What Makes Up A Cell?
A. Compounds that contain both hydrogen and carbon are called organic, others are inorganic
B. Inorganic Substances
Water
a. Water is the most abundant compound in living things and makes up two-thirds of the weight of adults.
b. Water is an important solvent so most metabolic reactions occur in water.
c. Water is important in transporting materials in the body since it is a major component of blood.
d. Water carries waste materials and can absorb and transport heat.
Oxygen
a. Oxygen is needed to release energy from nutrients and is used to drive the cell’s metabolism. Grabs electron. Why does oxygen want to grab electrons? _______________________________________
How many electrons are in oxygens outer shell? ________________
Carbon Dioxide
a. Carbon dioxide is released as a waste product during energy-releasing metabolic reactions. When do you produce more CO2? ___________________________
Inorganic Salts
a. Inorganic salts are the sources of ions of sodium, chloride, potassium, calcium, magnesium, phosphate, carbonate, bicarbonate, and sulfate.
b. These electrolytes play important roles in many of the body’s metabolic processes.
C. Organic Substances
Carbohydrates
Carbohydrates provide energy for cellular activities and are composed of carbon, hydrogen, and oxygen.
Carbohydrates are made from monosaccharides (simple sugars); disaccharides are two monosaccharides joined together; complex carbohydrates (polysaccharides), such as starch, are built of many sugars.
Humans synthesize the polysaccharide glycogen, which is the major storage form of glucose in the body. Glycogen is formed when multiple glucose molecules are linked together in a branched chain.
What are the two most common places that we store our glycogen stores? ________________________
Glucose is easily added and broken off glycogen. Is having glucose readily accessible an advantage? ____________________________
What is the advantage of storing glucose in a branched chain? _____________________________________
Lipids
a. Lipids are insoluble in water but soluble in certain organic solvents: lipids include fats, phospholipids, and steroids.
Will lipids dissolve in water? (Yes or No) _____________________
Will oils float on top of water? (Yes or No) ____________________
b. Fats supply energy, are composed of oxygen, carbon, and hydrogen, and are built from glycerol and three fatty acids.
Fatty acids with hydrogen at every position along the carbon chain are saturated; those with one or more double bonds are called unsaturated fats.
c. Phospholipids contain glycerol, two fatty acids, and a phosphate group, and are important in cell membrane structures.
d. Steroids are complex ring structures, and include cholesterol, which is used to synthesize the sex hormones.
Proteins
Proteins perform a variety of functions in the body including:
1.structural materials
2. energy sources
3. certain hormones
4. receptors on cell membranes
5. antibodies
6. enzymes to catalyze metabolic reactions.
Enzymes do things in the body
Proteins contain C, O, H, and nitrogen atoms; some also contain sulfur.
Building blocks of proteins are amino acids,
Proteins have complex shapes. Each unique shape allows for different functions and actions in the body. Proteins are often held together by hydrogen bonds.
Protein shapes, which determine how proteins function, can be altered (denatured) by pH, temperature, radiation, or chemicals.
Nucleic Acids
- Nucleic acids form genes and take part in protein synthesis.
- They contain nucleotides.
- Nucleic acids are of two major types: DNA and RNA.
RNA (ribonucleic acid) functions in protein synthesis to “make stuff.”
DNA (deoxyribonucleic acid) stores the genetic code.