What are special structures in cell membrane that allow material such as water and sugar to pass through made of?
Which cell structures are most directly involved in the production and transport of proteins out of the cell?
A canonical example of an autopoietic system is thebiological cell,. The eukaryotic cell, for example, is made of various biochemical components such as nucleic acids and proteins, and is organized into bounded structures such as the cell nucleus, various organelles, a cell membrane and cytoskeleton.
Chromatin is made of histone proteins. It is used for DNA packing. The DNA winds around it like little spools. In eukaryotes, this occurs in the cell nucleus. Prokaryotes do not have a cell nucleus although their DNA does wrap around small structures which only resemble the histone proteins of eukaryotes.
Describe the characteristics that distinguish proteins from the other major classes of macromolecules and explain the biologically important functions of this group?
Proteins are made of amino acids. Carbohydrates, DNA and fat are not made of amino acids. Protein is the building block of life. Most of the structures (e.g. feathers, hair, the external skeleton of insects, the sting of a bee and a jelly fish, etc.) found in nature are made of proteins. Even single celled organisms must rely on proteins. The cell membrane is made of proteins and lipids, and the flagellum of single cell…
Cell communication deals with either mutual recognition between cells, usually by specific interaction between their surface molecules called membrane glycoproteins. Or the process in which a cell recognizes or identifies its environment. In order to respond to changes in their immediate environment, cells must be able to receive and process signals that originate outside their borders. Individual cells often receive many signals simultaneously, and they then integrate the information they receive into a unified action…