The answer is D, Because dinosaurs appears in the Triassic period while insects appeared in the Devonian period which is about 160 million years about, which rules out A and B. Humans have been on Earth for almost 3 million years, which is nothing compared to the history of life in earth, which about 4,000 million years of life history, so D
Answer:
(1) Nitrite poisoning
(2) Its cause is elevated levels of nitrite in the pond or culture system water.
A bacteria cell differs from a plant or animal cell by being less complex in structure.
Testosterone is an example of a steroid. Its physiological functions include:
1. Determines the the gender of a developing embryo.
2. Development of reproductive organs and the prostrate gland in males.
3. Responsible for secondary sexual characteristics in males such as deeper pitch, increased muscle bulk, hair on the upper lip.
4. Regulates normal sperm development.
Another steroid is cholesterol. Physiological functions include:
1. Helps maintain the structure of cells and vessels improving overall health and function in the body.
2. Precursor to important sex hormones such as testosterone and estrogen.
3. Used as an insulator around nerves and is absolutely essential for brain function.
4. Precursor to Vitamin D, which supports a healthy immune and nervous system
Rate of growth of a seedling over two weeks
