internal structures of prokaryotic cell

• Prokaryotes


  Unicellular organisms whose cells lack a membrane-enclosed nucleus
• Domains of prokaryotes


  • Bacteria
  • Archaea
• Prokaryotes


  • All their intracellular components (proteins, DNA and metabolites) are located together in the cytoplasm enclosed by the cell membrane rather than in separate cellular compartments
  • Lack a membrane-bound nucleus and organelles
• Prokaryotes are fundamentally different from eukaryotes
• Differences between prokaryotes and eukaryotes

  • Unicellularity
  • Cell size
  • Nucleoid
  • Cell division and genetic recombination
  • Internal compartmentalization
  • Flagella
  • Pilli
  • Metabolic diversity

  
• Bacteria and archaea have the following in common: lack a membrane-bound nucleus and organelles, genetic materials (DNA) located in the cytoplasm, biochemical reactions and protein formation occurs in the cytoplasm, are single-celled organisms, can form communities/biofilms, are found everywhere on earth, use diverse sources of energy, have similar sizes and shapes

  
• Differences between bacteria and archaea

  • Pathogenicity
  • Photosynthesis
  • Glucose oxidation
  • Habitats
• Cocci


  Round cells, sometimes slightly flattened when they are adjacent to one another
• Bacilli


  Rod-shaped bacteria

  
• Spirilla


  Curved bacteria which can range from a gently curved shape to a corkscrew-like spiral, many are rigid and capable of movement, a special group known as spirochetes are long, slender, and flexible

  
• Arrangements of cocci


  • Diplococci
  • Streptococci
  • Tetrads
  • Sarcinae
  • Staphylococci
• Arrangements of bacilli


  • Single bacillus vs Diplobacilli
  • Streptobacilli
  • Coccobacilli
  • Palisades
• Arrangements of spiral bacteria

  • Vibrio
  • Spirilla
  • Spirochetes

  
• Other bacterial arrangements and shapes

  • Filamentous bacteria
  • Star-shaped bacteria
  • Rectangular bacteria
  • Pleomorphic bacteria

  
• Lactobacillus is an example of a "good" bacteria
• Prokaryotes differ greatly in size, ranging from nanobacteria (0.05-0.2 µm) to Epulopiscium fishelsoni (600 x 80 µm)
• Prokaryotes are much simpler than eukaryotic cells and are considered to be early forms of life on Earth
• Hormones are chemical messengers produced by glands, which travel through the bloodstream to target organs or tissues where they bind to specific receptors.
• The endocrine system is responsible for producing hormones that regulate various bodily functions.
• Endocrine disorders can occur when there is an imbalance in hormone production or sensitivity, leading to symptoms such as weight gain, fatigue, mood changes, and irregular menstrual cycles.
• The endocrine system consists of various glands that produce hormones, including the pituitary gland, thyroid gland, adrenal glands, pancreas, ovaries/testes, and pineal gland.
• The hypothalamus acts as a control center for the endocrine system, regulating the release of hormones from other glands.
• Examples of hormone-producing glands include the pituitary gland, thyroid gland, adrenal glands, pancreas, ovaries/testes, and hypothalamus.
• Some examples of hormones produced by these glands include growth hormone, insulin, testosterone, estrogen, cortisol, and prolactin.
• The endocrine system plays a crucial role in maintaining homeostasis within the body.
• Examples of hormones include insulin, glucagon, growth hormone, cortisol, testosterone, estrogen, progesterone, melatonin, and thyroid hormones.
• Some common examples of endocrine disorders include diabetes mellitus, hypothyroidism, hyperthyroidism, Cushing's syndrome, Addison's disease, and polycystic ovary syndrome.
• Diabetes Mellitus is characterized by high levels of glucose in the blood due to insulin resistance or deficiency, resulting in symptoms like increased thirst, frequent urination, blurred vision, and slow healing wounds.
• Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormone, causing symptoms like fatigue, weight gain, cold intolerance, constipation, dry skin, hair loss, and depression.
• Each gland has its own unique function and produces different types of hormones.
• Some common examples of hormonal disorders include diabetes mellitus, hypothyroidism, hyperthyroidism, Cushing's syndrome, Addison's disease, polycystic ovary syndrome, and acromegaly.
• The pituitary gland produces several important hormones, including growth hormone (GH), prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyrotropin (TSH), corticotropin (ACTH), melanocyte-stimulating hormone (MSH), and antidiuretic hormone (ADH).
• Diabetes Mellitus - A condition characterized by high levels of glucose in the blood due to insulin resistance or deficiency, resulting in symptoms like increased thirst, frequent urination, blurred vision, and slow healing wounds.
• What is the primary function of DNA?

  Replication, transmission, and providing a molecular blueprint for cells.
• What is the significance of the DNA blueprint?

  It provides instructions for the synthesis of proteins, which perform crucial cellular functions.