Explanation:
Methods of Solid Waste Disposal and Management:
Solid Waste Open Burning.
Sea dumping process.
Solid wastes sanitary landfills.
Incineration method.
Composting process.
Disposal by Ploughing into the fields.
Disposal by hog feeding.
Salvaging procedure.
Plants inherit genes that enable them to produce chlorophyll, but this pigment is not produced unless the plants are exposed to light. this is an example of how the environment can influence on gene expression.
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Light has an important role in gene expression in plants by producing a number of light-induced changes. One of the examples of the light effects is that chlorophyll and the proteins required for assembling the photosynthetic apparatus are synthesized together with the enzymes needed for carbon fixation. Gene expression influenced by light includes the regulation at the level of transcription or, alternatively regulation of translation.</span>
Answer:
Introduction In ecology and biology, abiotic components are non-living chemical and physical factors in the environment which affect ecosystems. Biotic describes a living component of an ecosystem; for example organisms, such as plants and animals. Examples Water, light, wind, soil, humidity, minerals, gases.
Explanation:
Answer:
Amniocentesis is an invasive method that involves the aspiration of 10-20 ml of fetal water through the abdominal wall under ultrasound-guided control. In most cases, the procedure is performed around the 16th week of gestation. The fetal water sample contains fetal cells, mostly cells of fetal skin and the epithelium of the urinary tract.
Chorionic Villus Sampling (CVS) biopsy is performed between weeks 11 and 12 of gestation. During biopsy, with ultrasound guidance, the tissue of the chorionic fossa is aspirated mainly across the abdomen (transabdominal pathway). The biopsy specimen is of fetal origin and belongs to the outer layer of blastocyst cells or the trophoblast (outer layer of the placenta). Very often, the biopsy specimen contains tissue of the decidua (mucous membrane of the uterus) that is of maternal origin, and it is necessary to remove the maternal tissue before any treatment of the sample.
Explanation:
The amniocentesis procedure carries a risk of miscarriage of 0.5-1%. After aspiration of the fruit of the water, the sample is centrifuged to separate the cells from the amniotic fluid. Separate cells are seeded on a nutrient medium (cell culture) that stimulates cell growth. After about 14 days, the cell culture is further used for various genetic or biochemical analyzes such as karyotyping.
The advantage of chorionic biopsy is the amount of biological material, which is sufficient for the whole a number of different laboratory procedures. Also, a great advantage is the timing of the procedure as it allows diagnosis in the first trimester of pregnancy, but the chorionic biopsy procedure itself carries a risk of miscarriage of 1-2%.
Answer:
Cells vary greatly in shape These shapes are often related to the function they perform. like the disk shape of erythrocytes can absorb and transport oxygen due to increased surface area., the amoeboid shape of leukocytes allow them to squeeze through capillaries. etc.
Explanation:
Cells can be disc-like , polygonal, rectangular, cubopid thread like branched or even irregular. these are related to the functions that each cell performs.
Some examples showing relation between cell shape and function are as follows.:
- Human blood cells are circular and biconcave to transport oxygen.
- White blood cell are amoeboid to squeeze through thin capillaries.
- Nerve cells are long so that they can carry nerve impulse to a long distance very quickly.
- Guard cells of stomata are bean or dumbell shaped to open and close the stomata.
