Cellular organization

1 Cellular organization





Questions



image Why are cells necessary to biology?

image What is the main difference between prokaryotic and eukaryotic cells?

image Why are organelles necessary in eukaryotic cells?


The cell: the unit of biology


The cell is the smallest functional unit of living organisms and tissues. Cellular contents are delineated by a selectively permeable plasma membrane, which permits control over the internal environment. Cells are classified as prokaryotic or eukaryotic on the basis of the absence or presence of a nucleus, respectively.



Prokaryotic cells


Prokaryotic cells, represented by bacteria, are relatively small (1–5 µm in length) simple cells that contain some subcellular structures but are essentially devoid of discrete intracellular membrane-bounded organellar structures (Fig. 3.1.1). All of the cellular contents, including the single circular genomic deoxyribonucleic acid (DNA) molecule, are contained within the cytoplasm. Often, prokaryotic cells are surrounded by a protective cross-linked lattice that forms a cell wall.

Only gold members can continue reading. Log In or Register to continue

Related posts:

  1. Kinases and phosphatases in cell signalling
  2. Ion pumps and ion exchangers
  3. Electrical conduction in nerves
  4. Proteins and protein function

Stay updated, free articles. Join our Telegram channel
Tags:
Jun 18, 2016 | Posted by in BIOCHEMISTRY | Comments Off on Cellular organization

Full access? Get Clinical Tree
Get Clinical Tree app for offline access