Biochemistry Chapter: Water and Biological Macromolecules

Biochemistry and Life Processes

• Water is essential for living things, making up 70-95% of organisms.
• Water is a polar molecule, allowing it to dissolve a wide range of substances, and has a high specific heat, helping to regulate temperature.
• All living things undergo growth, repair, reproduction, gas exchange, metabolism, and response, which involve biological macromolecules.

Biological Macromolecules

• The four main categories of biological macromolecules are:
  • Nucleic acids (made of nucleotides, containing DNA)
  • Proteins (made of amino acids, including enzymes)
  • Carbohydrates (made of monosaccharides)
  • Lipids (made of glycerol and fatty acids)
• All biological macromolecules contain carbon, hydrogen, and oxygen.

Proteins and Enzymes

• Proteins are biological macromolecules that perform a wide range of functions in the cell.
• Enzymes are a type of protein that lower the activation energy of chemical reactions, making them more efficient.
• Enzymes are specific to the molecules they react with, remain unchanged after a reaction, and work best in specific conditions (e.g. pH, temperature).

Metabolism and Cellular Respiration

• Cellular respiration is the process of generating energy for the cell from glucose and oxygen.
• The equation for cellular respiration is: glucose + oxygen → carbon dioxide + water + ATP (energy)
• ATP is used by the cell to perform various functions, such as muscle contraction.

Photosynthesis

• Photosynthesis is the process of generating glucose and oxygen from carbon dioxide, water, and sunlight.
• The equation for photosynthesis is: carbon dioxide + water + sunlight → glucose + oxygen.
• Photosynthesis occurs in organisms with chloroplasts, such as plants and green algae.

Protein Synthesis

• Protein synthesis is the process of creating proteins from DNA.
• The process involves:
  • Transcription: creating a messenger RNA (mRNA) copy of the DNA sequence.
  • Translation: using the mRNA sequence to build a chain of amino acids.
  • Amino acids are linked together by peptide bonds to form a polypeptide chain.

Cell Structure and Function

• The cell theory states that all living things are composed of cells, cells are the basic units of life, and all cells come from other cells.
• Cell membranes are composed of a phospholipid bilayer.
• Cells have genetic information (DNA) and cytoplasm, which holds the cell's materials.
• The cell cycle involves mitosis, where the cell divides and splits its genetic material into two new daughter cells.

Cell Transport

• Cell transport is the movement of molecules into and out of the cell.
• Types of cell transport include:
  • Diffusion: the movement of molecules from high to low concentration.
  • Facilitated diffusion: the movement of molecules from high to low concentration with the help of a transport protein.
  • Active transport: the movement of molecules from low to high concentration, requiring ATP energy.

Osmosis

• Osmosis is the movement of water from high to low concentration.
• The solute sucks principle: water moves towards the area with higher solute concentration.
• Types of osmotic environments:
  • Isotonic: equal concentration of solutes inside and outside the cell.
  • Hypotonic: lower concentration of solutes outside the cell.
  • Hypertonic: higher concentration of solutes outside the cell.

Cell Specialization

• Cell specialization is the process of cells becoming specialized to perform specific functions.
• Structure dictates function, with cells adapting to their specific roles through changes in shape and form.
• Examples of specialized cells include neurons, red blood cells, and epithelial cells.

Organelles

• Organelles are structures within cells that have specialized functions.

• Examples of organelles include:

  • Nucleus: contains DNA.
  • Mitochondria: generates energy for the cell.
  • Chloroplasts: performs photosynthesis in plant cells.
  • Ribosomes: site of protein synthesis.
  • Vacuoles: stores water and other materials.
  • Cell wall: provides structural support and protection in plant cells.### Cellular Organelles

• Mitochondria: responsible for cellular energy creation through cellular respiration

• Vacuole: used for storage, represented by simple circles with a blank space in them

• Ribosomes: small dots, responsible for protein synthesis

• Nucleus: stores genetic information (DNA) in eukaryotic organisms, located at the center of the cell

• Cell membrane: provides a semi-permeable barrier, represented by a phospholipid bilayer, allowing some substances in and out of the cell

• Cell wall: provides structure and support, another layer of protection, geometric in shape (not in animal cells)

Cellular Classification

• Eukaryotic cells: have a true nucleus and membrane-bound organelles, generally larger and more complex (e.g., plant and animal cells)
• Prokaryotic cells: more primitive, lack membrane-bound organelles, typically smaller and simpler (e.g., bacteria)
• Prokaryotic cell features: no nucleus, DNA is free-floating (nucleoid), ribosomes present for protein synthesis, cell membrane present for cytoplasm containment

Biochemistry and Life Processes

• Water makes up 70-95% of organisms and is essential for living things.
• Water's polar molecule structure allows it to dissolve a wide range of substances.
• Water's high specific heat helps regulate temperature.

Biological Macromolecules

• The four main categories of biological macromolecules are nucleic acids, proteins, carbohydrates, and lipids.
• All biological macromolecules contain carbon, hydrogen, and oxygen.
• Nucleic acids are made of nucleotides and contain DNA.
• Proteins are made of amino acids and include enzymes.
• Carbohydrates are made of monosaccharides.
• Lipids are made of glycerol and fatty acids.

Proteins and Enzymes

• Proteins perform a wide range of functions in the cell.
• Enzymes are a type of protein that lower the activation energy of chemical reactions.
• Enzymes are specific to the molecules they react with and remain unchanged after a reaction.
• Enzymes work best in specific conditions, such as pH and temperature.

Metabolism and Cellular Respiration

• Cellular respiration generates energy for the cell from glucose and oxygen.
• The equation for cellular respiration is: glucose + oxygen → carbon dioxide + water + ATP (energy).
• ATP is used by the cell to perform various functions, such as muscle contraction.

Photosynthesis

• Photosynthesis generates glucose and oxygen from carbon dioxide, water, and sunlight.
• The equation for photosynthesis is: carbon dioxide + water + sunlight → glucose + oxygen.
• Photosynthesis occurs in organisms with chloroplasts, such as plants and green algae.

Protein Synthesis

• Protein synthesis is the process of creating proteins from DNA.
• Transcription involves creating a messenger RNA (mRNA) copy of the DNA sequence.
• Translation involves using the mRNA sequence to build a chain of amino acids.
• Amino acids are linked together by peptide bonds to form a polypeptide chain.

Cell Structure and Function

• The cell theory states that all living things are composed of cells, cells are the basic units of life, and all cells come from other cells.
• Cell membranes are composed of a phospholipid bilayer.
• Cells have genetic information (DNA) and cytoplasm, which holds the cell's materials.
• The cell cycle involves mitosis, where the cell divides and splits its genetic material into two new daughter cells.

Cell Transport

• Cell transport is the movement of molecules into and out of the cell.
• Types of cell transport include diffusion, facilitated diffusion, and active transport.
• Diffusion is the movement of molecules from high to low concentration.
• Facilitated diffusion involves the movement of molecules from high to low concentration with the help of a transport protein.
• Active transport involves the movement of molecules from low to high concentration, requiring ATP energy.

Osmosis

• Osmosis is the movement of water from high to low concentration.
• The solute sucks principle: water moves towards the area with higher solute concentration.
• Types of osmotic environments include isotonic, hypotonic, and hypertonic.
• Isotonic environments have equal concentration of solutes inside and outside the cell.
• Hypotonic environments have lower concentration of solutes outside the cell.
• Hypertonic environments have higher concentration of solutes outside the cell.

Cell Specialization

• Cell specialization is the process of cells becoming specialized to perform specific functions.
• Structure dictates function, with cells adapting to their specific roles through changes in shape and form.
• Examples of specialized cells include neurons, red blood cells, and epithelial cells.

Organelles

• Organelles are structures within cells that have specialized functions.
• Examples of organelles include nucleus, mitochondria, chloroplasts, ribosomes, and vacuoles.
• Nucleus contains DNA.
• Mitochondria generates energy for the cell.
• Chloroplasts performs photosynthesis in plant cells.
• Ribosomes is the site of protein synthesis.
• Vacuoles stores water and other substances.