Given that an average human has a heart rate of 70 beats per minute and if one is to have a 70 year life span, the number of times it will beat is 2,575,440,000 times. This was computed by multiply 70 years by 365 days/year x 24 hours/day x 60 minutes/hour x 70 beats/min. Thus, the heart will beat numerous times before it finally stops.
Coal, oil and natural gas carbon dioxide (CO2)
Answer:
After constructing a prototype of the device, the student concludes that in many regions the monetary cost of building and installing the device would be higher than the cost of acquiring water from other sources. Which of the following would be most appropriate for the student to do next?
redesign the device without the solar panel so that it plugs into an electrical outlet
Explanation:
Because of cost implication, the device is redesigned in order to use other source rather than water which would be cost-effective and generally accepted for use.
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: Question 1 answer: Skin cells continually replicate
Explanation: The cells in the superficial or upper layers of skin, known as the epidermis, are constantly replacing themselves. This process of renewal is basically exfoliation (shedding) of the epidermis. But the deeper layers of skin, called the dermis, do not go through this cellular turnover and so do not replace themselves.
Question 2 answer: Heart cells undergo terminal differentiation
Explanation: Different cell types (e.g., neurons, skeletal and heart myocytes, adipocytes, keratinocytes) undergo terminal differentiation, in which acquisition of specialized functions entails definitive withdrawal from the cell cycle.
Question 3 answer: DNA replicates in the nucleus
Explanation: DNA replication occurs in the cytoplasm of prokaryotes and in the nucleus of eukaryotes. Regardless of where DNA replication occurs, the basic process is the same. The structure of DNA lends itself easily to DNA replication.
Question 4 answer: The ability to reverse terminal differentiation might affect gene expression in a complex organism
Question 5 answer Cytoplasm replicates during mitosis
Explanation: This process involves replication of the cell's chromosomes, segregation of the copied DNA, and splitting of the parent cell's cytoplasm. ... The outcome of binary fission is two new cells that are identical to the original cell.
