Currently, Most of the Mass of the Matter of the Universe

question 93

Multiple Choice

Currently, most of the mass of the matter of the universe is believed to consist of:

• A)baryonic matter, made up of protons and neutrons.
• B)tachyonic matter, travelling only faster than the speed of light.
• C)dark matter not made of protons and neutrons.
• D)dark energy.
• E)tiny but very numerous black holes.

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Definitions:

Embryos

Early developmental stages of multicellular organisms following fertilization, during which cells divide and specialize to form the structure and organs of the organism.

Germ Layers

The three primary layers of cells (ectoderm, mesoderm, and endoderm) in the early embryo that develop into all organs and tissues of the body.

Lophophore

A unique feeding structure bearing ciliated tentacles, found in certain marine invertebrates such as bryozoans and brachiopods.

Arthropods

A diverse group of invertebrate animals with exoskeletons, segmented bodies, and paired jointed appendages, including insects, arachnids, and crustaceans.