosomes contain the same genes but may contain different alleles at a particular site, called a gene

locus

Cell division that results in the production of gametes is called

meiosis

In a population of fruit flies, a mutation arose that created white eyes; the white-eyed fruit flies have the ______ allele.

mutant

The variant that arises when a gene undergoes a genetic change is the ______ allele, genotype, or phenotype.

mutant

In a genetic cross, what does the P generation represent?

parental generation

The trait encoded by a(n) ______ allele will ONLY be exhibited when another allele does not mask it.

recessive

What type of trait in Mendel's studies could vanish in one generation and reappear in the next generation?

recessive

When pollen from the male parts of a flower becomes applied to the female part of the same flower, the process is called

self-fertilization.

One of the reasons that Mendel was able to discover the basic principles of genetics using pea plants is because pea plants ______.

self-fertilize and cross-fertilize

In the human genome, the X and Y chromosomes are called the

sex chromosomes

A ______ organism always produces offspring that are identical to the parent when self-fertilized.

true-breeding

If a gene exists in 10 different alleles in a population, how many alleles can be expressed in one diploid cell?

two

The symbol for a dominant allele is a(n) ______ letter, whereas the symbol for a recessive allele is a(n) ______ letter.

uppercase; lowercase

In a population of fruit flies, most flies have two antennae; based on this information, the phenotype of two antennae is definitely a ______ phenotype.

wild-type

The most common allele of a gene in a population of fruit flies is called the ______ allele.

wild-type

Rank the hereditary components from smallest at the top to largest at the bottom.

1. Nucleotide 2. Gene 3. Chromosome 4. Gamete

Mendel mated true-breeding pea plants that had yellow seeds (YY) with true-breeding pea plants that had green seeds (yy). In the F1 generation, ______% of the plants had yellow seeds, and ______% of the plants had green seeds.

100; 0

A diploid cell has ______ alleles for each gene, one on each homologous chromosome

2

A diploid cell has ______ alleles for each gene, one on each homologous chromosome.

2

Alternative forms of a gene are called

Blank 1: alleles, Alelles, allele, or alelle

Of the 23 pairs of human chromosomes, the 22 pairs of chromosomes that are the same in both sexes and are not sex chromosomes are called the .

Blank 1: autosomes

A cell with two complete sets of chromosomes is a cell.

Blank 1: diploid or diploid cell

A(n) allele always exerts its effects when present.

Blank 1: dominant

In humans, sex is determined by the sex chromosomes X and Y. If a human contains two X chromosomes, then its biological sex is typically ; but if a human contains an X chromosome and a Y chromosome, then its biological sex is typically .

Blank 1: female, girl, or woman Blank 2: male, boy, or man

The union of gametes to form a zygote occurs during a process called

Blank 1: fertilization or sexual reproduction

An individual's allele combination for a particular gene is called the

Blank 1: genotype

Gametes, or sex cells, are , meaning they contain only one set of chromosomes.

Blank 1: haploid, haploid cells, or haploid cell

The physical location of a gene on a chromosome is called the gene's .

Blank 1: locus or loci

A cell division process called shuffles the genetic information contained in chromosomes and produces cells called gametes. Gametes are cells because they only have one copy of each chromosome. unites sperm and egg to form a zygote, which has two copies of each chromosome and is therefore a(n)

Blank 1: meiosis Blank 2: haploid or sex Blank 3: Fertilization or fertilization Blank 4: diploid

A cell division process called shuffles the genetic information contained in chromosomes and produces cells called gametes. Gametes are cells because they only have one copy of each chromosome. unites sperm and egg to form a zygote, which has two copies of each chromosome and is therefore a(n) cell.

Blank 1: meiosis Blank 2: haploid or sex Blank 3: Fertilization or fertilization Blank 4: diploid

An individual's is its observable characteristics for a particular trait.

Blank 1: phenotype

If the genotype for a trait is Tt, the t allele is called the ______, allele, whose effect is masked by the other allele.

Blank 1: recessive

In plants, the production of seeds by the union of gametes from the same plant is called -fertilization, whereas production of seeds by the union of gametes from different plants is called -fertilization.

Blank 1: self, self-pollination, self-fertilization, or inbreeding Blank 2: cross, cross-pollination, cross-fertilization, or outcrossing

The first filial generation in a genetic cross is written as the ______ generation.

F1

The offspring of the first set of individuals mated in a particular cross is the

F1 generation

The second filial generation in a genetic cross is written as the ______ generation.

F2

Mendel chose traits whose phenotype was affected by the environment and only visible when viewed with a microscope.

False

What is a sequence of DNA nucleotides that holds the instructions to make a protein?

Gene

Who discovered the basic principles of inheritance using traits of pea plants?

Gregor Mendel

______ is the cell division process that occurs in diploid germ cells and gives rise to haploid cells.

Meiosis

______ formulated key principles of genetics before DNA, genes, and chromosomes were discovered.

Mendel

What is the first set of individuals mated in a particular cross?

P generation

What are the observable characteristics of an individual's genes?

Phenotype

Select all of the following that are true about dominance and recessiveness.

Recessive alleles typically encode nonfunctional proteins. A dominant allele may encode enough normal protein to mask the presence of the recessive allele. A dominant allele may cause a disease, such that the dominant allele is very rare.

Select all of the following that are true about genotype or phenotype.

Some phenotypes can be affected by the environment. Phenotype may not be readily visible.

Select all of the reasons why pea plants were a good choice for Mendel to use in his heredity experiments.

They develop quickly. They can be cross-fertilized or self-fertilized. They have traits that appear in two distinguishable forms.

A dominant allele can be rare, and a recessive allele can be common.

True

Different varieties of the same gene, called ______, may arise from mutations.

alleles

In the human genome, 22 of the 23 pairs of chromosomes are called

autosomes

In the nucleus of eukaryotic cells, all of the DNA is divided into multiple , which are continuous, long strands of DNA wrapped around proteins.

chromosomes

Long strands of DNA and their associated proteins are called

chromosomes

Homologous chromosomes are

chromosomes that look alike and have the same sequence of genes but may not carry the same alleles.

A human ______ cell has 46 chromosomes, 23 chromosomes from each parent.

diploid

In Mendel's studies, a ______ trait is one that could mask the appearance of another trait.

dominant

When one or both copies of a gene are the ______ allele, then this allele's form of the trait will be exhibited.

dominant

The gametes of humans are called

eggs and sperm

The first cell of a new organism is formed from the merging of haploid gametes during

fertilization