Invertebrate doesn't posses "Backbone" whereas Vertebrate chordate have that. That's the only & most important difference between them.
Hope this helps!
B. Spermatogenesis.
Make gametes are called sperm, and
Spermato-sperm
genesis-creation
The Prostate gland
The prostate is a walnut-sized organ that surrounds the
first part of the urethra. It is located between the bladder and the penis. Semen
is formed by the prostate by combining a thick white fluid it initially produced
with the sperm from the testicles. It also produces an antibiotic protein known
as prostate-specific antigen (PSA) that changes the semen into liquid.
Scientific Theory change but not thrown away because scientist
continue looking for possibilities and exact proportion to prove such theory,
though it is change because they always conducted hypnosis in every theory and
once it proves something different they conduct another hypothesis for more
actual evidence.
Answer: B. The smallest part of an atom
Explanation:
Electrons are the smallest of the three particles that make up atoms. Electrons are found in shells or orbitals that surround the nucleus of an atom. Protons and neutrons are found in the nucleus. They group together in the center of the atom.