Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis  Gene—DNA segment that carries a blueprint for building one protein

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis  Gene—DNA segment that carries a blueprint for building one protein  RNA is needed for protein synthesis

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis  Gene—DNA segment that carries a blueprint for building one protein  RNA is needed for protein synthesis  Transfer RNA (tRNA).  Ribosomal RNA (rRNA).  Messenger RNA (mRNA).

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis  Gene—DNA segment that carries a blueprint for building one protein  RNA is needed for protein synthesis  Transfer RNA (tRNA)--Transfers amino acids to ribosome for building the protein  Ribosomal RNA (rRNA)--Helps form the ribosomes where proteins are built  Messenger RNA (mRNA)--Carries instructions for building protein from nucleus to ribosome

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings You will need to know…  The functions of: mRNAtRNArRNA

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Translation

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Translation GCC TTT ATA AGG CAT DNA

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Translation AUG CCU UAU AAA … GCC TTT ATA AGG CAT DNA mRNA

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Transfer of information from DNA’s base sequence to the complimentary base sequence of mRNA  Three-base sequences on mRNA are called codons  Translation

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Translation (leaves nucleus) AUG CCU UAU AAA … GCC TTT ATA AGG CAT AUG CCU UAU AAA … DNA mRNA

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Translation (leaves nucleus) AUG CCU UAU AAA … GCC TTT ATA AGG CAT AUG CCU UAU AAA … Met- Pro- Tyr - Lys … DNA Amino acid chain— will become a protein mRNA

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Transcription and Translation  Transcription  Transfer of information from DNA’s base sequence to the complimentary base sequence of mRNA  Three-base sequences on mRNA are called codons  Translation  Base sequence of nucleic acid is translated to an amino acid sequence  Amino acids are the building blocks of proteins

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Path of information: DNA  RNA  Protein Transcription: in nucleus Translation: at a ribosome

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 1 Nucleus (site of transcription) DNA mRNA specifying one polypeptide is made on DNA template Cytoplasm (site of translation ) Nuclear pore Nuclear membrane mRNA 1) mRNA is formed

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 2 Nucleus (site of transcription) DNA mRNA specifying one polypeptide is made on DNA template mRNA leaves nucleus and attaches to ribosome, and translation begins Cytoplasm (site of translation ) Nuclear pore Nuclear membrane mRNA Small ribosomal subunit Large ribosomal subunit Codon UG C CAU 2) mRNA leaves nucleus, joins ribosome

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 3 Nucleus (site of transcription) DNA mRNA specifying one polypeptide is made on DNA template mRNA leaves nucleus and attaches to ribosome, and translation begins Synthetase enzyme Amino acids Cytoplasm (site of translation ) Correct amino acid attached to each species of tRNA by an enzyme Nuclear pore Nuclear membrane mRNA Small ribosomal subunit Large ribosomal subunit Codon UG C CAU 3) tRNA linked to amino acid

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 4 Nucleus (site of transcription) DNA mRNA specifying one polypeptide is made on DNA template mRNA leaves nucleus and attaches to ribosome, and translation begins Synthetase enzyme Amino acids Cytoplasm (site of translation ) Correct amino acid attached to each species of tRNA by an enzyme Nuclear pore Nuclear membrane mRNA Small ribosomal subunit tRNA “head” bearing anticodon Large ribosomal subunit Incoming tRNA recognizes a complementary mRNA codon calling for its amino acid by binding via its anticodon to the codon Codon UG C CAU 4) tRNA carries amino acid to ribosome

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 5 Nucleus (site of transcription) DNA mRNA specifying one polypeptide is made on DNA template mRNA leaves nucleus and attaches to ribosome, and translation begins Synthetase enzyme Amino acids Cytoplasm (site of translation ) Correct amino acid attached to each species of tRNA by an enzyme Growing polypeptide chain Nuclear pore Nuclear membrane mRNA As the ribosome moves along the mRNA, a new amino acid is added to the growing protein chain Direction of ribosome advance; ribosome moves the mRNA strand along sequentially as each codon is read Small ribosomal subunit tRNA “head” bearing anticodon Large ribosomal subunit Peptide bond Incoming tRNA recognizes a complementary mRNA codon calling for its amino acid by binding via its anticodon to the codon Codon Ala Phe Ser Gly Met CGG GCUCAG C CAU 5) Ribosome connects amino acid to chain

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Protein Synthesis Figure 3.16, step 6

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Aptitude Check  Can you:  Describe the structure and function of the cell parts?  Distinguish between types of transport?  Identify the stages of mitosis?  Describe the functions of 3 types of RNA?  Describe the processes of translation and transcription?

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Body Tissues  Tissues--Groups of cells with similar structure and function

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Body Tissues  Tissues--Groups of cells with similar structure and function  Four primary types  Epithelial tissue (epithelium)  Connective tissue  Muscle tissue  Nervous tissue

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelial Tissues  Locations  Body coverings, linings, glands  Functions  Protection  Absorption  Filtration  Secretion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelium Characteristics  Cells fit closely together and often form sheets  The apical surface is the free surface  The lower surface rests on a basement membrane  Avascular (no blood supply)  Regenerate easily

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelium Characteristics Figure 3.17a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Classification of Epithelia  Number of cell layers  Simple—one layer  Stratified—more than one layer Figure 3.17a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Classification of Epithelia  Shape of cells  Squamous (flat)  Cuboidal  Columnar Figure 3.17b

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple squamous  Forms membranes lining body cavities, lungs and capillaries Single layerflat cells The thinnest epithelium– promotes diffusion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple cuboidal  Common in glands and their ducts  Forms walls of kidney tubules  Covers the ovaries Single layercubic cells Thicker--promotes secretion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18b

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple columnar  Often includes mucus-producing goblet cells  Lines digestive tract Single layertall cells Best epithelium for mucus production

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18c

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Pseudostratified columnar  Often looks like a double layer of cells  Sometimes ciliated, such as in the respiratory tract  May function in absorption or secretion Not really more than one layer tall cells Cilia move mucus

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18d

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Stratified squamous  Cells at the apical surface are flattened  Found as a protective covering where friction is common (skin, mouth and esophagus) Layersflat cells Oldest, driest, deadest cells are on the surface

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia Figure 3.18e

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Stratified cuboidal  Stratified columnar  (can be mixed) (Two) LayersCubic cells LayersTall cells

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Transitional epithelium  Shape of cells depends upon the amount of stretching  Lines organs of the urinary system “Changing”

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia Figure 3.18f

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Glandular Epithelium  Gland--cells responsible for secreting a product  Two types:  Endocrine gland  Exocrine gland

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Glandular Epithelium  Gland--cells responsible for secreting a product  Two types:  Endocrine gland  Ductless: secretions diffuse into blood vessels  Secretions are hormones  Exocrine gland  Secretions empty through ducts to the epithelial surface  Include sweat and oil glands