Cyclins
are the chemicals that regulate the cell cycle. Cyclins work by regulating the timing
of the cell cycle in eukaryotic cell. Cyclins activates cyclin dependent
kinases (CDKs) (an enzyme that works by adding <span>negatively charged phosphate groups to other
molecules in a process called phosphorylation) by binding to it to form a cyclin-Cdk
complex. This complex then functions by acting as a signal to the cell to move
to the next cell cycle phase. At the end of the event, the cyclin is degraded, Cdk
is deactivated, therefore signaling exit from a specific phase.</span>
I think the answer is C) Knots are related to the global coordinate system.
<span>The
mitochondria are famously known as the powerhouse of the cell since it is the
one that gives the cells energy that is also used by the human being. This energy conversion is called oxidative
phosphorylation. Mitochondria are found in eukaryotic cells, including
humans. These organelles also had its
own genome, or what we called as DNA which is known as mitochondrial DNA, or
mtDNA which is present in the mitochondrial matrix. The role of mtDNA or mitochondrial DNA is to
convert the energy from food into any other forms that it thinks the cell can
use. It is containing 37 genes which are
all necessary for a normal mitochondrial function.</span>
These statements are both true. However, tuna are warm blooded and all other fish (but mackerel shark) are cold blooded. There are many fish that swim in both the Atlantic and Mediterranean. Therefore the answer must be B.