Connective Tissue & Prokaryotic Cells Notes PDF

Connective Tissue: Supports the body and provides a "frame" for epithelial cells to perform their functions Connective tissues are the primary contributors to stroma (i.e., support structure) Examples include: bone, cartilage, tendons, ligaments, adipose tissue, and blood *A major d...

Connective Tissue: Supports the body and provides a "frame" for epithelial cells to perform their functions Connective tissues are the primary contributors to stroma (i.e., support structure) Examples include: bone, cartilage, tendons, ligaments, adipose tissue, and blood *A major defining feature of connective tissue is the presence of an extracellular matrix (ECM) Classi cation and Structure of Prokaryotic Cells Prokaryotes do not contain any membrane-bound organelles Prokaryotes also do not contain a nucleus; instead, they possess a nucleoid region, which is a single circular DNA molecule concentrated within this region All of life is organized into three domains: 1) Archaea; 2) Bacteria; and 3) Eukarya Prokaryotes are only found in archaea or bacteria domains Initially, Archaea and Bacteria were classified into the same kingdom known as Monera. Archaea are single-celled organisms that appear visually similar to bacteria; however, they contain several metabolic pathways and genes that are more similar to eukaryotes compared to bacteria Historically, Archaea were considered extremophiles (i.e., organisms that can survive and thrive in harsh environments) Archaea are known for their ability to use alternative sources of energy; they have also been shown to survive in nonharsh conditions (e.g., the human body) Some Archaea are photosynthetic; many, however, are chemosynthetic and can generate energy from inorganic compounds, including sulfur- and nitrogen-based compounds It is hypothesized that Archaea and Eukaryotes originated from a common ancestor: for example, both Archaea and Eukaryotes begin translation with the amino acid methionine Additionally, both Archaea and Eukaryotes possess similar RNA polymerases, and both associate their DNA with histones However, Archaea contain only a single chromosome, divide by binary fission or budding, and share similar structural features with bacteria Notably, Archaea are resistant to a wide variety of antibiotics