The "Spanish" influenza pandemic of 1918–1919, which caused ≈50 million deaths worldwide, remains an ominous warning to public health. Many questions about its origins, its unusual epidemiologic features, and the basis of its pathogenicity remain unanswered. The public health implications of the pandemic therefore remain in doubt even as we now grapple with the feared emergence of a pandemic caused by H5N1 or other virus. However, new information about the 1918 virus is emerging, for example, sequencing of the entire genome from archival autopsy tissues. But, the viral genome alone is unlikely to provide answers to some critical questions. Understanding the 1918 pandemic and its implications for future pandemics requires careful experimentation and in-depth historical analysis.
Mitosis
Involves one cell division?
Results in two daughter cells
Results in diploid? daughter cells? (chromosome? number remains the same as parent cell)
Daughter cells are genetically identical
Occurs in all organisms except viruses
Creates all body cells (somatic?) apart from the germ cells? (eggs and sperm)
Prophase is much shorter
No recombination/crossing over occurs in prophase.
In metaphase individual chromosomes (pairs of chromatids) line up along the equator.
During anaphase the sister chromatids are separated to opposite poles.
Meiosis
Involves two successive cell divisions
Results in four daughter cells
Results in haploid? daughter cells (chromosome number is halved from the parent cell)
Daughter cells are genetically different
Occurs only in animals, plants and fungi
Creates germ cells (eggs and sperm) only
Prophase I takes much longer
Involves recombination/crossing over of chromosomes in prophase I
In metaphase I pairs of chromosomes line up along the equator.
During anaphase I the sister chromatids move together to the same pole.
During anaphase II the sister chromatids are separated to opposite poles.
Similarities
Mitosis
Diploid parent cell
Consists of interphase, prophase, metaphase, anaphase and telophase
In metaphase individual chromosomes (pairs of chromatids) line up along the equator.
During anaphase the sister chromatids are separated to opposite poles.
Ends with cytokinesis.
Meiosis
Diploid parent cell
Consists of interphase, prophase, metaphase, anaphase and telophase (but twice!)
In metaphase II individual chromosomes (pairs of chromatids) line up along the equator.
During anaphase II the sister chromatids are separated to opposite poles.
Ends with cytokinesis.
Answer: Local chemical conditions
Explanation: A Precapillary Sphincter is a smooth muscle that is located in circles around the capillaries.
The precapillary sphincter helps to coordinate blood flow to the into the capillaries by causing the capillaries to decrease the flow of blood to tissues that are dormant or not active.
Answer:
The animals of the Earth and their environment the history of life on Earth how people and animals interact and live how living organisms interact and function Biology answers many questions, but its main focus is how living organisms interact and function.
Explanation:
