Genetics Chapter 1 Achieve

Ace your homework & exams now with Quizwiz!

In a diploid organism with 12 chromosomes, how many different arrangements of chromosomes can be generated by independent assortment?

-64 -The number of different chromosomal arrangements possible through independent assortment can be calculated using the formula 2𝑛, where 𝑛 represents the number of homologous chromosome pairs. -Therefore, a diploid organism with 12 chromosomes would have 6 homologous pairs leading to 26 or 64 possible chromosomal arrangements on the metaphase plate during meiosis I.

Gene

-A Short segment of a chromosome that codes for an RNA molecule -A functional unit of heredity

Which statements describe Y‑linked traits?

-All male offspring of affected fathers will express the trait. -The trait is passed down to a son by his father.

Nucleic acids

-DNA and RNA are nucleic acids. -Nucleic acids are strands of nucleotides that have been joined together -The nucleic acid DNA is one component of chromosomes.

some limitations of current genetic testing

-For example, genetic testing is restricted by the body of knowledge that is available regarding genetic mutations that are associated with genes. -In most cases, only common variants can be identified with standard markers, meaning an individual with a rare variant that causes the same effect may go undetected by these tests. -Additionally for many diseases, genetic testing can only account for predisposition or genetic risk. It also cannot account for potential external factors, such as environmental effects. -Genetic testing provides a diagnosis or level of risk. After that, it is up to the individual and his or her doctor to identify the best method for treatment. -Current genetic tests typically do not treat a disease nor aid in the identification of the best course of treatment.

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Examination of the nucleotide sequence found at the end of chromosomes

-Molecular genetics

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Mechanisms that ensure a high degree of accuracy during DNA replication

-Molecular genetics

mitochondrion (plural: mitochondria)

-Much of the cell's energy metabolism takes place in the mitochondria , which is another organelle with a double membrane. -A single eukaryotic cell contains many mitochondria. Mitochondria are usually depicted as cylinders with a highly folded inner membrane. They are often found in association with cytoskeletal microtubules

metaphase I

-Pairs of homologous chromosomes then line up across the center of the cell in metaphase I.

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Effect of nonrandom mating on the distribution of genotypes among a group of animals

-Population genetics

Many genetic studies, particularly those of recessive traits, have focused on small isolated human populations, such as those on islands. Which are major advantages that isolated populations might provide for the study of recessive traits?

-Some recessive traits that are rare in most large populations may be relatively common in some small populations. -Inbreeding, which is more common in small populations, will tend to increase the frequency of recessive phenotypes.

anaphase I

-The sister chromatids remain attached to each other as the homologous pairs separate in anaphase I.

Define blending inheritance and contrast it with preformationism.

-The theory of blending inheritance proposes that the egg and sperm from two parents contains material that blends upon conception, influencing the development of the offspring. -This theory indicates that the offspring is an equal blend of the two parents. blending inheritance proposed that offspring would always have traits in between the range of the parents' traits -In preformationism, the offspring inherits all of its traits from one parent.

Chromosome

-Threadlike DNA molecules that are visible during meiosis -Large genetic element that carries genes essential to function

How many chromatids and how many strands of DNA are present in paired homologous chromosomes?

-When homologous chromosomes pair in prophase I, each chromosome consists of 2 identical sister chromatids. -Each chromatid is a single molecule of DNA consisting of 2 antiparallel DNA strands. Therefore, paired homologous chromosomes consist of 4 chromatids made up of 8 strands of DNA.

Inheritance of acquired characteristics

-also called Lamarckian inheritance -proposes that the traits an organism gains over its lifetime can be passed on to its offspring. -For example, an individual that trained hard and became very muscular would have more muscular offspring. -In other words, using a characteristic could affect the genetic information and the inheritance of a trait and make it more likely to be passed on.

chromatin

-an association of DNA and proteins that keep the DNA wound in a condensed state -Before a cell divides, the chromatin condenses and the chromosomes become visible under a light microscope.

The endoplasmic reticulum

-both smooth and rough, is responsible for protein transport and some protein processing. -Ribosomes bind to rough endoplasmic reticulum, giving it a bumpy appearance.

Which process results in sister chromatids that are no longer identical? All of the answers are correct

-crossing over -Meiosis begins with each chromosome consisting of two identical double-stranded DNA molecules, the sister chromatids. -The homologous chromosomes pair early in prophase I, becoming aligned gene-for-gene along their length. -Crossing over between two non-sister chromatids of the homologous chromosomes can result in exchange of alleles of genes. -The result is that the two sister chromatids (still attached at the centromere) no longer are identical in allele content. -Random assortment of homologous chromosomes at the metaphase plate in metaphase I does not result in exchange of information by the non-sister chromatids. -Thus, in the absence of crossing over, the two sister chromatids of a chromosome remain identical to each other.

During meiosis I:

-homologous pairs of chromosomes split up and the cell divides into two new haploid cells that contain one copy of each duplicated chromosome. -Each duplicated chromosome has two sister chromatids that have not separated yet, forming an X‑shape.

What happens during meiosis

-meiosis, which involves two divisions of a parent cell. Meiosis gives rise to four daughter cells that have half the number of chromosomes as the parent cell. -These daughter cells become gametes, or sex cells, and do not divide again. -Cells produced from meiosis are genetically different from one another and the parent cell.

Crossing over shuffles alleles on

-non-sister chromatids of homologous chromosomes -Crossing over normally occurs only between the paired homologous chromosomes in the same meiotic cell. -Only crossing over b/n non-sister chromatids with different alleles of a locus results in genetically recombinant chromatids. -When crossing over occurs between the sister chromatids, identical alleles are exchanged and this does not produce new allele combinations.

Pangenesis

-proposes that all of the various cells of the body contain different genetic information that is transmitted to the reproductive cells and is thereby passed on to the next generation. -The implication is similar to the inheritance of acquired characteristics because both theories propose that traits gained in an individual's life could be passed on to the next generation.

Germ‑plasm theory

-proposes that each reproductive cell contains a complete set of genetic information -Somatic cells would not contribute to heredity and so any changes to somatic cells would not affect the germ cells. -Thus, only germ cells contribute to the next generation.

The haploid chromosome number

-represented by n -equal to the number of unique chromosomes in the nucleus of a cell.

Maintaining the integrity of the chromosomes, generation to generation, requires specialized sequences called __________________.

-telomeres -Each chromosome has a pair of telomeres, with one at each end of the chromosome. -Therefore, each chromosome contains two pairs of telomeres. -The haploid cell contains two pairs of telomeres, whereas the diploid cell contains four pairs of telomeres.

Suppose that life exists elsewhere in the universe. All life must contain some type of genetic information, but alien genomes might not consist of nucleic acids or have the same features as those found in the genomes of life on Earth. What might be the common features of all genomes, no matter where they exist?

-the ability to store the entire set of information an organism needs for reproduction and development -the ability to replicate the genetic information accurately for the next generation

In both haploid and diploid cells, one of the early events in prophase involves ...

-the migration of two pairs of centrioles to opposite ends of the cell -Centrioles are situated outside the nuclear envelope in an area of the cytoplasm called the centrosome. -The centrosome facilitates the formation of the mitotic spindle. -Both haploid and diploid cells contain the same number of centrosomes.

Cells are categorized as either prokaryotic or eukaryotic. Classify the characteristics as being unique to prokarytoic cells, common to both cell types, or unique to eukaryotic cells.

1) Relatively small, typically less than 10 micrometers in size 2) lack a true cytoskeleton

Cells are categorized as either prokaryotic or eukaryotic. Classify the characteristics as being unique to prokarytoic cells, common to both cell types, or unique to eukaryotic cells.

1) contain DNA 2) use ribosomes to synthesize proteins.

Which statements are true regarding how advancements in genetics have impacted society today?

1. Genetic testing has brought attention to our legislation on individual biological privacy. 2. Animal model manipulation has expanded our understanding of human disease. 3. Industrial services have decreased their environmental footprint to decrease harmful by‑products of oil production.

Which practices in agriculture and animal domestication demonstrate a rudimentary understanding of heredity and genetics?

1. Primitive societies were more likely to kill wolves that were too aggressive and keep the less aggressive ones as pets and hunting companions. 2. Farmers planted seeds from trees that produced the largest, sweetest fruits and not from trees that produced the smallest or inedible fruits. 3. Nomads selected the chickens that laid the most eggs for breeding.

Which of the statements are reasons why kangaroos would be a poor choice as model organisms for studying ovarian cancer?

1. They are marsupials and are too different from other mammals for studying. 2. They are needlessly large when smaller, more easily handled organisms, such as mice, are available. 3. They produce very few offspring at a time and thus require a lot of time to collect meaningful data.

What are the functions of mitotic cell division?

1. growth of multicellular organisms 2. asexual reproduction 3. cell regeneration

In prophase: the haploid cell contains _______________________, whereas the diploid cell contains ________________________.

1. one pair of sister chromatids 2. two pairs of sister chromatids

Important checkpoints include

1.) G1/S checkpoint -which occurs during G1prior to the S phase 2.) G2/M checkpoint -which occurs in G2 prior to mitosis 3.) spindle‑assembly checkpoint -Which occurs during mitosis.

Which of the statements are ways that modern geneticists are addressing medical, social, or industrial problems?

1.studying viral genetics to learn how to control the spread of infectious diseases 2. improving the nutritional value of agricultural crops through genetic modification 3. developing genetic tests for conditions so that patients can receive appropriate preventive care

In a given homologous chromosome pair, how many recombinant chromatids are generated by a single crossover event?

2 -A single crossover event involves only two of the four homologous chromatids in a paired set of homologous chromosomes. -At the conclusion of the event, two of the four chromatids are recombinant while the other two remain nonrecombinant.

A diploid cell contains

2n chromosomes, or a pair for each n. -During interphase, each chromosome is duplicated to form a pair of sister chromatids attached together at the centromere. -Chromosomes can be visually observed after condensation occurs during prophase.

In the absence of crossing over, which formula best represents the number of possible different arrangements of chromosomes generated by independent assortment?

2𝑛, where 𝑛 represents the number of homologous chromosome pairs per cell entering meiosis

Human cells, for example, have _____________ chromosomes

46 - in females, there are 23 homologous pairs; in males, 22 pairs are homologous, and the last pair (X and Y chromosomes) is only partially homologous

homologous pair

A pair of chromosomes that are alike in structure and size and that carry genetic information for the same set of hereditary characteristics. One chromosome of a homologous pair is inherited from the male parent, and the other is inherited from the female parent.

How do Multicellular organisms use mitotic cell division to grow?

All multicellular organisms start as a single cell and undergo multiple rounds of mitotic cell division to become multicellular. -These types of cell divisions multiply the number of cells in the organism, increasing the size of the organism. -In bacteria, cell division is called binary fission. -Single‑celled eukaryotes, such as yeast, use mitotic cell division to reproduce --> This type of reproduction is called asexual reproduction.

Cell theory began to develop in 1839, following the research of Matthias Schleiden and Theodor Schwann into plant and animal tissues. Both the botanist Schleiden and the physiologist Schwann noticed that every organism they viewed under a microscope, whether plant or animal, was composed of cells. Their observations that all living species are made up of one or more cells led to the early formation of cell theory. Which tenet of cell theory is described by the paragraph about the historical observations of cells?

All organisms are composed of one or more cells.

Variants of Genes are called ____________________

Alleles.

Which of the statements cannot occur with X‑linked dominant inheritance for a rare trait?

An affected man can pass on the trait to his son.

What takes place in mitochondria

Cellular respiration takes place in mitochondria

components of centrosomes, which assemble the microtubules of the mitotic spindle

Centrioles

Given observations of a family, identify the best‑supported conclusion about genetic versus environmental trait determination. A.) Among non‑identical siblings, one sibling was prenatally exposed to a known teratogen and born with birth defects. Conclusion: genetic factors caused the birth defects. B.) Non‑identical siblings with intact hearing are the biological offspring of parents who are deaf. Conclusion: environmental factors caused deafness in the parents. C.) Identical twins raised by their biological parents both have a specific congenital heart defect that neither parent has. Conclusion: environmental factors caused the congenital heart defects. D. )Identical twins separated at birth and raised in different parts of the country both have a severe form of asthma that neither biological parent has. Conclusion: genetic factors caused the asthma. E.) A child develops early‑onset cataracts that the maternal grandmother also developed, and both individuals were delivered in the same hospital. Conclusion: environmental factors caused the cataracts.

D. )Identical twins separated at birth and raised in different parts of the country both have a severe form of asthma that neither biological parent has. Conclusion: genetic factors caused the asthma.

_______________ and ________________ together make up Chromosomes.

DNA & Proteins

What happens during mitosis

During mitosis, the nucleus and cytoplasm of the parent cell divide, and each daughter cell receives an identical set of the copied DNA. -The genetically identical daughter cells have the same number of chromosomes as the parent cell.

T/F: Mitotic cell division is used to produce gametes.

F: Gametes are produced by a different type of cell division called meiosis

Genes make up the ______________

Genome. They are encoded in DNA and are located on Chromosomes

What is the germ plasm theory?

Germ‑plasm theory states that each cell contains the complete genetic code for its species, including cells in the gonads that produce gametes. This theory is widely accepted as the physical basis of inheritance.

Match the scientists with their seminal work: Rules of inheritance

Gregor Mendel

When did Charles Darwin publish his theory on natural selection?

In 1859, Charles Darwin published the theory of natural selection that underlies the theory of evolution, based on his observations of the wildlife of the Galapagos Islands. He proposed that any trait within a population that is beneficial to an organism's survival and reproduction will be maintained. Natural selection describes the change in frequency of traits based on the differential reproductive success of individuals with specific traits.

What did Thomas Hunt Determine in 1910?

In 1910, Thomas Hunt Morgan discovered that genes are contained within chromosomes. He determined that genes are the physical units responsible for the principles of heredity. --Thomas Hunt Morgan's pioneering work was conducted with a new model organism, Drosophila melanogaster, which was not in use experimentally before the 1900s.

When did Gregor Mendel publish his experiments?

In the 1850s and 1860s, Gregor Mendel performed a series of experiments by breeding pea plants and calculating the ratios of offspring with specific traits. Through this series of experiments, he was able to develop a theory of the principles of heredity that governed the traits. Although all traits do not follow the principles Mendel formulated, the pattern he discovered is known today as Mendelian inheritance.

Consider two cells, where one cell is haploid and the other is diploid. Which of the following differences between the two cells is observed during prophase of mitosis?

In the haploid cell, only one pair of sister chromatids are present, whereas in the diploid cell, two pairs of sister chromatids are present.

Is it possible to generate four recombinant chromosomes from a single homologous chromosome pair during a single meiosis? If so, how?

It is possible to generate four recombinant chromosomes from a single homologous chromosome pair if two separate crossover events take place on different non‑sister chromatids. -Although each crossover event will only generate two recombinant chromatids from a homologous chromosome pair, two independent crossover events involving two sets of non-sister chromatids in a single homologous chromosome pair will generate four recombinant chromosomes at the completion of meiosis.

Match the scientists with their seminal work: Theoretical three‑dimensional DNA structure

James Watson and Francis Crick

Match the scientists with their seminal work: Polymerase chain reaction

Kary Mullis

What make up chromosomes.

Long molecules of DNA

Match the scientists with their seminal work: Cell theory

Matthias Schleiden & Theodor Schwann

What are the major sites of energy production.

Mitochondria and chloroplasts are

What does mitosis ensure?

Mitosis ensures that the duplicated chromosomes, in the form of sister chromatids, are distributed evenly to the daughter cells

No DNA replication takes place between ______________ & _________________

No DNA replication takes place between meiosis I and meiosis II.

Allele

One of the different forms of a gene that exist at a single locus

What does pangenesis predict?

Pangenesis predicts that genetic information within individual cells varies according to the structure and function of a particular cell -For example, muscle cells carry the genetic code for muscles, whereas nerve cells carry the genetic code for nerve structure and function. -Pangenesis is discredited as a valid explanation for how heritable information is incorporated into gametes.

What is preformationism?

Preformationism states that inside each gamete is a very small offspring, called a homunculus, that develops simply by enlarging. The homunculus is female if inside an egg or male if inside a sperm; therefore, daughters receive their complete genetic code from their mothers and sons receive their complete genetic code from their fathers. Preformationism is discredited as a valid explanation of the nature of inheritance.

_______________________- reform in prophase II

Spindle fibers

A section of Elodea leaf is stained and examined under a microscope. The total number of cells in each stage of the cell cycle is recorded and presented in the table. If the complete cell cycle in an Elodea leaf requires 24 hours, what is the average duration of metaphase in the cycle? Assume no cells are in Go.

Step 1: calculate the proportion of cells in metaphase by dividing the number of cells in each phase by the total number of cells --> (5 cells in metaphase)/192 cells total = 0.026 of the total cells are in metaphase -give the average number of cells in metaphase compared to all cells Step 2: to find the average duration of time metaphase takes to complete, simply multiply the proportion of cells in metaphase by the total time an Elodea leaf cell takes to complete the cell cycle (24 hours) --> 0.026 of all cells in metaphase×24 hours to complete the cell cycle=0.625 hours to complete metaphase

T/F: DNA cannot be used as a template for direct amino acid synthesis

T

T/F: . When you get a cut on your skin, mitotic cell division produces the cells that repair the wound.

T: Mitotic cell division also functions to replace or regenerate cells that may be old or wounded

Who developed the concept of inheritance of acquired characteristics?

The ancient Greeks developed the concept of inheritance of acquired characteristics, which states that offspring inherit environmentally determined traits from their parents.

A cell has a circular chromosome and histone proteins associated with its DNA, but lacks a nuclear membrane. Choose the domain of the cell with the best justification.

The cell belongs to Archaea because it has histone proteins, which are present in Archaea and Eukaryota but absent in Eubacteria.

In anaphase

The centromeres divide, and the sister chromatids of each chromosome are pulled apart to opposite poles of the cell by the spindle fibers

Finally, in telophase

The chromosomes are completely separated to the opposite poles of the dividing cell. -Nuclear membranes reform around the chromosomes, and the chromosomes revert to their diffuse, loosely packed form.

Describe what makes up the DNA backbone

The deoxyribose and phosphate components of the nucleotide form the backbone of a DNA molecule. The deoxyribose of one nucleotide bonds with the phosphate group of an adjacent nucleotide. This repeating deoxyribose-phosphate pattern makes up the DNA backbone.

What does the blending inheritance theory state and how is this different from preformationism?

The egg and sperm contain genetic material that mixes upon conception to produce an intermediate phenotype in the offspring.

M-Phase

The phase of the cell cycle that includes mitosis and cytokinesis. -The process of nuclear division by cytokinesis

anaphase II

The sister chromatids separate and migrate along the spindle fibers toward the poles of the cell. -After the sister chromatids separate in anaphase II, they are considered individual chromosomes.

__________________________ produced during meiosis I enter meiosis II.

The two haploid cells

How did 17th and 18th century botanists contribute to the rise of modern genetics?

They developed techniques for experimental plant hybridization.

Which statement describes the central dogma of biology?

Transcription is the process of synthesizing RNA from DNA. Translation is the process of synthesizing an amino acid sequence from RNA

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Study of the inheritance of traits encoded by genes on sex chromosomes (sex-linked traits) differs from the inheritance of traits encoded by genes on nonsex chromosomes (autosomal traits)

Transmission genetics

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Analysis of pedigrees to determine the probability of someone inheriting a trait

Transmission gentics

what's produced at the end of telophase I and cytokinesis

Two haploid cells produced at the end of telophase I and cytokinesis -contain two sister chromatids from a single chromosome of each homologous pair.

Which genetic condition is found at an unexpectedly high frequency among the Hopi Native Americans?

albinism

If a man exhibits a Y‑linked trait, what proportion of his sons should also be affected?

all

RNA is translated into a__________________________

an amino acid sequence.

What is the most inclusive definition of a model organism (model system)?

an organism with a biological system that is representative of the same system in other organisms

Ribosomes

are complexes of RNA and proteins on which translation from RNA to protein takes place. -They are not enclosed by membranes within the cell - Ribosomes bind to rough endoplasmic reticulum, giving it a bumpy appearance.

Lysosomes

are organelles that contain digestive enzymes, which can digest food particles taken into the cell or break down worn‑out cellular components. Lysosomes can also release their enzymes outside of the cell, where the enzymes break down extracellular material.

Genetic tests have greatly enhanced our understanding of complex human diseases. However, there are still some limitations. Select the caveats of current genetic tests when analyzing common complex human diseases.

can only identify most common variants do not consider environmental influences do not provide a treatment, only a diagnosis

Is this describing a gene, chromosome, or genome? -is a contiguous piece of DNA -is a unit of DNA carrying genetic information encoded in genes -functions to package, organize, and regulate access to DNA -is the largest molecule in the cell -is a linear or circular molecule

chromosome

What are the structures in a cell that group genes together, are composed of chromatin (DNA and protein), and become visible under a light microscope during mitosis?

chromosomes

The spindle‑assembly checkpoint

confirms that each chromosome is aligned on the metaphase plate and properly attached to spindle fibers from opposite poles of the cell.

The cytoskeleton

consists of fibers that enable movement and transport within the cell.

Mitosis is followed by _____________

cytokinesis, or the partitioning of cytoplasm between the two newly formed daughter cells.

Molecular genetics

deals with the chemical nature of genes. Replication, transcription, translation, and the regulation of genes are all included within molecular genetics. Molecular genetics also includes the physical structure, organization, and function of genes.

. When checkpoints are missing or defective... what do defective cells do?

defective cells can replicate and disease states can result. One of these diseases is cancer, or uncontrolled growth of cells.

In Drosophila melanogaster, the level of expression of genes on the X chromosome in males is doubled. What phenomenon is this an example of?

dosage compensation

The G2/M checkpoint

ensures that DNA has been replicated without error.

Population genetics

focuses on groups composed of organisms of the same species, rather than the individual. Specifically, population genetics deals with the genetic composition of the population and how it changes with time or location. Therefore, population genetics studies the evolution of genes in a population.

Is this describing a gene, chromosome, or genome? -determines a particular characteristic of an organism -codes for a specific protein or RNA -acts as the basic unit of heredity

gene

Is this describing a gene, chromosome, or genome? -may include plasmids -describes the collection of all replicable genetic material of a cell or organism -Each organism has one -encodes all the heritable traits of an organism

genome

Archaea and Eukaryota both have ________________________________, a trait Eubacteria lack

histone proteins associated with their DNA

The G1/S checkpoint

holds the cell in G1 until the components needed for DNA replication have been manufactured

Transmission genetics

includes the relationship between chromosomes and heredity. For example, gene mapping is included within transmission genetics. In other words, where did an individual's genes come from and how would that individual pass on their genes?

What are the two processes in meiosis that create genetic differences among cells?

independent assortment and crossing over -Genetic diversity among meiotic products (gametes) is generated by both independent assortment of homologous chromosomes on the metaphase plate, and crossing over of non‑sister chromatids.

What concept proposes that traits acquired in a person's lifetime become incorporated into that person's hereditary information and are passed on to offspring?

inheritance of acquired characteristics

Chromosomes are replicated in ____________, before meiosis begins.

interphase

M phase

is a period of active cell division.

Centromere

is the part of the chromosome that appears constricted. It is the area where sister chromatids are linked, and it is the area that attaches to the mitotic spindle during mitosis.

What is the complete set of genetic instructions for an organism?

its genome

During which phase of meiosis does independent assortment occur?

metaphase I -Paired homologous chromosomes line up on the metaphase plate during meiosis I, but the arrangement of paternally and maternally derived chromosomal homologs is random with respect to which chromosome will go to the right or left of the metaphase plate. This random arrangement of paternally and maternally derived chromosomes is the mechanism of independent assortment.

The Golgi apparatus

modifies and "packages" proteins for transport out of the cell or to other parts of the cell. Transport vesicles containing the packaged proteins pinch off from the Golgi apparatus and move to lysosomes, storage vesicles, or the plasma membrane.

The study of the chemical nature of the gene, and how genetic information is replicated and expressed, is part of what division of genetics?

molecular genetics

Crossing over shuffles alleles on

non-sister chromatids of homologous chromosomes

Cells are categorized as either prokaryotic or eukaryotic. Classify the characteristics as being unique to prokarytoic cells, common to both cell types, or unique to eukaryotic cells.

nuclear membrane surrounds DNA

Each of the four haploid cells produced during telophase II and cytokinesis has ...

one chromosome from each homologous pair in the original cell.

Interphase

period of growth and development between cell divisions.

For each of the following genetic topics, indicate whether is focuses on transmission genetics, molecular genetics, or population genetics: Study of people on a small island to determine why a genetic form of asthma is so prevalent on the island

population genetics

What division of genetics is essentially a study of evolution?

population genetics

Do eukaryotes or prokaryotes localize DNA in the cytoplasm?

prokaryotes

Archaea and Eubacteria are also collectively called ________________

prokaryotes -a historical grouping based on the presence of circular chromosomes and the absence of nuclear membranes, in contrast to the eukaryotes, which have nuclei and linear chromosomes.

During which phase of meiosis does crossing over occur?

prophase I -Non‑sister chromatids undergo crossing over during prophase I. This is the stage when homologous chromosomes initiate pairing. Although the homologous chromosomes remain associated until anaphase I, all genetic exchange between homologs is restricted to prophase I.

Meiosis I begins with ________________

prophase I. -The chromosomes condense and form homologous pairs. -The arms of non-sister chromatids in homologous pairs cross over and exchange genetic material at this point.

Mitosis consists of four major stages

prophase, metaphase, anaphase, and telophase

Checkpoints function to ensure ...

that all the cellular components, such as proteins and chromosomes, are present and functioning before the cell moves to the next stage of the cell cycle. If components are missing or not functioning, the checkpoint will prevent the cell from moving to the next stage. The checkpoints prevent defective cells from replicating.

A set of Alleles help determine__________________________

the Genotype.

The Genotype and Environmental factors help determine_________________________

the Phenotype.

In metaphase

the chromosomes align at the equator of the cell. There, the centromeres of each chromosome attach to spindle fibers.

In prophase

the chromosomes condense from relatively diffuse chromatin into highly compacted structures composed of identical sister chromatids joined by a centromere. The nuclear membrane remains intact until it breaks down at the end of prophase. In metaphase, the chromosomes align at the equator of the cell. There, the centromeres of each chromosome attach to spindle fibers.

Which of these describes a genome?

the collection of genetic material in a cell or organism

. During metaphase II

the duplicated chromosomes migrate to the center of the cell individually and not as pairs as they did in metaphase I.

. The blueprint for the entire organism must be contained within ________________

the genome of each reproductive cell.

Genetic information is stored in_________________ which has a double membrane.

the nucleus

The major difference between eukaryotic cells and prokaryotic cells is...

the presence of membrane‑bound organelles in eukaryotes. These include the nucleus, mitochondria, and chloroplasts.

How does the structure of DNA encode genetic information?

the sequence of bases

During meiosis 2:

these sister chromatids separate, resulting in four haploid cells.

Cell division by mitosis is a mechanism of asexual cell replication. Some single‑celled organisms reproduce by cell division, and cell division enables multicellular organisms to grow and to repair damaged cells. Which is a product of cell division by mitosis?

two cells genetically identical to the original cell

Mitotic cell division produces

two daughter cells that are genetically identical to both the parent cell and to each other. This method of cell division has several functions.

Preformationism

was a popular theory that came about during the advent of the microscope, in which the sperm or egg contained a tiny, fully formed adult, called a homunculus, that simply grew in size during development. Because the organism was already fully formed within, traits would be inherited from a single parent only.


Related study sets

World Geography Chapter 12 Test Review

View Set

Chapter 18 - Hair Removal - Milady's Standard Esthetics

View Set

MKT 574: Chapter 5: CRM, Big Data, and Marketing Analytics

View Set

Chandra (Moon) - Important Degrees for Navamsha

View Set

recent European history- midterm study

View Set

Psychology Exam 2 Naturalistic observation

View Set

CHEM111 4.1-4.3, 4.4-4.5, 4.6-4.7

View Set