State one process other than cell growth, which occurs during phase G2. (1) b. Account for the changes in the quantity of DNA in the cell during mitosis. (2) 2. The diagrams below represent the chromosomes during stages in the process of mitosis.
(A 1 a, B 1 b, C 1 c, D 1 d). When crossing over occurs, the chromosomes will cross and the genes will be exchanged from one chromosome to another. (A 1 a, b1 B, c 1 C, D 1 d). Crossing-over occurs during meiosis I. 15.
Mitosis is the step during which the cell’s nucleus divides into two new nuclei. During mitosis, one copy of the DNA is distributed into each of the two daughter cells. Scientists divide mitosis into four parts (phases): prophase, metaphase, anaphase, and telophase. During prophase, the thread-like chromatin in the nucleus condenses to form double-rod structures called chromosomes. During metaphase, the chromosomes line up across the center of the cell.
Cell division stops until p53 binds to DNA and repairs the damage. C. p53 is an example of an oncogene, and its expression causes uncontrolled cell division. D. activation of p53 leads to inhibition of the S-phase cyclin-CDK complex. 6. All of the following statements correctly describe M-Cdk, EXCEPT: A. M-Cdk causes the cell to enter S phase and begin DNA replication.
3. When genes for different characteristics are found on the same chromosome, they are called linked genes. Linked genes will usually be inherited together. Exceptions to this linkage occur when crossing over happens. Crossing over is a swapping of chromatid parts of homologous chromosomes early in meiosis, resulting in chromosomes with new combinations of genes and results in increased variation across resulting
Comparison chart | Meiosis | Mitosis | Definition: | A type of cellular reproduction in which the number of chromosomes are reduced by half through the separation of homologous chromosomes in a diploid cell. | A process of asexual reproductionin which the cell divides in two producing a replica, with an equal number of chromosomes in haploid cell | Function: | sexual reproduction | Cellular Reproduction & general growth and repair of the body | Type ofReproduction: | Sexual | Asexual | Occurs in: | Humans, animals, plants, fungi | all organisms | Genetically: | different | identical | Crossing Over: | Yes, mixing of chromosomes can occur. | No, crossing over cannot occur.
During prophase, the DNA forms chromosomes by coiling. During Metaphase, the chromosomes align in the middle of the cell. During Anaphase the fibers shorten and begin to split. During Telophase the spindle fibers disintegrate. It is my understanding that cancerous cells will shoe more cells in stages of mitosis than healthy cells.
Meiosis – The process by which sex cells (sperm and egg) are formed by reducing the number of chromosomes by half. 3. Asexual Reproduction – The process by which a single organism produces a new organism identical to itself; requires only ONE parent. 4. Sexual Reproduction – The process by which a new organism is formed from the joining of a sperm and egg cell; requires a MALE and FEMALE.
These sister chromatids are then separated in anaphase as the spindle microtubules attaches to centromere and pulls the sister chromatids to opposite poles. As the sister chromatids separate they are called chromosomes. This means that each pole has the same chromosomes (same genetic material). Finally the microtubules break down, the chromosomes uncoil and the nuclear membrane reforms. The cell then divides into two daughter cells with genetically identical
Errors in nucleotide sequences are called ____________________. 29. Errors in nucleotide sequencing are corrected by enzymes called ____________________ ____________________. 30. The circular DNA molecules in prokaryotes usually contain ____________________ replication forks during replication, while linear eukaryotic DNA contains many more.