Biology

• Biology- the branch of science that deals with the study of living systems and life processes
• Nucleus- most important structure in the cell because it serves as the control center
• Cell wall / Cell membrane- provides tensile strength and protection against mechanical and osmotic stress
• Mitochondrion- power house of cell, where ATPs are abundally synthesized
• Chloroplast – site of photosynthesis among plants and photosynthetic algae
• Ribosome – this serves as the site of protein synthesis.
• Endoplasmic Reticulum – These organelles serve as channels or passageways through

  which materials are transported to the different parts of the cell.
• Centriole – this serves for cytokinetic purposes and is very common among dividing cells
• Lysosome – the structure is also called “suicidal bag” as it releases digestive juices
• Golgi apparatus – this serves for selection and packaging of cellular materials.
• Carbohydrates – immediate source of energy

  elemental composition: C, H, O

  building blocks: monosaccahrides

  • e.g. sucrose (table sugar), maltose, amylase
• Fats/Lipids – these molecules serve as another source of energy after carbohydrates

  elemental composition: C, H, O

  building blocks: fatty acids and a glycerol backbone

  • e.g. waxes, oils, and cholesterol
• Proteins – these molecules serve as sources of building materials.

  elemental composition: C, H, O, N, S

  building blocks: amino acids

  • e.g. amylase, actin and myosin
• Nucleic Acids – these molecules include the RNA’s and the DNA’s

  elemental composition: C, H, O, N, P

  • building blocks: nucleotides
• Prokaryotic cells – have no membrane-bound nucleus and organelles; typical of bacteria

  and blue-green algae
• Eukaryotic cells – have membrane-bound nucleus and organelles; typical of protests,

  fungi, plants, and animals.