Presentation Transcript
Slide1 : This lesson will increase your knowledge of concepts covered in the following TEKS for biology: 3.c – Evaluate impact of research on scientific thought, society, and the environment
3.f – Research and describe the history of biology and contribution of scientists
4.a – Identify the parts of a cell
6.a – Describe components of DNA and illustrate how information for specifying the traits of an organism is carried in the DNA
6.b – Explain replication, transcription, and translation using models of DNA and RNA
6.f – Identify and analyze karyotypes
10.a – Interpret the functions of systems in organisms
10.b – Compare the interrelationship of organ systems to each other and to the body as a whole
Slide2 : Previous Lesson Human Development and Stem Cells
Slide3 : Question: What two major processes must occur for a zygote to develop into an adult human being?
Human Development Involves : Human Development Involves Addition of more cells through mitosis
Creation of adult cells with special functions through cell differentiation, creating about 210 different tissues in the body
Slide5 : Question: What is an embryonic stem cell and why does it have potential to revolutionize medicine?
Fig. 22.12 : Fig. 22.12 Embryonic stem cells are undifferentiated cells in the blastocyst
Slide7 : Potential of Stem Cell Research Based on: Time, July 23, 2001
Slide8 : Question: Why is there a controversy over stem cells?
Fig. 22.12 : Fig. 22.12 Harvesting of embryonic stem cells means destruction of an embryo that could live if implanted in the uterus Excess blastocysts from fertility clinics
Today’s LessonDNA and the Human Genome Project : Today’s Lesson DNA and the Human Genome Project
Slide11 : DNA Cloning Cancer Individualism Gene Therapy Human Genome Project DNA Fingerprinting Human Development Genetic Diseases
DNA is the Blueprint for Life : DNA is the Blueprint for Life Each person has a unique complement of DNA
Each person to have a unique complement of proteins
Each person having a unique appearance and behavior
which causes which contributes to THE BIG PICTURE
Overview of Lesson : Overview of Lesson Humans as hunks of protein
DNA and protein synthesis
Human genome project
Slide14 : Humans may be made of up to 2 million different types of proteins Functions of Protein
Structural
muscle, hair
Chemical
antibodies, hormones, enzymes All of the chemical reactions in cells are regulated by enzymes
Slide15 : Proteins are chains of amino acids, usually a few hundred amino acids long AA AA AA AA AA AA AA AA What are proteins made of?
Slide16 : Based on: Mader, S. Inquiry Into Life, McGraw-Hill Examples of Amino Acids
Slide17 : Note: a chain of amino acids is forming as water is removed and amino acids bond together Formation of a Protein Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Slide18 : Protein structure is more than just a chain of amino acids Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Slide19 : Question: How do we make millions of different proteins out of only 20 different amino acids? Answer: The identity and function of each protein is determined by its amino acid sequence and folding
Slide20 : Amino Acid Sequence of Hemoglobin Sickle-cell hemoglobin Box shows the one amino acid difference in normal versus sickle-cell hemoglobin Normal hemoglobin
Slide21 : Based on: Harvard Family Health Guide, 1999 Red Blood Cells
Slide22 : How Do We Get Amino Acids? Eleven of 20 amino acids can be made by the human body
Nine of 20 amino acids cannot be made by the human body. These nine are the “essential amino acids” that must be included in the diet on a daily basis
Overview of Lesson : Overview of Lesson Humans as hunks of protein
DNA and protein synthesis
Human genome project
Slide24 : The structure of DNA (deoxyribonucleic acid) was discovered in 1950s by Watson, Crick, Wilkins and Franklin DNA has a ladder-like shape Based on: Mader, S. Inquiry Into Life, McGraw-Hill
DNA is not a protein, but rather it is the instructions for making proteins : DNA is not a protein, but rather it is the instructions for making proteins
Slide26 : DNA Structure Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Why is DNA shaped like a ladder? : Why is DNA shaped like a ladder?
Slide28 : DNA contains a linear base code that… G - C C - G T - A A - T A - T Proteins which are linear sequences of amino acids Controls
production of… Amino acid Amino acid Amino acid
The Way DNA’s Code WorksThree nucleotides in DNA code for one amino acid in a protein : The Way DNA’s Code Works Three nucleotides in DNA code for one amino acid in a protein
Slide30 : C
G
C
T
A
A
C
G
A Sequence of bases in DNA
are read as triplet codes codes for DNA REGULATION OF PROTEIN SYNTHESIS Amino acid Amino acid Amino acid
So how does DNA regulate protein synthesis in a cell? : So how does DNA regulate protein synthesis in a cell?
Slide32 : DNA is part of the chromosomes in cells Humans have 23 pairs or 46 chromosomes in each cell
Each chromosome has specific genes
Most genes code for the production of specific proteins Based on: Mader, S. Inquiry Into Life, McGraw-Hill
DNA in the chromosomes of the nucleus : DNA in the chromosomes of the nucleus Protein synthesis at the ribosomes DNA Control of Protein Synthesis in Each Cell of the Body Determines
Slide34 : Chromosomes (containing strands of DNA) are in nucleus, the control center of cell
Proteins are made at ribosomes, the protein manufacturing sites of cell Animal Cell Based on: Raven et al., Biology, McGraw Hill
DNA Control of Protein Synthesis : DNA Control of Protein Synthesis DNA uncoils and one strand is used to produce messenger RNA (mRNA) in nucleus
mRNA leaves the nucleus and goes to the ribosomes with copy of blueprint
at the ribosomes, amino acids are linked together as specified by the nucleotide sequence of the mRNA
Slide36 : DNA & PROTEIN SYNTHESIS Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Slide37 : Messenger RNA Codons Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Construction of a Building : Construction of a Building Blueprint in the foreman’s office contains the instructions for the building
Workers take information from the office to the building site
Workers assemble the building out of concrete and steel
Overview of Lesson : Overview of Lesson Humans as hunks of protein
DNA and protein synthesis
Human genome project
Slide40 : The Human Genome Defined as the sum total of genes in
a human
Estimates are 30,000 genes in each
human controlling production of
approximately 2 million different
proteins
Each gene consists of an average of
several thousand bases
Total number of nucleotides is about
3 billion per human cell
Slide41 : Human Genome Project The project began in the late 1980s
supported by 15 billion dollars
Goal of the project was to sequence the
roughly 3 billion chemical letters in DNA
that comprise the genetic code of humans
Many scientists said it could not be done
Project was completed in 2000
- or was it?
Slide42 : The sequence of letters in DNA for the
human genome is known, but the
gene-protein relationships are unknown
It is like having the numbers in a phone
book without the associated names
We are learning the identity of new genes
each day
What We Don’t Know about DNA
Slide43 : Human Proteome Research Scientists will take decades to
figure out which proteins go with
which genes
All of today’s medicine will seem
medieval once proteomics studies
begin to link proteins and genes
because many human diseases are
genetically based
Slide44 : Next Lesson
Individuality and Cloning
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