Answer:
No, viruses are not considered cells as they're parasitic and can't live on their own. A virus has to infect living cells in order to survive, so it's not considered a cell.
Answer:
1. Chromatin condense into chromosomes.
4. Homologous chromosomes pair up (formation of tetrads).
5. Homologous chromosomes separate and move to poles.
2. Sister chromatids separate.
3. Chromosomes unravel in to chromatin.
Explanation:
This question portrays the process of meiosis in a cell. The ordered sequence of events in the options are:
1. Chromatin condense into chromosomes - This process occurs in the Prophase stage. Prior to the cell division, the nuclear material is found as Chromatin material. This Chromatin material then undergoes condensation to form visible chromosomes.
4. Homologous chromosomes pair up (formation of tetrads) - This process also occurs during the Prophase stage of meiosis I. In this stage, homologous chromosomes (similar but non-identical chromosomes received from each parent) are paired up side by side to form a structure known as TETRAD or BIVALENT.
5. Homologous chromosomes separate and move to poles - This process characterizes the Anaphase stage of meiosis I. Homologous chromosomes are pulled apart to opposite poles of the cell by spindle microtubules.
2. Sister chromatids separate - After meiosis I, meiosis II involving sister chromatids instead of homologous chromosomes follows. In the Anaphase stage of meiosis II specifically, sister chromatids are pulled apart towards opposite poles of the cell.
3. Chromosomes unravel in to chromatin - After the whole division process i.e. karyokinesis (division of the nuclear material), the chromosomes begin to unravel to form the CHROMATIN threads once again. This process occurs in the Telophase stage of meiosis.
<span>B.The existence of vestigial structures
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Vestigial structures have been used for long by evolutionists to support the theory of evolution. These organs are believed to have been in use in the past lives but as the species adapts to new forms of life and lifestyle,the vestige organs becomes obsolete,but are not removed by the body. An example of vestige organs in human being are the appendix,tail bone,and mammalian grands in men.
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Answer:
The answers to the blank spaces are numbered as follows:
1. Function
2. Nucleus
3. Mitochondria
4. ATP
5. Chloroplast
6. Glucose
7. Ribosomes
Explanation:
This question is describing the organelles found in a cell. An organelle is a structure that performs a specific FUNCTION (1) in a cell. There are different kinds of organelles with each possessing its own peculiar function. Some of them are as follows:
- NUCLEUS, which is regarded as the brain of a cell because it directs or controls a cell's activities just like the brain of an organism does.
- MITOCHONDRIA is an organelle that produces the energy storing compound called ATP (adenosine triphosphate), hence, it is called power house of the cell.
- CHLOROPLAST is an organelle found in plant cells that functions in the conversion of light energy (from sun) into GLUCOSE (chemical energy) in a process called PHOTOSYNTHESIS.
- RIBOSOMES is an organelle found in both prokaryotic and eukaryotic cells that serves as the site of PROTEIN production in a cell.
