Biology Chapter 8 HW

Homologous chromosomes migrate to opposite poles during ______.

- Anaphase 1 (During anaphase 1 sister chromatids remain attached at their centromeres, and homologous chromosomes move to opposite poles)

If a hypothetical organism has 5 chromosomes in one of its gametes, then how many chromosomes must it have in a body cell just before mitosis?

- 10 chromosomes

A diploid organism whose somatic (nonsex) cells each contain 32 chromosomes produces gametes containing _______ chromosomes.

- 16 chromosomes (16 is half of 32)

Normal human gametes carry _____ chromosomes.

- 23 (This is the number of chromosomes in a single set of human chromosomes)

Which of these is NOT a carcinogen? A) Testosterone B) Cigarette smoke C) Fat D) UV light E) All of the above are carcinogens

- All of the above are carcinogens (Testosterone, cigarette smoke, fat, UV light are all substances that can cause cancer)

Chromosomes separate during _______.

- Anaphase

The sister chromatids separate and begin moving toward opposite poles of the cell during which phase of mitosis?

- Anaphase

Centromeres divide and sister chromosomes become full-fledge chromosomes during ______.

- Anaphase (During anaphase, sister chromatids separate and migrate to opposite poles)

During _____ sister chromatids separate.

- Anaphase 11 (Anaphase 11 is essentially the same as mitotic anaphase except that the cell is haploid)

What is the process called when a single individual is reproducing?

- Asexual reproduction

_______ reproduction is a means of creating new individual solely by _______, the form of cell division that creates genetically identical daughter cells.

- Asexual.......Mitosis

A ______ is a lump of abnormal cells that, although growing out of control, remains at its original site.

- Benign tumor

Bacteria divide by _____.

- Binary fission (Binary fission is the method used by bacteria to divide)

An individual with a malignant tumor is said to have ______.

- Cancer

Diploid

- Cell contains two complete sets of chromosomes (Mitosis)

Haploid

- Cell has only one set of chromosomes (Meiosis)

What structure joins sister chromatids?

- Centromere (The centromere is the point of attachment between two duplicated chromosomes)

Telophase

- Chromosomes become less condensed - New nuclear envelopes formed

Recombinant Chromosomes

- Composed of materials from both parents

At the end of the mitotic (M) phase, the cytoplasm divides in a process called ______.

- Cytokinesis

The first step of bacterial replication is ______.

- DNA replication (The DNA must be copied in order to proceed)

_______ is a carcinogen that promotes colon cancer.

- Fat (A diet high in fat increases the risk of both colon and breast cancer)

Meiosis starts with a single diploid cell and produces ______.

- Four haploid cells

Meiosis 11 produces ______ cells, each of which is _____.

- Four.....Haploid (At the end of meiosis 11 there are four haploid cells)

During prophase 1 of meiosis, ________.

- Homologous chromosomes stick together in pairs

During _____ the cell grows and replicates both its organelles and its chromosomes.

- Interphase

A cell preparing to undergo meiosis duplicates its chromosomes during ____.

- Interphase (Chromosomes are duplicated during interphase)

Nucleoli are present during _____.

- Interphase (Nucleoli are present during interphase)

A ______ is an abnormally growing mass of cells that is actively spreading through the body.

- Malignant tumor

Gametes are produced by ________.

- Meiosis (Meiosis produces haploid gametes from a diploid parental cell)

In the stages of meiosis what stage are haploid?

- Meiosis 1 and Meiosis 2 (Once meiosis 1 is complete, cells are haploid)

What stage of cellular reproduction has chromosomes lined up two-by-two?

- Meiosis 1 only (Meiosis 1 is the only time that chromosomes line up by homologous pairs)

Sister chromatids center during _______.

- Metaphase

The chromosomes line up in the center of the cell during which phase of mitosis?

- Metaphase

During _____ chromosomes align single file along the equator of a haploid cell.

- Metaphase 11 (Metaphase 11 is essentially the same as mitotic metaphase except that the cell is haploid)

_______ is the spread of cancer cells from their site of origin to other sites in the body.

- Metastasis

Prophase

- Microtubules form the mitotic spindle - The nuclear envelope breaks up

What process is going on in your hand right now?

- Mitosis (Mitosis takes place anywhere in the body)

Spindle fibers attach to kinetochores during ______.

- Prometophase (Attachment of spindle fibers to kinetochores is one of the events of prometaphase)

Mitotic spindle forms during _______.

- Prophase

The centrosomes move away from each other and the nuclear envelope breaks up during which phase of mitosis

- Prophase

Chromosomes become visible during _______.

- Prophase (During prophase, the chromatin fibers become discrete chromosomes)

During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur?

- Prophase 1 (Segments of nonsister chromatids trade places during prophase 1, resulting in recombination)

Synapsis occurs during _____.

- Prophase 1 (Synapsis, the pairing of homologous chromosomes, occurs during prophase 1)

The correct order of events during meiosis is: _______,

- Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, cytokinesis, meiosis 11

During ____ a spindle forms in a haploid cell.

- Prophase 11 (Prophase 11 is essentially the same as mitotic prophase except that the cells are haploid)

______ reproduction, in contrast, generates genetically unique offspring. To accomplish this, a organism must produce _____ ---sperm and egg--- through the process of _______. The cells produced this way will be ______, meaning that they contain a single set of chromosomes. Such cells are produced only in the _____.

- Sexual.......Gametes.........Mitosis.........Haploid........Gonads

Anaphase

- Sister chromatids separate and become full-fledged chromosomes that move to opposite poles

Cytokinesis often, but not always, accompanies ________.

- Telophase

The chromosomes arrive at the poles and nuclear envelopes form during which phase of mitosis?

- Telophase (Final stage of mitosis)

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids.

- Telophase 1

At the end of _____ and cytokinesis there are four haploid cells.

- Telophase 11

The nuclear envelope forms during ______.

- Telophase and cytokinesis

What is different concerning the DNA in bacterial cells as opposed to eukaryotic cells?

- The amount of DNA present - Whether the DNA is housed in a nucleus or not - Whether the DNA is linear or circular

What must happen before a cell can begin mitosis?

- The chromosomes must be duplicated (The chromosomes, or genetic material must be copied first)

Cytokinesis

- The cytoplasm divides

During _____ both the contents of the nucleus and the cytoplasm are divided.

- The mitotic phase (The mitotic phase encompasses both mitosis and cytokinesis)

Metaphase

- The mitotic spindle is fully formed - Chromosomes are lined up in the center of the cell

If the chromosomes are duplicated and lined up by homologous pair, what stage of cell reproduction are they in?

- The start of meiosis 1

During prophase a homologous pair of chromosomes consists of _______.

- Two chromosomes and four chromatids (At this point each of the chromosomes consists of two chromatids)

Meiosis 1 produces ______ cells, each of which is _____.

- Two.....Haploid (At the end of meiosis 1 there are two haploid cells)

Interphase

- Where most of the cell's life is spent - When growth occurs - Cells that are about to divide replicate their DNA