when you observe heart cells of a 16 year old boy under a microscope in which stage of cell division do you find them? what is the significance of the stage. DON'T SPAM IF YOU SPAM THEN YOUR ACCOUNT WILL BE REPORTED AND BLOCKED.
Answers
Explanation:
Cell Reproduction and Conception
Most human cells are frequently reproduced and replaced during the life of an individual. However, the process varies with the kind of cell. Somatic click this icon to hear the preceding term pronounced, or body cells, such as those that make up skin, hair, and muscle, are duplicated by mitosis click this icon to hear the preceding term pronounced. The sex cells, sperm and ova, are produced by meiosis click this icon to hear the preceding term pronounced in special tissues of male testes and female ovaries click this icon to hear the preceding term pronounced. Since the vast majority of our cells are somatic, mitosis is the most common form of cell replication.
Mitosis
The cell division process that produces new cells for growth, repair, and the general replacement of older cells is called mitosis. In this process, a somatic cell divides into two complete new cells that are identical to the original one. Human somatic cells go through the 6 phases of mitosis in 1/2 to 1 1/2 hours, depending on the kind of tissue being duplicated.
drawings of the 6 phases of mitosis
Six phases of mitosis
mitosis close up
click this icon in order to see the following video Mitosis--video clip from Teachers' Domain
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Some human somatic cells are frequently replaced by new ones and other cells are rarely duplicated. Hair, skin, fingernails, taste buds, and the stomach's protective lining are replaced constantly and at a rapid rate throughout our lives. In contrast, brain and nerve cells in the central nervous system are rarely produced after we are a few months old. Subsequently, if they are destroyed later, the loss is usually permanent, as in the case of paraplegics. Liver cells usually do not reproduce after an individual has finished growing and are not replaced except when there is an injury. Red blood cells are also somewhat of an exception. While they are being constantly produced in our bone marrow, the specialized cells from which they come do not have nuclei nor do the red blood cells themselves.
Meiosis
Meiosis is a somewhat similar but more complex process than mitosis. This is especially true in females. While mitosis produces 2 daughter cells from each parent cell, meiosis results in 4 sex cells, or gametes click this icon to hear the preceding term pronounced in males and 1 in females. Unlike the cells created by mitosis, gametes are not identical to the parent cells. In males, meiosis is referred to as spermatogenesis click this icon to hear the preceding term pronounced because sperm cells are produced. In females, it is called oögenesis click this icon to hear the preceding term pronounced because ova, or eggs, are the main ultimate product. The illustration below shows the 8 phases of spermatogenesis.
Answer:
The cells of the heart , cardiac tissue are uninucleated and branced. Branches are united by intercalated disc.
Quiescent stage in cell division.
Some cells in adult animals do not appear to exhibit division [e,g. heart cells] and many other cells divide only occasionally as needed to replace cells that have been lost because of injury or cell death.
The cells that do not divide further exit G 1 phase to enter an inactive stage called quiescent stage. (G
0 ) of the cell cycle.