Answer:
The nektonic organisms are those marine organisms that are found in almost every depth. These can move freely from one place to another in the ocean body due to its ability to swim. For example, Turtles, sharks, Fishes, and dolphins.
The planktonic organisms are passive swimmers, as they can move along with the ocean currents and are mostly found in the upper portion of the ocean body. For example, Diatoms and Rotifers.
The benthos is the bottom-dwelling organisms that cannot swim. For example, Bivalves, Corals and Sponges.
The nektonic organisms are different from the planktons and the benthos because the nektons can easily swim. They are constructed with such body parts that allow them to swim and migrate from one region to another region within the ocean water body. Whereas the planktons and the benthos cannot migrate easily and are considered as sessile organisms.
Answer:
a. heart development.
Explanation:
As the third week of fetal development starts, the process of formation of blood vessels begins. Also, the splanchnic mesoderm in the head end of the embryo forms heart on days 18 and 19. Since it develops heart, this part of the mesodermal cells is called the cardiogenic area. The underlying endoderm sends the induction signals to these mesodermal cells to form a pair of endocardial tubes that gradually develop into a single primitive heart tube.
This primitive heart begins to beat by the end of the third week of development. Therefore, any drug that affects fetal development during the first 20 days of the pregnancy might affect the development of the heart.
Answer:
As a general rule, if you're in the Northern Hemisphere, look towards the southern skies to see the galactic core. This can be southeast (Spring), due south (Summer), or southwest (Fall) depending on the time of year. As mentioned above, Sagittarius is found nearest the galactic core.
Explanation:
Answer:
Microarray technology is a very useful technology that allows to study the measure the expression levels of large numbers of genes simultaneously. It consists of a solid support (that can be glass, silice, or nylon), and to it are attached a lot of single stranded DNA fragments that acts like probes. By complementarity, the genes corresponding to this probes that are being expressed at some time will attach to it. Probe-target hybridization is usually detected and quantified by detection of a fluorophore compund, a silver stained, or chemiluminescence-labeled targets.
I would say carbon dioxide