"<span>The central vacuole is a cellular organelle found in plant cells. It is often the largest organelle in the cell. It is surrounded by a membrane and functions to hold materials and wastes. It also functions to maintain the proper pressure within the plant cells to provide structure and support for the growing plant."</span>
Answer:
A - Chloroplast (although the arrow looks like it is pointed at the Thylakoid membrane)
B - Vacuole
C - Cell wall
D - Smooth Endoplasmic Reticulum (top) and Rough Endoplasmic Reticulum (down below)
Explanation:
The hormone<span> oxytocin is a positive feedback mechanism that enhances labor contractions. </span>
The answer is RNA polymerase binds to a promoter region of DNA.
A promoter region of DNA is the site of initiation of gene transcription. For transcription to start, firstly, RNA polymerase must bind to a promoter region of DNA. RNA polymerase is an enzyme responsible for a synthesis of RNA and it enables nucleotides to covalently link together. When RNA polymerase reaches a terminator region, premature RNA frees. Further, <span>introns are edited out of the premature RNA, and mature RNA is synthesised.</span>
<span>The plasma membrane or the cell
membrane is the one that protects the cytoplasm of a cell. It is mostly
composed of lipids and proteins. It has a phospholipid bilayer that controls
the entering and exiting of molecules in the cell and at the same time,
provides protection for the cell or plasma membrane. Proteins embedded within
the phospholipid bilayer have the same function of the plasma membrane that
includes selective transport. The phospholipid bilayer consists mainly of the
lipid molecules. The answer is letter B. </span>