Question

Compare and contrast 10 structural and genetic characteristics that distinguish between “Prokaryotic” and Eukaryotic cells. Be sure to define/describe the significance of the characteristics that you mention.

Answer 1

Characteristics	Prokaryotic cells	Eukaryotic cells
Size	Typically 0.2 to 2.0 micrometer in diameter.Because of this small size ions and some organic molecules can easily spread to the other cells and wastes are easily moved out from cells.	Typically 10 to 100 micrometer in diameter. This cells have larger size than prokaryotic cells because eukaryotic cells have nucleus and other cell membrane bound organelles hence that allows for compartmentalization function.
Cell membrane	Cells is enveloped by the rigid cell wall. Bacterial cells lack a membrane bound nucleus hence their genetic materials are naked within the cytoplasm so the rigid cell wall protects the cells . Gram positive bacteria cell wall is made up of peptidoglycons. Gram negative bacteria cell wall is made up of lipopolysaccharides	Cell is enveloped by the flexible plasma membrane. The plasma membrane controls the passage of organic molecules, ions ,water and oxygen into and out of the cells.
Sub cellular organelles	Absent . Because they are unicellular organisms so they not contains sub cellular organelles. And prokaryotic cells were defined by their lack of membrane bound organelles.	Distinct organelles are found (eg. Mitochondria, nucleus, cytoplasm). These structure plays very important roles in the normal functioning of the cells. They participate in everything from constructing and exporting newly synthesized biological molecules to protecting the cell from invading pathogens.
Nucleus	Not well defined , DNA is found as nucleoid . Histones are absent. Because of absent of nuclear membrane their(nucleus) shape is not defined. Hence they are present in cytoplasm as a nucleoid.	Well defined nucleus, surrounded by a membrane. That membrane is commonly reffered to as a nuclear envelope. That contains pores that allow material to move in and move out . DNA is associated with histones. The nucleus is the house of genetic materials .
Energy metabolism	Mitochondria is absent . Hence enzymes of energy metabolism are bound to membrane. Most prokaryotes get their energy from simple sugars. Some are phototrophs get energy from sunlight. Others are chemotrophs getting energy from chemical compounds . Some are autotrophs and others are heterotrophs . They can perform aerobic or anaerobic metabolic pathways.	Enzyme of energy metabolism are present in mitochondria. Mitochondria converts energy stored in glucose into ATP for the cell.
Cell division	Usually fission (binary fission). No mitosis. Prokaryotes do not have nucleus so they divided by binary fission, where one cell elongates, duplicate the DNA and plasmids and seperated into two new cells using z ring.	Mitosis. It is the multi step process in which nucleus of the cell is divided.
Cytoplasm	No cytoskeleton or cytoplasmic streaming . Cytoplasm of a cell is a fluid in nature that fills the cell and is composed 80% of water that also Contains enzymes ,salt, cell organelles and various organic molecule.	Contains cytoskeleton and cytoplasmic streaming . The cellar matrix is collectively called a s cytosol. Cytoplasmic filaments are also present in Cytoplasm. And also that contains several enzymes, metabolites , salt . This is aqueous gel like medium .
Flagella	Consist of two protein building blocks. It aids in cellular locomotion and also that is act as the sensory organalle.	Consist of multiple microtubules and they are complex . Also known as cilia. They are used for cell moving, reproduction and cell feeding . And they perform many function in animal
Glycocalyx	Present as a capsule or slime layer .	Present in some cells that lack a cell wall.
Ribosomes	Small size ribosomes(70S) . They are freely float in the cytosol. Hence that is only free form. It is the work bench of protein synthesis. Small and large subunits size are 30S and 50S respectively	Larger size (80S). They are free and bound form. Eukaryotic cells have Mitochondria and chloroplast as organelle they both also have a 70S ribosomes . Small and large subunits size are 40S and 60S respectively.
Chromosome (DNA) arrangements	Single circular chromosome, lacks histones.	Multiple linear chromosomes with histones
Sexual reproduction	No meiosis , transfer of DNA fragments only ( conjunction). Bacteria and archae reproduce through asexual reproduction known as binary fission.	Involves meiosis. This process typically involving an alteration between haploid generations, wherein only one copy of each chromosome is present,and diploid generations wherein two are present, occuring through nuclear fusion(syngamy) and meiosis. There is considerable variation in this pattern.