Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Biology 1543
Chapters 8
| Term | Definition |
|---|---|
| Cell division | Reproduction at the cellular level, requires the duplication of chromosomes, and sorts new sets of chromosomes into the resulting pair of daughter cells. |
| Chromosomes | The structures that contain most of the cells DNA |
| Asexual reproduction | Creation of genetically identical offspring by a single parent. (ex. Sea star species). Lone parent and each offspring have have identical genes. |
| Sexual Reproduction | Requires fertilization of an egg by a sperm. Testes and ovaries. Takes half of the genes from both parents.Not Identical. |
| Mitosis | A process, The type of cell division responsible for asexual reproduction and for the growth and maintenance of multicellular organisms. |
| Meiosis | The production of egg and sperm cells involves a special type of cell division. Produces haploid gametes in diploid organisms |
| What function does cell division play in an amoeba? In your body? | Reproduction; Growth, development, and repair. |
| Prokaryotes reproduce by a cell division called | Binary Fission |
| Chromatin | DNA in its loose state. DNA in one cell would exceed my own height. |
| As a cell prepares to divide its chromatin | Coils up |
| Sister Chromatids | Each chromosome that consist of two copies of DNA molecules, Creating daughter cells. |
| In humans, 46 chromosomes is equal to how many chromatids? | 92 chromatids |
| When does a chromosome consist of two identical chromatids? | When the cell is preparing to divide and has duplicated its chromosomes but before the duplicates actually separate. |
| What cycle multiplies cells? | The cell cycle |
| The process of cell division is a key component of the | Cell cycle |
| Cell cycle | An ordered sequence of events that extends from the time a cell is first formed from a dividing parent cell until its own division into two cells |
| The cell cycle consist of two main stages. | A growing stage (interphase) and the actual cell division (mitotic phase) |
| Interphase stage | when the cell roughly doubles everything in its cytoplasm and precisely replicates its chromosomal DNA |
| Most of the cell cycle is spent in what stage? | Interphase, or growing stage about 90% of the time |
| The time when a cell's metabolic activity is very high and the cell performs its various functions with the organism. | Interphase, or growing stage |
| Interphase can be divided into three sub phases. | G1 phase (First gap), S phase, G2 phase (second gap) |
| What happens in all three sub phases of the interphase stage | The cell grows. |
| Chromosomes duplicate in which sub phase? | S phase |
| The S in S phase stands for what? | Synthesis of DNA, or DNA replication |
| Mitotic phase | M phase, The part of the cell cycle when the cell actually divides. Accounts for 10% of the total time required for the cell cycle. |
| What phase is divided into two overlapping stages? What are the stages? | Mitotic phase. Mitosis and Cytokinesis |
| In mitosis, the nucleus and its contents divide and are evenly distributed forming | two daughter nuclei |
| Cytokinesis | Begins before mitosis ends, the cytoplasm is divided into two. Occurs along with Telophase. |
| The five stages of mitosis | Prophase, prometaphase, metaphase, anaphase, telophase |
| Prophase | Within the nucleus, chromatin fibers become tightly coiled and folded. Cytoplasm, the mitotic spindle begins to form as microtubules rapidly grow out from the centrosomes, they begin to move away from each other |
| Prometaphase | The nuclear envelope breaks into fragments and disappears. Microtubules are now highly condensed. Centromere region, each sister chromatid have protein structure called a kinetochores. |
| Metaphase | The mitotic spindle is fully formed, poles at opposite ends. Chromosomes convene on the metaphase plate, an imaginary plane equidistant between the two poles of the spindle. |
| Anaphase | Begins when the two centromeres of each chromosome come apart, separating the sister chomatids. Chromatids consider full fledged daughter chromosome. |
| Telophase | The cell elongation that started in the anaphase continues. Daughter nuclei appear at the two poles of the cell as nuclear envelopes from around the chromosomes. The reverse of prophase |
| Mitotic Spindle | A football-shaped structure of microtubules that guides the separation of the two sets of daughter chromosomes |
| The spindle microtubules emerge from two | Centrosomes |
| Centrosomes | Clouds of cytoplasmic material that in animal cells contain pairs of centrioles. (Microtubule-organizing centers) |
| In animal cells, cytokinesis occurs by a process known as | Cleavage |
| The first sign of cleavage is the appearance of | Cleavage furrow |
| Cleavage furrow | a shallow indentation in the cell surface |
| These proteins responsible of muscle contraction are | Actin and Myosin |
| Cell plate | During telophase, in plant cells, membranous vehicles containing cell wall material collect at the middle of the parent cell. The vesicles fuse forming a membranous disk. |
| The cell plate grows | The cell plate grows Outward |
| What factors affect cell division? | Anchorage, cell density, and chemical growth |
| Cells in the human liver do not divide unless the liver is | Damaged |
| Growth factor | A protein secreted by certain body cell that stimulates other cells to divide |
| Researchers have discovered how many different types of growth factors that can trigger cell division? | 50 |
| Platelet-derived growth factor | This protein promotes the rapid growth of connective tissue cells that help seal the wound |
| Vascular endothelial growth factor (VEGF) | Stimulates the growth of new blood vessels during fetal development and after injury |
| Density-dependent inhibition | A phenomenon in which crowded cells stop dividing. |
| Most animal cells exhibit _____ _____; they must be in contact with a solid surface. Ex inside of a culture dish or the extracellular matrix of a tissue to divide. | Anchorage Dependence |
| In a living animal, most cells are anchored in a _____ position. | Fixed |
| The Cell Cycle Control System | A cyclically operating set of molecules in the cell that both triggers and coordinates key events in the cell cycle. |
| At which one of the three checkpoints do the chromosomes exist as duplicated sister chromatids? | G2 and M checkpoints |
| Tumor | an abnormally growing mass of body cells |
| Benign Tumor | A lump of abnormal cells that remain at the original site. Can be removed by surgery. |
| Malignant Tumor | Can spread into neighboring tissues and other parts of the body, displacing normal tissue and interrupting organ function as it goes |
| An individual with a malignant tumor is said to have | Cancer |
| Metastasis | The spread of cancer cells beyond their original site |
| How are cancers named? | According to the organ or tissue in which they originate. |
| Based on site of origin, cancers are grouped into four categories. | Carcinomas, Sarcomas, Leukemias, and Lymphomas |
| Carcinomas | Cancers that originate in the external or internal coverings of the body (skin, lining of the intestine) |
| Sarcomas | arise in tissues that support the body (bone, muscle) |
| Leukemias and Lymphomas | Cancers of blood-forming tissues (bone marrow, spleen, lymph nodes |
| Hydra | A tiny multicellular animal that reproduces by either sexual or asexual means |
| How are chromosomes matched? | In homologous pairs |
| Somatic cell | In humans, a typical body cell that has 46 chromosomes |
| A human in what phase contains 23 sets of duplicated chromosomes. | Metaphase |
| In metaphase of mitosis, each chromosome contains how many chromatids? | 2 sister chromatids |
| A human cell at metaphase contains how many sets of duplicated chromosomes? | 23, they occur in matched pairs |
| Homologous Chromosomes | Chromosomes that have twins resembling its length and centromere position. Two chromosomes of matching pairs both carrying genes controlling the same inherited characteristics. |
| Locus | (plural- loci) A particular place on the chromosome |
| What type of chromosome pairs have different versions of the same gene? | Homologous |
| Sex Chromosomes | Determines an individual's sex |
| Autosomes | The 22 remaining pairs of chromosomes found in males and females. |
| What gender has fully homologous chromosomes? | Females (XX) |
| Life cycle | The sequence of stages leading from the adults of one generation to the adults of the next. |
| Diploid | Humans, animals, many plants are considered this because all body cells contain pairs of homologous chromosomes. |
| The total number of chromosomes is called | The diploid number (2n) |
| For humans the diploid number is | 46, 2n=46 |
| Gametes | The sperm and egg cells |
| Each _____ has a single set of chromosomes, 22 autosomes plus a sex chromosome. (X or Y | Gamete |
| Haploid | A cell with a single chromosome set; has only one member of each homologous pair. |
| The haploid number for humans is | 23, n=23 |
| _____ are made by a special sort of cell division called _____, which occurs only in reproductive organs. | Gametes, Meiosis |
| _____ produce daughter cells with the same number of chromosomes as the parent cells, _____ reduces the chromosome number by half. | Mitosis, meiosis. |
| _____ reduces the chromosome number from diploid to haploid. | Meiosis |
| _____ prevents each generation from having twice as much genetic material as the generation before | Meiosis |
| All events unique to meiosis happens in | Meiosis I |
| Tetrads | Sets of four chromatids, with each pair of sister chromatids joined at the centromeres |
| Duplicated homologous chromosomes pair to form tetrads in what phase? | Prophase I |
| Tetrads are aligned at the metaphase plate in what phase? | Metaphase I |
| Pairs of homologous chromosomes separate, sister chromatids of each chromosome stay together in what phase? | Anaphase I |
| At the end of meiosis I, There are _____ cells, with each chromosome still having two _____ _____. | Two, sister chromatids |
| Meiosis II is virtually identical to _____ because the separate sister chromatids | Mitosis |
| Each daughter cell produced by meiosis II has only one ______ set of chromosomes. | Haploid |
| All the chromosome pairs orient independently at what phase? | Metaphase I |
| Chromosomes X and Y behave as a homologous pair in | Meiosis |
| The total number of combinations of chromosomes that meiosis can package into gametes for any species is | 2^n, n=haploid number |
| Crossing over | An exchange of corresponding segments between nonsister chromatids of homologous chromosomes |
| Chiasma | (greek for cross) The sites of crossing over appear as X-shaped regions. A place where two homologous (non sister) chromatids are attached to each other. |
| Crossing over begins very early in what phase of meiosis? | Prophase I |
| Genetic Recombinant | The production of gene combinations different from those carried by the original parental chromosomes. |
| In meiosis, how many crossover events occur per chromosome pair? | one to three |
| Three sources of genetic variability in sexually reproducing organisms | Independent orientation of chromosomes at metaphase I, random fertilization, and crossing over during prophase I or meiosis. |
| Whats ultimately responsible for genetic diversity in living organisms? | Mutations |
| Karyotype | A photographic inventory of an individual's chromosomes arranged in pairs. Shows them condensed and doubled as appeared in metaphase of mitosis |
| What type of blood cell is used to prepare a karyotype? | Lymphocytes |
| Trisomy 21 | The basis of Down syndrome |
| Nondisjunction | An occasional mishap in which the members of a chromosome pair fail to separate. |
| Alterations of chromosome structure can cause | Birth defects and cancer |
| If a fragment of a chromosome is lost or removed, the remaining chromosome will then have a ______. | Deletion |
| If a fragment from one chromosome joins to a sister chromatid or homologous chromosome, it will produce a ______ | Duplication |
| If a fragment reattaches to the original chromosome but in the reverse orientation. | Inversion |
| Translocation | The attachment of a chromosomal fragment to a non homologous chromosome. May be reciprocal: two non homologous chromosomes may exchange segments |
| With the exception of identical twins, siblings who have the same two biological parents are likely to look similar, but not identical, to each other because they have | a similar but not identical combination of genes. |
| Strictly speaking, the phrase "like begets like" refers to | asexual reproduction only |
| Within one chromosome, what is the relationship between the sequence of bases in DNA of one sister chromatid compared to the other? | The sequences are identical. |
| When animal cells are grown in a petri dish, they typically stop dividing once they have formed a single, unbroken layer on the bottom of the dish. This arrest of division is an example of | density-dependent inhibition. |
| f a chromosome fragment breaks off and then reattaches to the original chromosome, but in the reverse direction, the resulting chromosomal abnormality is called a(n) | Inversion |
| Which of the following statements regarding genetic diversity is false? | Genetic diversity is enhanced by mitosis. |
| Which of the following statements regarding the differences between mitosis and meiosis is false? | Crossing over is a phenomenon that creates genetic diversity during mitosis. |
| Which of the following statements regarding prokaryotes is false? | Prokaryotic chromosomes are more complex than those of eukaryotes |
| Homologous chromosomes migrate to opposite poles during _____. | Anaphase I |
| During _____ chromosomes align single file along the equator of a haploid cell. | Metaphase II |
| At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids. | Telophase I |
| During _____ a spindle forms in a haploid cell. | prophase I |
| What are the three major checkpoints in a cell cycle? | G1, G2, M |
| When does the abnormal behavior of a cancer cell begin? | When a normal cell is converted into a cancer cell |
| When the cell cycle operates normally, mitosis produces genetically identical cells for | growth, replacement of damaged and lost cells, and asexual reproduction. |
| Because in meiosis, one duplication of chromosomes is followed by two divisions, each of the four daughter cells produced | has a haploid set of chromosomes and are not genetically identical |
| Nonsister chromatids exchange genetic material in a process | Crossing over |
| Homologous chromosomes come together as pairs in a process | Synapsis, In prophase I |
| Tetrads align at the cell equator in which phase? | Metaphase I |
| there is no chromosome duplication between the end of meiosis I and the beginning of meiosis II. T/F? | True |
| Genetic variation in gametes results from | Genetic variation in gametes results from Independent orientation at metaphase I and random fertilization. |
| The site of attachment and crossing over. | Chiasma, Nonsister chromosomes join here |
| The sources of genetic variability therefore include | Crossing over, Independent orientation of chromosomes, and Random fertilization |
| Karyotypes | are often produced from dividing cells arrested at metaphase of mitosis |
| Nondisjunction can happen if | meiosis I, if both members of a homologous pair go to one pole or meiosis II if both sister chromatids go to one pole. |
| Klinefelter syndrome | Denoted as XXY, Have a extra X chromosome, Individuals are males, but testes are abnormally small and individuals are sterile. Often includes breast enlargement, and other female body characteristics |
| Turner syndrome | Turner syndrome Denoted as XO, Lacking one X chromosome, Are females and sterile because their sex organs are underdeveloped. Individuals usually have a short statue and a web of skin between the neck and shoulders |
| XXX | Most are normal females with an extra X chromosome |
| XYY | Most are normal males with an extra Y chromosome |
| Chronic myelogenous leukemia (CML) | is one of the most common leukemias,affects cells that give rise to white blood cells (leukocytes), and results from part of chromosome 22 switching places with a small fragment from a tip of chromosome 9. |
Created by:
Razorbacks