Answer:
The correct option is a. lacks organelles beyond ribosomes.
Explanation:
All cells of higher organisms are bounded by a cell membrane (also called plasma membrane or plasmalema) and contain cytoplasm that surrounds one or more nuclei. Within the cytoplasm there are structures known as organelles, which are specialized in carrying out the metabolic processes of the cell, these cells are called eukaryotes. The prokaryotes are smaller, lack a differentiated nucleus and organelles. The prokaryotic cells are not internally divided by membranous walls, but consist of a single space.
Both prokaryotic and eukaryotic cells contain ribosomes. Ribosomes are organelles not delimited by membranes, these organelles are important since a cell makes all its proteins in its ribosomes.
Hi!
Magnetic force is a non-contact force.
Answer:
Ptolemy included epicycles in his orbits.
Explanation:
Ptolomy's model of the solar system was geocentric, where the sun, moon, planets, and stars all orbit the earth in perfectly circular orbits. The problem with perfectly circular orbit around the Earth is that they do not explain the occasional backward motion, or retrograde motion, of the planets.
The Greeks insisted that the motion of the planets be perfectly circular. Ptolemy modeled the planets making small circles around a point that orbited the Earth. These smaller circles were called epicycles, and they allowed the planets to move backward relative to the background stars.
(Pp)(Yy) —> PY, Py, pY, py
