Biology helping with medical research and treatment
The eukaryotic kingdom known known as Chromista is composed of single celled organisms among which of all the algae containing chlorophyll a and c. Most of the species belonging to this group are also photosynthetic.
Due to the vast number of species, some Chromistas have an asexual reproduction, whereas other reproduce sexually.
Asexual reproduction is achieved by the process of cellular division known as mitosis in which a parent cell divides into two identical daughter cells.
Sexual reproduction occurs through flagellated zoospores. Male gamets are produced by the antheridia, the male sex organ of algae, ferns, fungi etc. The haploid female gamets are produced through mitosis in oogonia. The joining of two gamets is called syngamy.
Answer:
Explanation:
A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a plane where many earthquakes occur, called the Wadati–Benioff zone.[1] These collisions happen on scales of millions to tens of millions of years and can lead to volcanism, earthquakes, orogenesis, destruction of lithosphere, and deformation. Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere. The geologic features related to convergent boundaries vary depending on crust types.
Plate tectonics is driven by convection cells in the mantle. Convection cells are the result of heat generated by radioactive decay of elements in the mantle escaping to the surface and the return of cool materials from the surface to the mantle.[2] These convection cells bring hot mantle material to the surface along spreading centers creating new crust. As this new crust is pushed away from the spreading center by the formation of newer crust, it cools, thins, and becomes denser. Subduction begins when this dense crust converges with less dense crust. The force of gravity helps drive the subducting slab into the mantle.[3] As the relatively cool subducting slab sinks deeper into the mantle, it is heated, causing hydrous minerals to break down. This releases water into the hotter asthenosphere, which leads to partial melting of asthenosphere and volcanism. Both dehydration and partial melting occurs along the 1,000 °C (1,830 °F) isotherm, generally at depths of 65 to 130 km (40 to 81 mi).[4][5]
Some lithospheric plates consist of both continental and oceanic lithosphere. In some instances, initial convergence with another plate will destroy oceanic lithosphere, leading to convergence of two continental plates. Neither continental plate will subduct. It is likely that the plate may break along the boundary of continental and oceanic crust. Seismic tomography reveals pieces of lithosphere that have broken off during convergence
ANSWER: Trapped in a ship's ballast or water tank.
REASONING: There are many examples of species being transported in the ballast or water tank of ships. Ships need to be stable so they don't turn over. Stability is provided by weight in the bottom part of the ship called the ballast. This weight often comes from water that is stored in water tanks or the ballast area of the ship. Water is taken in to the ballast at the beginning of its voyage. When it arrives at it's destination, the ballast water is often drained. Anything living in that water will also be drained in to the new location. This is how species like the white perch can be introduced into new areas.
