The answer is B. a nucleus.
Prokaryotic cells do not have a nucleus. They have ribosomes, a cell membrane, a cell wall, and DNA, but lack a nucleus. Prokaryotes also don't have mitochondria or chloroplasts and generally lack organelles.
Answer:
Hormones act as first messenger but not as second messengers.
Explanation:
Second messenger act as signaling molecule which are secreted in response to various biological signals generated by first messenger such as hormones,neurotransmitters etc.Second messengers include various bioactive molecules such as cyclic AMP(cAMP),cyclic GMP(cGMP),inositol triphosphate(IP3),diacylglycerol(DAG),calcium ions(Ca2+) etc.
Hormones are extracellular signaling molecules whereas second messengers are intracellular signaling molecules.
C. Dependent variable
The independent variable is what you want to change (ex amount of light given to plants)
The dependent variable is what changes because of the independent variable (ex the height of the plants)
So Independent is what you change, Dependent is what you measure
Answer:
six
Explanation:
Professor of Chemistry, University of Minnesota, Minneapolis. Oxygen group element, also called chalcogen, any of the six chemical elements making up Group 16 (VIa) of the periodic classification—namely, oxygen (O), sulfur (S), selenium (Se), tellurium (Te), polonium (Po), and livermorium (Lv).
Answer:
Thalidomide may be defined as a type of the sedative drug that in the earlier time referred for the pregnant ladies. This drug causes the world wide tragedy and acts as a teratogen.
This drug causes mutation in the fetus. The Ames test is effective to understand the mutagenicity of the drug. In this test, if the auxotrophic strain of the bacteria is grown on the the deficient media containing thalidomide drug. The bacteria growth indicates the positive Ames test and the substance is considered as mutagen.
