A. Water falls from the atmosphere as rain, ice, or snow
Mutations are caused by changes in nucleotide bases. these altered base formed different amino acid depending upon nucleotide base sequence that code specific amino acid. ... even though some mutations, can have a more effect on amino acid coding, which can affect what kind of proteins are produced.
Answer:The Cycad tree is the sporophyte.They have flagellated sperm.
Explanation:
During pollination, the contents of the megaspore divide to form many–celled gamateophyte called the endosperm and archegonium. There is a micropyle opening with a sticky fluid, which traps the wind-borne male gametophyte (microspores) which,at this time is made up of prothallus cell;an antheridial cell and a large tube cell. The trapped microspore is sucked into the archegonia chamber. Antherizoids are released, but only one penetrates each oospore and fuses with the female nucleus. The zygote is formed in the ovule and the later develops into seed.The diploid seed germinates into a new sporophyte plant and the life cycle begins again. Examples of cycad include Cycas circinalis ,Cycas celebrical and Cycas revoluta
Answer:
conscious neural control
Explanation:
Neural control of digestive tract is unconscious achieved via the autonomic nervous system.
Local nervous system of the digestive system is called the enteric or intrinsic nervous system. The major components of this nervous system are two networks or plexuses of neurons:
• The myenteric plexus – controls digestive tract motility
• The submucous plexus - regulates gastrointestinal blood flow and controls epithelial cell function.