Biopedia: January 2013

Unit-2

Chemical and cellular basis of life

https://www.google.lk/url?url=http://www.youtube.com/watch%3Fv%3DAJ2d2q2G2oE&rct=j&sa=X&ei=OworUebyEI6SrgeUvYHwDg&ved=0CF0QuAIwBg&q=rose+flower+blooming+you+tube&usg=AFQjCNEgZDs0QNsHz35GAla_AOMbkKxhaw

http://www.youtube.com/watch?feature=player_detailpage&v=Wnx9thXySGw

http://www.youtube.com/watch?feature=player_detailpage&v=cFX4JrsPaUshttp://www.youtube.com/watch?feature=player_detailpage&v=37Eyq6K0GPg

http://www.youtube.com/watch?feature=player_embedded&v=lE-RKRNSG_c

http://www.youtube.com/watch?feature=player_detailpage&v=caoneXrvp9k

http://www.youtube.com/watch?feature=player_detailpage&v=1PcnCWZP7l0

http://www.youtube.com/watch?feature=player_detailpage&v=cFX4JrsPaUs

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter3/protein_denaturation.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter3/simple_gene_expression.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter3/dna_structure.html

http://www.youtube.com/watch?feature=player_detailpage&v=gW3qZF9cLIA

http://www.youtube.com/watch?feature=player_detailpage&v=GcrndR-zdyM

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter3/simple_gene_expression.html

http://www.youtube.com/watch?feature=player_detailpage&v=f4Gicf7ONGA

http://www.mhhe.com/biosci/multilevel/majors_bio/Chemistry/Question4/index.html

http://www.youtube.com/watch?feature=player_detailpage&v=yqESR7E4b_8

http://www.youtube.com/watch?feature=player_detailpage&v=PEDQoQuIhkg

http://www.youtube.com/watch?feature=player_detailpage&v=Ikq9AcBcohA

Hirarchical organization of living systems

Cell Theory

http://orion.chemi.muni.cz/e_learning/=Animace/11-Lipidy/10-2a_FluidMosaic/FluidMosaic.htm

http://www.youtube.com/watch?feature=player_detailpage&v=Qqsf_UJcfBc

http://www.youtube.com/watch?feature=player_detailpage&v=9kuO16IgQYg

http://www.goldiesroom.org/Note%20Packets/06%20Transport/00%20Transport--WHOLE.htm

http://www.youtube.com/watch?feature=player_detailpage&v=moPJkCbKjBs

http://www.youtube.com/watch?feature=player_detailpage&v=C7XliJVJhok

http://www.youtube.com/watch?feature=player_detailpage&v=C7XliJVJhok

http://www.youtube.com/watch?feature=player_detailpage&v=QGAm6hMysTA

Cells and tissues contribute to the functioning of organisms

In multi cellular organisms , the cells are organized into tissues , organs and organo systems

Tissue is a group of physically linked cells with common origin specialized for a paticular function or functions

Animal Tissues

Epithelial Tissue

Connective Tissue

Cartilege

Bones

Blood

Muscle Tissue

Nervous Tissue

The process of cell division

Cell division results a genetically identical daughter cells

Interphase

This is a period of intense synthesis and growth in the cell. The cell produces many materials required for its own growth and activities. The genetic material DNA replicates during interphase.

Karyokinesis

It is the process of nuclear division, which involves separation of chromatids and their redistribution as chromosomes into daughter cells.

Cytokinesis

It is the process of division of the cytoplasm to result in the formation of daughter cells.

Cell Cycle

The length of the cycle depends on the nature of cell and various external factors like temperature food and oxygen availability. Bacterial cells may divide every 20 minutes, epithelial cells living the small intestine divide once in 8 to 10 hours, onion root tip cells take about 20 hours to divide. Some specialised cells like the nerve cells never divide.

Cytokinesis

It is the division of the cytoplasm

In animals

A cleavage furrow appears at the begining of Telophase
The furrow deepens as spindle breaks down
The ingrowing constrictions join and seperate two daughter cells

In plants

There is a formation of cell plate between two daughter cells
This grows from the middle towards the peryphery and finnaly joins the cell wall
The cell plate represents the middle lamella between the walls of two adajacent cells

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9nTLp5TGtw0DGk4bcREXo_Usb0i6TiTt-eOxVPe_hMn3pypds56EK5h4bZQUwv6MM2MzIR3LntoTW_M6oQ4ag2SOJOP6dkAXm70O0-HGMFOcb6LHlpyjr7X5sB0QKON2SYIWBw8rC5DQ/s1600/cytokinensis+in+animals.jpg

Meosis

http://www.youtube.com/watch?feature=player_detailpage&v=Q6ucKWIIFmg

http://www.sbs.utexas.edu/levin/bio213/genetics/mitosis.gif

http://cdn.c.photoshelter.com/img-get/I0000jWtxX4TCrgs/s/860/860/Fphoto-64720907B-6WRc.jpg

http://www.youtube.com/watch?feature=player_detailpage&v=4B071d9Ywbc

http://www.youtube.com/watch?feature=player_detailpage&v=cvlpmmvB_m4

Mitosis Meiosis I

Prophase ProphaseI

Homologous chromosoms do not pair Homologous chromosoms pair

Synapsis and crossing over

occur

Metaphase Metaphase I

Individual homologues align Paired homologous

on metaphase plate Chromosomes align

on metaphase plate

Anaphase Anaphase I

Sister chromatids separate Homologous chromosomes

seperate

Telophase    Telophase I
Cytokinesis occurs    Cytokinesis occurs   Sister

chromatids remain together

and two cells result,

Meiosis II

Each containing

Chromosomes align,

the original number Sister chromatids seperate

of chromosomes and four haploid cells result,

Each containing half the

original number of homologues

http://www.youtube.com/watch?ture=player_detailpage&v=Ba9LXKH2ztU

http://www.youtube.com/watch?feature=player_embedded&v=ZkJMVxafyoU

Significance of mitosis

It keeps the chromosome numberconstant and genetic stability in daughter cells.

It helps in growth and develpoment of zygote into adult through embryo formation

It provides new cells for repair and generation of lost parts and healing of wounds
It helps in sexual reproduction

Significance of meiosis

It maintains a constant number of chromosomes by producing haploid gametes.

Due to crossing over in meiosis , organisms may exchange genes and cause genetic variations in species.This variations serve the raw material of evolutionary process.

Chromosomal and genomic variations are the sources of useful variations.

http://www.biologyexams4u.com/2012/09/difference-between-mitosis-and-meiosis.html#.UTMGhaKLDfI

The energy relationship to metabolic process

http://www.youtube.com/watch?feature=player_detailpage&v=Lx9GklK0xQg

The role of enzymes in regulating metabolic reactions

Enzyme combines with substrates to form short lived enzyme- substrate complexes.

Within this complex reactions between enzyme and substrate take place.

Once the reaction is completed complex breaks up to products and

enzymes .

Enzymes remain unchanged and is free to react with new substrate

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter6/how_enzymes_work.html

Enzymes are specific, combined with substrates to form enzyme- substrate complexes through active sites

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter6/a_biochemical_pathway.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter6/feedback_inhibition_of_biochemical_pathways.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter6/enzyme_action_and_the_hydrolysis_of_sucrose.html

http://www.rsc.org/Education/Teachers/Resources/cfb/enzymes.htm

Photosynthesis as an energy fixing mechanism

Visible light is a very small pottion of the electro magnetic spectrum.Photosynthetic organisms use some of the wavelengths of visible light to provode energy for food production

http://faculty.southwest.tn.edu/rburkett/GB-1%20photosynthesis.htm

http://www.southtexascollege.edu/modeh/1408webpage_files/CH%207.htm

Overview of C3 photosynthesis

Calvin Cycle

http://mandevillehigh.stpsb.org/teachersites/laura_decker/calvin_cycle.htm

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter8/cyclic_and_noncyclic_photophosphorylation.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter8/photosynthetic_electron_transport_and_atp_synthesis.html

http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter8/calvin_cycle.html

http://highered.mcgraw-hill.com/sites/0070960526/student_view0/chapter5/animation_quiz_1.html

http://www.biologycorner.com/APbiology/cellular/notes_photosynthesis1.html

http://www.phschool.com/science/biology_place/biocoach/photosynth/electro.html

http://www.bbc.co.uk/schools/gcsebitesize/science/images/photosyn_1.gif

Leaf anatomy of C3 plant Leaf anatomy of C4 plant

C3 plants only have C4 plants show different

mesophyl cells anatomical features /

circle of bundle sheath

cells around vascular

bundles in leaves

Light reaction Calvin cycle reaction

http://faculty.southwest.tn.edu/rburkett/GB-1%20photosynthesis.htm

Water and oxygen cycle between chloroplasts and mitochondria within a plant cell, as do glucose and carbon dioxide . Cells with chloroplast require an outside source of carbon dioxide and water and generate glucose and oxygen. Cells without chloroplasts, such as animal cells, require an outside source of glucose and oxygen and generate carbon dioxide and water

Cellular respiration as a process of obtaining energy

www.zazzle.ca/detailed_diagram_of_cellular_respiration_poster-228685310922658856

It is not necessary to memorize these steps, but an understanding of each process is necessary in order to understand normal physiology and abnormal conditions that may interfere with respiration and possibly lead to death.

Note the role of NAD as a hydrogen acceptor (carrier), and note how many molecules of NAD and FAD are used. What eventually happens to the hydrogen that is passed to NAD and FAD?

The last half of glycolysis, where a net gain of two ATPs occurs.

When oxygen levels are not sufficient, pyruvate is converted into lactate in our muscles by the use of the enzyme LDH. Yeasts have different enzymes, and convert pyruvate into ethyl alcohol, a process utilized in brewing. Note that no more energy (ATP) is obtained by these processes.

Glucose, proteins, and lipids may be processed into Acetyl Co-A.

http://www.phschool.com/science/biology_place/biocoach/cellresp/practice1.html

http://www.phschool.com/science/biology_place/biocoach/cellresp/review2.html

Various amino acids may be converted into the molecules found within the KCAC, and may be utilized as fuel.

The beginning of the Krebs cycle, in which the first two CO₂s are produced.

Remember that for each molecule of glucose, two Acetyl Co-A molecules are produced; therefore the KCAC occurs twice for each glucose, so all products here are X 2..

The ETS uses Cytochoromes, iron containing pigments, each of which has a slightly higher electronegativity than the previous one used; this allows hydrogen electrons and ions to gradually be passed to the final step, which is the combination of hydrogen and oxygen, to produce water. Note that 6 molecules of water enter into the reactions at various steps, and that 12 molecules are produced in the end. The original simplified formula is sometimes shown with 6 additional water molecules on each side of the equation.

http://www.phschool.com/science/biology_place/biocoach/cellresp/krebs.html

http://www.phschool.com/science/biology_place/biocoach/cellresp/review3.html