The cytoskeletion determines cell shape. The cytoskeleton consists of three different types of filamentous proteins: microfilaments, intermediate filaments, and microtubules. Elements of the cytoskeleton can interact with the cell membrane and cell junctions to alter the cell's overall structure.

There are no cell walls in animal cells, although the cell wall does play a large part in determining cell shape in organisms that possess them (plants, bacteria, fungi).

The unstable form of energy that is syntheisized refers to ATP. ATP is an unstable; its three phosphate groups are all negatively charged and repel one another. Remember that BOTH the mitochondria and chloroplast participate in ATP synthesis via chemiosmosis; however, only the chloroplast participates in glucose synthesis via photosynthesis. Note that glucose is a stable form of energy and is not readily usable until it is broken down in the process known as glycolysis.

The nucleolus is a subdivision of the nucleus; thus, it is only found in eukaryotes. It is the site of ribosome assembly. The nucleolus is made of RNA and proteins.

Histones are proteins found in the nucleus of eukaryotic cells. DNA wraps itself around histones to further condense. Also, depending on how tightly the DNA is wrapped around the histones, it may or may not be availible for activity (e.g. replication or transcription). Cells modify the interaction between DNA and histones around certain genes under certain conditions to make those genes available or unavailable as needed.

Vacuoles are membrane-bound structures that are found in bacterial, plant, fungal, and occasionally, animal cells. Vacuoles function in storage of water and waste and in maintenance of turgor pressure in plants. 

Prokaryotic cells are defined as cells that lack membrane-bound organelles, such as the nucleus. Prokaryotic cells still have DNA as their genetic material, however it is located in the cytoplasm in a circular structure known as the nucleoid. The nucleoid is unique to prokaryotes because it lacks a nuclear envelope.

Prokaryotic cells have cytoplasm contained inside of a plasma membrane, and often a cell wall. They also have ribosomes in the cytoplasm to carry out protein synthesis.

Eukaryotes are much more complex and have numerous organelles, including the endoplasmic reticulum, Gogli apparatus, lysosomes, and mitochondria.

Much like eukaryotes, prokaryotes are capable of translating their own proteins. Prokaryotes follow the same central dogma as eukaryotic cells, using DNA to transcribe mRNA and using mRNA and ribosomes to build proteins from amino acids. Ribosomes are primarily composed of rRNA, and are not bound by a membrane.

Prokaryotes lack a nucleus, as well as complex membrane-bound organelles such as mitochondria and chloroplasts.

The primary difference between prokaryotes and eukaryotes is the presence of membrane-bound organelles. Prokaryotes lack any membrane-bound organelles, including a nucleus, while eukaryotes possess these structures. All cell types have an outer cell membrane, which contains the cytosol, DNA, and ribosomes. Ribosomes are not bound by membranes, and are essential for translating proteins. Both prokaryotes and eukaryotes use transcription to convert DNA to RNA and translation to convert RNA to proteins.

Mitochondria are only found in eukaryotes and are used to produce ATP via oxidative phosphorylation. A circular chromosome is characteristic of prokaryotes, since they lack a nucleus. Both prokaryotes and eukaryotes can have cell walls.

Prokaryotes are much smaller in size than eukaryotes. Eukaryotes are known for their membrane-bound organelles, such as the mitochondria, vesicles, and vacuoles. Prokaryotes do not have membrane-bound organelles. Some eukaryotic organisms go through the process of meiosis in order to produce variation for sexual reproduction.

Prokaryotes undergo a different process to reproduce asexually, called binary fission. The DNA of prokaryotes are contained in a circular chromosome called a nucleoid, which is replicated completely. The cell then splits in two, with each having an exact copy of the same plasmid. Prokaryotes lack a nucleus by definition. 

The prokaryotic ribosome is smaller, at 70S, while the eukaryotic ribosome is larger, at 80S. The ribosomes also contain different sized subunits. Prokaryotic ribosomes are made of a 30S and 50S subunit to form the full 70S structure. Eukaryotic ribosomes are made of a 40S and 60S subunit to form the full 80S ribosome.

Eukaryotes and prokaryotes split during evolution when eukaryotic cells adapted membrane-bound organelles. These organelles include the endoplasmic reticulum, mitochondria, chloroplasts, Golgi apparatus, and nucleus (among others). Prokaryotes lack all of these structures.

All cells, however, contain DNA and ribosomes in order to synthesize proteins and maintain metabolic processes. Ribosomes are not bound by membranes, and are instead made of ribosomal RNA (rRNA) and proteins. Both prokaryotes and eukaryotes can have cell walls, though the structure and composition of the cell wall can vary.