The embryonic endoderm<span> develops into the interior linings of two tubes in the body, the digestive and respiratory tube. the </span>lining<span> of the follicles of the thyroid gland and the</span>epithelial<span> component of the thymus (i.e. thymic </span>epithelial<span> cells). Liver and pancreas cells are believed to </span>derive<span> from a common precursor.</span>
Explanation:
Variations in the sun's energy reaching Earth
Changes in the reflectivity of Earth’s atmosphere and surface
Changes in the greenhouse effect, which affects the amount of heat retained by Earth’s atmosphere
Answer:
Bone.
Explanation:
Calcium is one of the important element present in the body. Calcium plays an important role in the muscle contraction. The calcium ions also acts as a signalling molecule during cell signalling.
The calcium is present in our extracellular fluids, bones, and teeth. The major constituent of calcium is present in the bone. The bone consists of around 90% body;s calcium.
Thus, the correct answer is option (b).
Answer:
Mitochondrial proteins enter the organelle through channels formed by membrane proteins present in its inner and outer membranes.
Explanation:
All the biological membranes have lipid bilayer with the non-polar core that does not allow entry of charged and large substances. Mitochondrial proteins are synthesized in the cytosol and the unfolded proteins bind to the chaperons that deliver them to the receptors present in the outer mitochondrial membrane.
The receptor moves the protein to the membrane channels formed by integral membrane proteins of inner and outer mitochondrial membranes. The proteins enter the intermembrane space and are targeted to the inner membrane through channels while chaperons are left outside only.
4. nucleoid region
Bacterial cell's do not have a nucleus; their DNA is found in this region.
