1Syllabus Information: Genetics BIOL 3313

Dr. David F. Gilmore Office: 418 LSE• Email: dgilmore@astate.edu

• Web page: http://www.clt.astate.edu/dgilmore • Office hours: TBA; other times by appt.

2Syllabus info (continued)

• Four lecture exams (100 pts each)• Fifth exam at Finals time (100 pts)• Additional points for homework, quizzes, other

assignments.

Attendance sheet

These PowerPoints: Note number, take scant notes; slides will be posted before class.

3Genetics:

the Study of Biological Information• How is the information stored/organized?

• How is it used?

• How is it transmitted to new generations?

• How is it distributed among populations?

4Genetics:

the Study of Biological Information

• How is the information stored?

• How is it used?

• Look at the information storage molecule itself.

• Look at how the information is processed and the products of that information.

5Genetics: the Study of Biological Information

• How is it transmitted to new generations?

• How is it distributed among populations?

• Look at how information is passed on at the cellular level and what info shows up in the offspring.

• Look at patterns of inheritance in families, quantify how traits persist and are distributed within populations.

64 Major Divisions/Approaches in Genetics

Classical genetics: look at patterns of inheritance, note how genes act by observing inherited characteristics.

Molecular genetics: Reductionist approach, determine how genes work by examining and manipulating their molecular structure.Population genetics: Use of statistics and math to see how traits are passed on, maintained, or lost among large numbers of individuals.

Cytogenetics: learning about inheritance by studying cell structures, particularly chromosomes.

7A Book on How to Make Gargoyles: An analogy about genetic information

8A Book on How to Make Gargoyles: An analogy about genetic information

Questions about the book itself: color, weight, # of pages?

Book as source of information: organization? Number of chapters?

Information independent of book

9A Book on How to Make Gargoyles: An analogy about genetic information

Phenotype vs. genotype: what’s on your friend’s roof?

Vertical vs. horizontal transmission: who gets a copy of the book?

10Using genetic information:the “central dogma”

Proteins can be directly responsible for traits.

Enzymes (proteins) can create traits:metabolize sugars; synthesize pigments or vitamins; assemble other informational macromolecules like polysaccharides.

11Lipids

• Fatty acids, phospholipids, cholesterol, steroid hormones, etc.– Hydrophobic; components of membranes, can diffuse

through membranes• Steroid hormones bind to receptors with specificity

– Result in changes in gene expression– Have information content, change information usage

www.pandasthumb.org/archives/images/lock&key.jpg

12Carbohydrates

• Simple sugars, oligosaccharides, polysaccharides– Polysaccharides include

structural/storage materials such as starch, cellulose, peptidoglycan, glycogen, chitin.

– Some oligosaccharides (on glycoproteins, glycolipids) have specific, complex structures:

– Information contentwine1.sb.fsu.edu/BCH4053/Lecture15/Lecture15.htm

13Proteins

• Sequence of amino acids determines eventual 3-D structure.

• Sequence itself directly coded for by DNA

• Proteins have high degree of information content.

http://www.cs.nott.ac.uk/~nxk/TEACHING/G6DHLL/COURSEWORK/2003-2004/courseworks_files/image009.gif

14Nucleic acids

• The ultimate informational molecules

• Genetic information determined by sequence of nucleotide bases.

http://www.fhcrc.org/science/education/courses/cancer_course/basic/img/dna.gif

15Review of Cell Structure

• Eukaryotes: larger, and compartmentalized– Feature membrane-bound organelles– DNA enclosed in nucleus, associated with histones

• Capable of being tightly packaged• Prokaryotes: small and structurally simple

– Membrane-bound organelles lacking– DNA loosely packaged with histone-like proteins

• Never tightly packaged• Attached to inside of cell membrane

16Eukaryotic cell surface features• All cells have a phospholipid/protein bilayer membrane,

the interface between the cell and its environment.• The cell coat consists of

informational molecules: polysaccharides and PS-containing lipids and proteins.

These molecules act as receptors to identify the cell or receive messages that trigger changes in gene expression. Green: proteins; blue: PS; red: lipids.

http://www.sju.edu/biology/CellsPowerPt/chp11/img030.jpg

17The Nucleus and CytoplasmOrganelle with a double membranePores allow passage of materials.

DNA packaged with proteins = Chromatindiffuse, granular apperance.

Nucleolus: rRNA and ribosome synthesis

137.222.110.150/ calnet/cellbio/page4.htm; http://www.sp.uconn.edu/~bi107vc/images/cell/cytoplasm.gif

Cytoplasm is a colloid of protein and water

Contains the other organelles and membrane systems such as endoplasmic reticulum and the ribosomes, site of protein synthesis.

18More organelles• Ribosomes, endoplasmic reticulum, and Golgi work

together to create and distribute proteins– After synthesis on ribosomes, proteins acquire sugar tags in ER

and are sorted and shunted after being prepared in Golgi.• Ancient endosymbionts

– Mitochondria resemble Gram negative bacteria (2 membranes) in many ways, are self replicating and have own DNA

• Site of aerobic respiration, ATP synthesis• DNA is circular like bacterial; bacterial-type ribosomes.

– Chloroplasts similar and carry out photosynthesis; have own DNA

19Centrioles and cytoskeleton• The centrioles are structures that occur in

pairs and are made of microtubules.– Microtubules are made of protein– Centrioles help assemble the spindle to which

chromosomes attach in mitosis.• The cytoskeleton is made of microtubules

and microfilaments– Proteins are generally tubulin or actin– Provides cell shape, structure and locomotion.

cell.sio2.be/noyau/4.php ; www.cellsalive.com/ cells/cytoskel.htm

20Prokaryotes• No organelles, little or no cytoskeleton• Cell wall surrounding cell membrane,

so membrane surface not heavily involved in receiving signals.

• Small size and lack of nucleus allow rapid responses to changes in the environment.

• Ribosomes plentiful, but smaller and different from eukaryotic.

http://ghs.gresham.k12.or.us/science/ps/sci/soph/cells/pics/pro1.jpg