The hypothalamus in the brain contributes to the body's maintenance of a steady internal physiological state, called homeostasis.
Answer: zooplankton, small nekton
Explanation:
The scientists rely on the following cues to hypothesise and test for the presence of life on various extraterrestrial bodies:
1. Presence of water
2. Presence of hydrocarbons
3. Presence of carbon
4. Presence of salt pans
The presence of hydrocarbons may indicate that there's anaerobic life thriving beneath the surface of the meteorite. The presence of traces of carbon may indicate that there was life once thriving on its surface ( which however is not possible in case of a meteorite because of its size). The absence of any of the above listed items will indicate that the surface of the meteorite is devoid of any life.
Answer:
a mutation that blocks the GTPase activity of Ras
Explanation:
A G protein in inactive state is GDP bound but as soon as a guanine exchange factor (GEF) exchanges it with GTP it gets activated which means that in GTP bound state it is active. G - protein has endogenous GTPase activity. Upon interaction of GAP, the GTPase activity of this protein is exhibited. When GAP is present, hydrolysis of GTP into GDP occurs which leads to inactivation of G protein. A mutation which will block GTPase activity of Ras will therefore result in constitutive active signaling even in the absence of ligand binding to it's receptor. In such scenario, GTP will not be hydrolyzed into GDP so signaling will be up-regulated.
