Answer:
evolution of life on Earth
Explanation:
Life began on Earth at least 3.5 to 4 billion years ago, and it has been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later, the first multicellular organisms evolved, and after that, Earth's biodiversity greatly increased.
The bell shaped curve indicates polygenic traits. A polygenic trait is controlled by multiple alleles. Hope this makes sense :)
Answer:
Molecules stop moving at freezing point. Helium has the lowest boiling point. The molecules move very quickly at boiling point.
Explanation:
Heating up- molecules move faster. Cooling down- molecules move slower
Answer:
Linings of hollow organs
Explanation:
Smooth muscle cells are usually found in the lining of hollow organs such as all arteries and veins, wall of stomach, uterus, urinary bladder, digestive system etc. The cells of these linings are spindle shaped and consist of a nucleus at the center which lacks striations.
They work as a housekeeper and are under involuntary control except the heart. They lack striation because of irregular arraying of actin and myosin filament along the length of the cell.