Solution:
According to the accepted current theory, known as the fluid mosaic model, the plasma membrane is composed of a double layer (bilayer) of lipids, oily substances found in all cells. The fluid mosaic model was first proposed by S.J. The fluid mosaic model describes the structure of the plasma membrane as a mosaic of components —including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character. Plasma membranes range from 5 to 10 nm in thickness.
Thus this is the required answer.
<span>D.Oxygen will diffuse from an area of higher concentration (outside the cell) to an area of lower concentration (inside the cell). This is because cells respire constantly, as this process uses up oxygen cells will contain less oxygen than its surroundings. Oxygen moves by the process of diffusion, in diffusion a molecule will always move from a higher concentration to a lower concentration.</span>
an increase in atmospheric carbon dioxide
Answer: D
Answer:
Dimetrodon (/daɪˈmiːtrədɒn/ (About this soundlisten)[1] or /daɪˈmɛtrədɒn/,[2] meaning "two measures of teeth") is an extinct genus of non-mammalian synapsid that lived during the Cisuralian (Early Permian), around 295–272 million years ago (Ma).[3][4][5] It is a member of the family Sphenacodontidae. The most prominent feature of Dimetrodon is the large neural spine sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Most fossils have been found in southwestern United States, the majority coming from a geological deposit called the Red Beds of Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was first erected in 1878.
Explanation:
Dimetrodon is often mistaken for a dinosaur or as a contemporary of dinosaurs in popular culture, but it became extinct some 40 million years before the first appearance of dinosaurs. Reptile-like in appearance and physiology, Dimetrodon is nevertheless more closely related to mammals than to modern reptiles, though it is not a direct ancestor of mammals.[4] Dimetrodon is assigned to the "non-mammalian synapsids", a group traditionally called "mammal-like reptiles".[4] This groups Dimetrodon together with mammals in a clade (evolutionary group) called Synapsida, while placing dinosaurs, reptiles and birds in a separate clade, Sauropsida. Single openings in the skull behind each eye, known as temporal fenestrae, and other skull features distinguish Dimetrodon and mammals from most of the earliest sauropsids.
The first difference is the size, cells are sized in micrometer (visible at optic microscope) and viruses in nanometer (electronic microscope).
Cells have both DNA and RNA, virus have only one genetic material (DNA or RNA).
Cells have always a membrane, not all the viruses have a membrane, but all of them have capsids in different forms.
Viruses cannot live on their own, they have to parasite a cell to proliferate. Cells can live by themselves and proliferate by scissiparity (divisions).
Cells have ribosomes to translate their RNA. viruses don't (they use the infected cells' ribosomes).
