I am going to go with either C,A B.
I'm not entirely sure. it's just what i think
Answer:
it is D
What global climatic change gave gymnosperms an advantage over ferns?
A) Increased fluctuations in global climate
B) the climate becoming hotter and wetter
C) the climate becoming cooler and drier
D) the climate becoming hotter and drier
The correct sequence of events is : C,D,B,A.
Iron rich magma in the earth's core heats up because of radiation and the pressure exerted by the other layers of the earth. This heat in the crust trigger convection currents in the mantle. The magma closest to the core will be hotter and therefore less dense than other layers. Being less dense the layer will rise towards the crust, eventually becoming cooler and sinking back down in a circular motion.
The continued circular motion creates electric currents which then generates the magnetic field.
In English please so I can help you with your problem
Answer:
Explanation:
Cell specialization is also called cell differentiation. Through this process, specialized cells form from the unspecialized cells. Then many cells are formed and determined to form specialized functions.
The stem cells are the unspecialized cells which form a different kind of specialized cells.
The muscle cells, nerve cells, sperm cells, red blood cells are specialized cells perform different specialized functions. All these cells arise from stem cells. The nerve cells receive impulse, muscle cells can contract, etc.
There are certain inductive signaling genes that send the signal to the differentiated cells. These signaling molecules are called ligands. These ligands move to another cell to produce specialized cells. In other words, there are some transcription factors and genes responsible for such cell differentiation and the formation of specialized cells.
Another example is zygote, which is an unspecialized cell. This is also a totipotent cell that has the potentiality to reproduce different cells.