Cell Biology

Leeuwenhoek's microscope

Later, in the 17th century, Anton van Leeuwenhoekenlightened the world to what he dubbed “animacules”such as protozoa found in standing water. He was the first to identify sperm and red blood cells

Zacharias Janssen invented the first compound microscope in 1595

Microscopes

Cell Fractionation

Fig. 4-1, p. 75

1 μm

AtomAminoacids

Protein

Ribosomes

Virus

Mitochondrion

0.1 nm

Smallestbacteria

1 nm 10 nm 100 nm 10 μm

Chloroplast

Nucleus

10 m1 m100 mmElectron microscope

Light microscope

10 mm

Typicalbacteria

Red bloodcells

Epithelialcell

Humanegg

Frog egg

Chickenegg

Somenerve cells

Adulthuman

1 mm100 μm

Measurements1 meter = 1000 millimeters (mm)1 millimeter = 1000 micrometers (μm)1 micrometer = 1000 nanometers (nm)

Human eye

Carbon Atoms

• form four covalent bonds– single, double, or triple– straight or branched chains– rings

• bond with many different elements

Fig. 3-1, p. 46

Table 3-1a, p. 49

Table 3-1b, p. 49

Figure 2.5

H2O

Polaridad

Cohesividad

Retiene calor

Solvente

Figure 2.8

Fig. 3-13, p. 58

Fatty acidsCholine

PhosphategroupGlycerol

Hydrophilichead

Hydrophobictail

Water

Ionización del Agua

*Escala de pH

Figure 2.9

[ H+ ] =1 X 10-7 M [ OH- ] = 1 X 10-7 M

H2O H+ + OH-

pH = 2 [H+] = 0.01

pH = 5 [H+] = 0.00001

pH = 8 [H+] = 0.000000001

pH = 10 [H+] = 0.0000000001

Moléculas orgánicasen los organismos vivos

Monómeros, Polímeros o macromoléculas

Polymers and Macromolecules

• Polymers – long chains of monomers – linked through condensation reactions

• Macromolecules – large polymers– polysaccharides, proteins, and DNA– broken down by hydrolysis reactions

Condensation and Hydrolysis

Estructura y función de las proteínas

1953 James Watson, Francis Crick y Rosalind Franklin

DNA MoleculeNucleic Acid

Nucleic Acid

• RNA

Nucleotides

• ATP (adenosine triphosphate)– essential in energy metabolism

• NAD+ – electron acceptor in biological oxidation and

reduction reactions

Monosaccharides

Fig. 3-6, p. 51

Disaccharides

Polysaccharides

• Long chains– repeating units of simple sugar

• Storage polysaccharides– starch in plants – glycogen in animals

• Structural polysaccharide– cellulose, cell walls of plants– chitin in arthropods

• Starch • Glycogen

Cellulose

**chitosan

Chitin

• Triglycerides = three fatty acids attached to one molecule of glycerol

Figure 2.15

Lipids

Triacylglycerol

Fatty acids

Figure 2.13

Fig. 3-13, p. 58

Fatty acidsCholine

PhosphategroupGlycerol

Hydrophilichead

Hydrophobictail

Water

Steroids• Carbon atoms arranged in 4 rings

– cholesterol, bile salts, some hormones

Figure 2.16 Steroids

Figure 2.16