The hypothalamus in the brain contributes to the body's maintenance of a steady internal physiological state, called homeostasis.
Answer:
notochord, dorsal hollow nerve cord, pharyngeal slits, and a post-an4l tail
Explanation:
had to censor second to last word but the 4 is an a
All the cells don't have all of the intracellular structures because each and every cell do not need each and every intracellular structure. The plant cells have chloroplasts because they need to convert the light energy into chemical energy via the process of photosynthesis, the animal cells, however, have no such need, therefore, the animal cells do not have chloroplasts. Also, the erythrocytes do not have the cellular organelles in them which are present in the other body cells, because there is no need for the cellular organelles in them. The large vacuoles in plant cells is also a great example. The plants need the vacuoles for the metabolic processes, while most animal cells have no need for them.
Answer:
A = Activator
B = Effector
Explanation:
An activator is a protein which typically binds to a short (50–1500 bp) region of DNA which might be located either upstream (mainly) or downstream of a gene so as to cause increased transcription. This particular region of DNA is known as enhancer and activator is also known as transcription factor. Activator is a trans-acting factor which binds to the cis-acting factor which is enhancer so as to enhance transcriptional expression.
But another protein named as effector may restrict activator from binding to the enhancer leading to a decrease in transcriptional expression by binding to the activator allosterically. Allosteric binding of effector to the activator causes conformational change in activator so it can no longer bind the enhancer.