The mantle is the layer of the Earth that makes up most of Earth's mass. The mantle is a thick layer of hot rock that surrounds the hot, liquid, outer core. The mantle is below the crust and above the outer core.
The function of the ovaries and testicles is to form the sexual gametes for the formation of a new being (zygote, embryo). So probably the correct answer is the C
The correct answer is: d) intercalated discs
Cardiac muscle tissue is muscle tissue found in the heart. It is similar to skeletal muscle in that both are striated and organized into sarcomeres but cardiac muscle fibers are shorter and usually contain only one nucleus in the central region of the myocyte (muscle cell). Cardiac muscle fibers are rich in mitochondria and myoglobin, (ATP is produced primarily through aerobic metabolism), are extensively branched and are connected to one another by intercalated discs. An intercalated disc is a structure that enables the propagation of contraction among muscle cells: it allows the muscle cells to contract in a wave-like pattern.
Answer:
The UN projects that the global population increases from a population of 7.7 billion in 2019 to 10.9 billion by the end of the century. By that time, the UN projects, fast global population growth will come to an end.
Beneath the global level, there are of course, big differences between different world regions and countries. While in some regions the world population will likely grow rapidly for the coming decades other regions will continue to see declining population numbers.
Global population growth is determined by the number of births and deaths. Improving health is increasing the size of the population as it is decreasing mortality. The countervailing trend are falling fertility rates – the trend of couples having fewer children is what brought rapid population growth to an end in many countries already, and what will bring an end to rapid population growth globally.
The global population growth rate has already slowed down considerably: It reached its peak at over 2% in the late 1960s and has been falling since.
The UN projections for the global population growth rates, which have been produced since the 1950s, have a good track record in projecting the size of the global population.
While the UN projections are most widely know there are other very carefully produced projections. The demographers of WC-IIASA model what will happen according to different scenarios and make clear that the population growth rate tomorrow depends on what we do today. Rapid progress in getting children and especially girls into schools will result in a much smaller global population.
The biggest disagreement between different projections is concerning the future of Africa. While the UN projects a 3.5-fold increase of the population of Africa, other researchers find a much smaller increase more likely.
Explanation:
here try this
<>"A further increase in the size of a cell could result in a surface area too small for adequate exchange of materials. Google: A large surface to volume ratio means that a small amount of living matter has a large surface through which nutrients, oxygen and wastes can diffuse."<>
