Answer:
C
Explanation:
Keystone species is the sea otter. Sea otters, playing a critical role in containing the urchin populations, prey on urchins and thus control the numbers of kelp grazers to maintain the forest.
Remember, keystone species is most often a top level predator in an ecosystem.
Answer:
Variations are caused by mutation. random mating between organisms.
Explanation:
Answer:
The answer is insulin.
Explanation:
Pancreatic juice is an enzyme containing secretion produced by the pancreas into the small intestine. Enzymes in the pancreas help in digesting proteins, carbohydrates and fats. The constituent enzymes are as follows:
- Trypsinogen and Chymotrypsinogen: Precursors of the proteases, trypsin and chymotrypsin that digest proteins. They are released as precursors to protect the intestinal lining. Enterokinase, an enzyme secreted by small intestine's epithelial cells, activates these precursor.
- Lipase: Enzyme that digests lipids by hydrolysing triglycerides into 2-monoglyceride and two free fatty acids.
- Amylase that helps in digesting any left over carbohydrates and complex starch.
Insulin:
Insulin can never be part of pancreatic juice because it is a hormone, not an enzyme. Hormones are chemical messengers secreted only in blood. Insulin is a hormone secreted by the pancreas to lower blood glucose levels by binding to insulin receptors on cells and stimulating the intake of glucose through glucose transport channels (GLUTs) in the cell membrane.
Answer:
A) The pollen grains will be pure red.
Explanation:
Plants have alternation of generations, this means that there are two different stages in their life-cycle: a sexual haploid (n) phase and an asexual diploid phase (2n). These phases occur in different individuals, so there is an haploid plant called gametophyte that carries gametes and after fecundation, it will rise a diploid sporophyte (asexual).
In seed plants, the sporophyte is the plant that we normally see, and the gametophyte is reduced into an organ of the sporophyte. The male gametophyte is the pollen that is produced in the sporangium in anthers (parts of sporophyte). When a pollen grain fecundes a female gametophyte (egg), it will produce a diploid embryo or new sporophyte.
Therefore, if the researcher exposes pollen to both stains, these grain will stain red, because red stain identifies gametophyte tissue.
Nucleus, The “brains” of the cell, the nucleus directs cell activities and contains genetic material called chromosomes made of DNA.
