Chapter 3 Genetics

two pairs of sister chromatids

A bivalent consists of

Two sets of chromosomes

A diploid cell is defined as a cell that has

A set of chromosomes

A haploid cell is represented by 1n and a diploid cell by 2n. The n refers to

Autosomes

A human cell contains two main types of chromosomes sex chromosomes and

Somatic

A____-cell is any cell of the body that is not a gamete or precursor to a gamete

Locus

A____refers to the physical location of a gene

Chromatids

After replication each chromosome consists of two copies called

The chromosomes become visible with the light microscope

All of the following events occur during prometaphase except

The pairs of sister chromatids begin to separate from each other

All of the following events occur during telophase except

Karyotype

An organized presentation of the chromosomes within a cell is called an

The connections that result from crossing over

Chiasmata refers to

Three chromosomes and six chromatids

Consider an organism that has three pairs of chromosomes. At the start of meiosis 2, each cell would have

Chromosome segregation

Defects in crossing over appear to cause abnormalities in

Secondary oocyte

During ovulation in female mammals the_____is released from the ovary into the oviduct. If a sperm then penetrates this cells it is stimulated to complete meiosis 2

Metaphase of meiosis 1

During which of the following phases are tetrads organized at random along a plate in the center of the cell

Centrioles

Each centrosome of an animal cell contains a pair of____at right angles to each other

True

Each species has a particular chromosome composition

Meiosis

Eukaryotic cells that are diploid can divide by______to produce haploid sex cells

Oogenesis

Female animals produce egg cells by a process called

Endosperm

Fertilization in plants involves the formation of a triploid(3n) cell. This cell undergoes repeated mitotic divisions to produce______ which serves as a nutrition source

Gametogenesis

Gametes or sex cells are produced by a process called

Linked

Genes that are physically located on the X chromosome are called X_____genes

Four

How many haploid cells are produced from one primary spermatocyte in the process of spermatogenesis

Testcross

In a Drosophila melanogaster____a fly with a dominant phenotype and unknown genotype is mated to one that has a recessive phenotype

Homolog

In a diploid cell each member of a pair of chromosomes is called an

Lysosomes

In eukaryotes the____is an organelle that plays a role in the degradation of macromolecules

Less

In eukaryotes, diploid cells can divide by a process called meiosis, This word is derived from the Greek term for

Organelles

In eukaryotes_____are membrane bound structures that have specific functions

Embryo Sac

In flowering plants the female gametophyte is a seven celled structure called the

Ovules

In flowering plants the female gametophytes are formed within structures called______which are found in the ovaries

Megasporocyte-Megaspore-Embryos sac

In flowering plants the formation of female gametes occurs via the following

Microsporocyte-Microspore-pollen grain

In flowering plants the formation of male gametes occurs via the following

Pollen grain

In flowering plants the male gametophyte with a thick cell wall is called

Ovule, Ovary

In flowering plants the process of fertilization ultimately results in the______developing into a seed while the surrounding_____forms the fruit which contains one or more seeds

Polar Body

In human oogenesis the first meiotic division is asymmetrical and produces a secondary oocyte and a much smaller known as a

Not considered homologous even though they do have short regions of homology

In humans the X and Y chromosomes are

Heterogametic,Homogametic

In humans the male is known as the___sex because one type of sperm carries only the X chromosome and another type carries the Y chromosome. The female on the other hand is the_____sex because all eggs carry a single X chromosome

Leptotene

In prophase 1 of meiosis the replicated chromosomes begin to condense and become visible with a light microscope during which phase

Fungi, Algae

Isogamous organisms are mainly found among which of the following

Spermatogenesis

Male animals produce mature sperm by a process called

Binary Fission

Most bacteria cells divide by

Heterogamous

Most eukaryotic species are_____which means they produce two gametes with different morphologies

46

Most human somatic cells contain a total of_____chromosomes

Ferns and nonvascular plants

Multiple flagella are more likely to be found in the sperm of

Eukaryotes

Organisms such as protists and fungi that have a true nucleus are called

Nucleoid

Prokaryotes usually have a single type of circular chromosome in a region of the cytoplasm called the

Prophase, Prometaphase, Metaphase, Anaphase, Telophase

Rank the phases of mitosis in order starting with the earliest at the top

The nuclear membrane begins to dissociate into small vesicles, The chromatids become condensed, The mitotic spindle begins to form, The nucleolus becomes less visible

Select all of the following events that occur during prophase

Pachytene

Synapsis is complete and crossing over occurs during which stage of prophase 1 of meiosis

Homologous chromosomes recognize each other and begin to align themselves in prophase 1

Synapsis is the process by which

Spermatogonial cells

The earliest precursors to sperm cells are called

Four phases G1,G2,S and M

The eukaryotic cell cycle is composed of

False

The gametophyte of flowering plants tends to be large while that of mosses is typically small

Crossing Over

The interchange of corresponding chromatid segments of homologous chromosomes during prophase 1 of meiosis is called

Gametophyte, Sporophyte

The life cycle of plant species alternate between haploid and diploid generations. The haploid generation is called the_____whereas the diploid generation is called the

Formed before birth but are arrested in prophase 1 of meiosis

The primary oocytes of a human female are

Distribute the replicated chromosomes equally into the two daughter cells

The primary purpose of mitosis is to

Sequencing the DNA

The procedure for making a karyotype includes all of the following steps except

False

The sequence of bases of one homolog typically differs by less than 0.1% relative to the sequence of the other homolog

Chromosomes

The structure within all living cells that contain the genetic material are called

Centromere

The two chromatids of a chromosome are joined together at a region of DNA called the

Alleles

The two members of a homologous pair of chromosomes may carry different versions of a given gene which are called

Anaphase

The______stage of meiosis 1 is characterized by the separation of the two pairs of sister chromatids within a bivalent from each other and their migration to opposite poles of the cell

Asexual

Unicellular prokaryotic organisms proliferate by_____reproduction in which a preexisting cell divides to produce two new cells

A single set of chromosomes

What does a haploid cell contain

The field of genetics that involved the microscopic examination of chromosomes

What is cytogenetics

It contains digestive enzymes that allow the sperm to penetrate the eggs outer protective layers

What is the role of the acrosome of a sperm

Twice as many chromatids as chromosomes

When S phase is completed a cell has___in the G1 phase

G0,G1,G2,S

Which of the following are part of interphase

Proteins, DNA

Which of the following are the major components of a chromosome

A mother cell divides to produce two identical daughter cells

Which of the following best describes asexual reproduction

One pair of sister chromatids is linked to one pole and the homologous pair is linked to the other

Which of the following best describes how chromosomes are attached to microtubules during metaphase 1 of metaphase 1 of meiosis

Each homologous pair of sister chromatids migrates to opposite poles

Which of the following best describes the events of anaphase 1 of meiosis

An organelle of eukaryotes that is surrounded by two membranes

Which of the following best describes the nucleus

2n---1n

Which of the following best describes the outcome of meiosis 1 in humans

Sister chromatids separate from eachother and head to opposite poles

Which of the following events occur during anaphase of mitosis

Mitochondria, Chloroplast

Which of the following organelles contain their own DNA

Golgi body, Endoplasmic reticulum

Which of the following organelles play a role in protein modification and trafficking

Leptotene, Zygotene, Pachytene, Diplotene, Diakinesis

Which of the following represents the correct order of stages of meiotic prophase 1

Most eukaryotic species are diploid or have a diploid phase to their life cycle

Which of the following statements about eukaryote is true

Animals produce gametes by meiosis while plants produce gametes by mitosis

Which of the following statements about gametes is true

Mitosis produces 2 diploid daughter cells while meiosis produces four haploid daughter cells

Which of the following statements about mitosis and meiosis of humans is true

Both synapsis and crossing over occur in prophase 1 of meiosis

Which of the following statements about synapsis and crossing over is true

Male is XY and the female is XX

Which of the following statements about the X-Y system of sex determination is true

The anthers of the sporophyte produce the male gametophyte while the ovaries of the sporophyte produce the female gametophyte

Which of the following statements about the life cycle of flowering plants is true