Across
- 4. the first stage of cell division, before metaphase, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears. The first prophase of meiosis includes the reduction division.
- 5. a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
- 6. the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.
- 7. an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner layer being folded inward to form layers (cristae).
- 8. a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
- 10. the final phase of cell division, between anaphase and interphase, in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed.
- 11. (in green plant cells) a plastid that contains chlorophyll and in which photosynthesis takes place.
- 12. the second stage of cell division, between prophase and anaphase, during which the chromosomes become attached to the spindle fibers.
- 13. the smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane. Microscopic organisms typically consist of a single cell, which is either eukaryotic
- 15. form a protein structure that divides the genetic material in a cell. The spindle is necessary to equally divide the chromosomes in a parental cell into two daughter cells during both types of nuclear division: mitosis and meiosis. During mitosis, the spindle fibers are called the mitotic spindle.
- 16. a self-replicating material that is present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.
Down
- 1. the stage of meiotic or mitotic cell division in which the chromosomes move away from one another to opposite poles of the spindle.
- 2. the material of which the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and DNA.
- 3. each of the two threadlike strands into which a chromosome divides longitudinally during cell division. Each contains a double helix of DNA.
- 9. a point where two systems, subjects, organizations, etc. meet and interact.
- 11. the semipermeable membrane surrounding the cytoplasm of a cell.
- 13. a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.
- 14. the positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass.