Answer:
You can't see the blood vessels themselves because vision depends on a process that makes it impossible to see things that are stationary with respect to the retina. Light receptors in the retina respond only to changes in light reaching them, not to a steady image.
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Answer:
Whereas weather refers to short-term changes in the atmosphere, climate describes what the weather is like over a long period of time in a specific area. ... Looking at Climate Normals can help us describe whether the summers are hot and humid and whether the winters are cold and snowy at a particular place.
Answer:
Explanation:
4 types of mutation:
Germline mutations occur in gametes. Somatic mutations occur in other body cells.
Chromosomal alterations are mutations that change chromosome structure.
Point mutations change a single nucleotide.
Frameshift mutations are additions or deletions of nucleotides that cause a shift in the reading frame.
3 more:
Over a lifetime our DNA can undergo changes or 'mutations?' in the sequence of bases?, A, C, G and T.
This results in changes in the proteins that are made.
Mutations can occur during DNA replication if errors are made and not corrected in time.
Pollen tube growth is one of the most fascinating—and essential—phenomena in the life cycle of flowering plants. After a compatible interaction between pollen grains and the stigma surface, the pollen germinates and forms the pollen tube, which grows through the stigma, style, and transmitting tract to deliver the sperm cells to the ovule."
2) Although pollens of many species germinate in simple aqueous media, stigmas do not provide satisfactory sites for the germination of most foreign pollen... Stigmas not only provide the proper conditions for the germination of pollen from their particular species, they actively inhibit the germination of pollen of many unrelated species.