Cell

• The understanding / study of biologically important molecules or also known as biomolecules from its source — living organisms.
• • ORDER

  Organisms are highly organized coordinated structures that consist of one or more cells.
• • SENSITIVITY 
  • or response to stimuli
• • Positive response: movement towards the stimulus
• Negative response: movement away from the stimulus
• • REPRODUCTION

  ability to reproduce
• Single-celled organisms reproduce by first replicating their DNA, and then dividing it equally as the cell prepares to divide to form new cells. (Mitosis)
•  When reproduction occurs, DNA containing genes are passed along to an organism’s offspring. (Meiosis)
• • GROWTH AND DEVELOPMENT
  • Organisms grow and develop as a result of genes providing specific instructions that will direct cellular growth and development
• • REGULATION

  Humans have control systems or points of regulation
• Even the smallest organisms are complex and require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses.
• • HOMEOSTASIS
  • Balance or steady state
• HOMEOSTASIS - Refers to the relatively stable internal environment required to maintain life
• • ENERGY PROCESSING
  • Organisms use a source of energy for their metabolic activities
• 1. Chemical Level

  • Atoms bond to form molecules with three-dimensional structures
  • Atoms bond to form a compound
• 1. Cellular Level

  • A variety of molecules combine to form the fluid and organelles of a body cell
• 1. Tissue Level

  • A community of similar cells form a body tissue
• 1. Organ Level

  • Two or more different tissues combine to form a body tissue
• 1. Organ System Level

  • Two or more organs work closely together to perform the functions of a body system
• 1. Organismal Level

  • Many organ system work harmoniously to perform the function of an independent organism
• Humans are considered organic because we have CARBON.
• • Cells -  the building blocks of all living organisms
• 4 COMPONENTS IN CELLS

  1. An enclosing plasma membrane which separates the cell’s interior from the environment.
  2. Cytoplasm made of cytosol in which other components of the cell are found
  3. DNA - genetic material of the cell
  4. Ribosomes which synthesize proteins
• • CELL THEORY

  An underlying principle of biology

  1. Cells are basic unit of life
  2. All living organisms are made up of cells
  3. All cells come from preexisting cells
• An enclosing plasma membrane which separates the cell’s interior from the environment.
• 1. Cytoplasm made of cytosol in which other components of the cell are found
• DNA - genetic material of the cell
• Ribosomes which synthesize proteins
• Cytosol - refers to the fluid part of the cytoplasm
• Unicellularity or single-celled
• Smaller than eukaryotes. Most prokaryotes are less than 1 mm in diameter
• Nucleoid. Prokaryotic chromosome is single, circular, double-stranded DNA found in the nucleoid region of the cell
• Most divide by binary fission (separates to divide)
• Genetic recombination occurs through horizontal gene transfer. No sexual reproduction
• Flagella is simple in structure
• • Metabolic diversity. 
  • Oxygenic photosynthesis: 

  Found in plants; produces oxygen as a byproduct and uses water as an electron donor.
• CHARACTERISTICS OF PROKARYOTES 

  1. Lack membrane-enclosed internal compartments (eg. nucleus)
  2. Have a cell wall containing peptidoglycan
  3. Believed to be much like the first cells (components are simple)
  4. Belong in the domains Archaea and Bacteria
• Chromosomal DNA is localized in nucleoid
• Ribosomes are in the cytoplasm
• Cell membrane is surrounded by a cell wall