Myself birthing my 8lb 2oz son :)

Added by: heythereelizabeth
Tags: Natural Child birth
Date: 2010-07-13

The cell is the structural and functional unit of all known living organisms, and is sometimes called the building block of life. Some organisms, such as bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an ostrich egg.

Added by: second
Tags: cell celllife AmasingAnimation
Date: 2007-07-30

Day 1: fertilization: all human chromosomes are present; unique human life begins. Day 6: embryo begins implantation in the uterus. Day 22: heart begins to beat with the child's own blood, often a different type than the mothers'. Week 3: By the end of third week the child's backbone spinal column and nervous system are forming. The liver, kidneys and intestines begin to take shape. Week 4: By the end of week four the child is ten thousand times larger than the fertilized egg. Week 5: Eyes, legs, and hands begin to develop. Week 6: Brain waves are detectable; mouth and lips are present; fingernails are forming. Week 7: Eyelids, and toes form, nose distinct. The baby is kicking and swimming. Week 8: Every organ is in place, bones begin to replace cartilage, and fingerprints begin to form. By the 8th week the baby can begin to hear. Weeks 9 and 10: Teeth begin to form, fingernails develop. The baby can turn his head, and frown. The baby can hiccup. Weeks 10 and 11: The baby can "breathe" amniotic fluid and urinate. Week 11 the baby can grasp objects placed in its hand; all organ systems are functioning. The baby has a skeletal structure, nerves, and circulation. Week 12: The baby has all of the parts necessary to experience pain, including nerves, spinal cord, and thalamus. Vocal cords are complete. The baby can suck its thumb. Week 14: At this age, the heart pumps several quarts of blood through the body every day. Week 15: The baby has an adult's taste buds. Month 4: Bone Marrow is now beginning to form. The heart is pumping 25 quarts of blood a day. By the end of month 4 the baby will be 8-10 inches in length and will weigh up to half a pound. Week 17: The baby can have dream (REM) sleep. Week 19: Babies can routinely be saved at 21 to 22 weeks after fertilization, and sometimes they can be saved even younger. Week 20: The earliest stage at which Partial birth abortions are performed. At 20 weeks the baby recognizes its' mothers voice. Months 5 and 6: The baby practices breathing by inhaling amniotic fluid into its developing lungs. The baby will grasp at the umbilical cord when it feels it. Most mothers feel an increase in movement, kicking, and hiccups from the baby. Oil and sweat glands are now functioning. The baby is now twelve inches long or more, and weighs up to one and a half pounds. Months 7 through 9: Eyeteeth are present. The baby opens and closes his eyes. The baby is using four of the five senses (vision, hearing, taste, and touch.) He knows the difference between waking and sleeping, and can relate to the moods of the mother. The baby's skin begins to thicken, and a layer of fat is produced and stored beneath the skin. Antibodies are built up, and the baby's heart begins to pump 300 gallons of blood per day. Approximately one week before the birth the baby stops growing, and "drops" usually head down into the pelvic cavity.

Added by: watchme
Tags: fertilization
Date: 2007-11-23

The Multiphase Thermoelectric Converter is a direct thermal-to-electrical energy conversion system designed in order to harvest most of the waste heat energy efficiently into electricity, reducing weight and size of space heat radiators, making fusion-powered space propulsion more energy-efficient than ever. The Multiphase Thermoelectric Converter consists of two opposing twisting electromagnetic forces, forming two contra-aligned electrodynamic vortices, for axially and radially compressing a hot ionized gas F=q(v × B) forcing it to expand longitudinally transferring electrodynamically F=i(L × B) ε=(Bℓv sinθ) its energy to a multiphase electrical system to be effectively harvested by diode rectifiers. Wherein, the phase rotation keeps hot plasma centered far from electromagnetic coils, which allow to induce high pressure and withstand very high temperatures for virtually getting closer to the maximum efficiency η=1-(TC/TH), e.g. TC=300K, TH=30000K, η%=99%. Together with the Aneutronic Reactor and Electrodynamic Thrusters, it is to form the most perfect triad for providing a high degree of cleanliness and efficiency for deep space propulsion, with practically no thermal and radioactive waste.

Added by: MFerreiraJr
Tags: Thermoelectric MHD Waste Heat Electrical Energy Electricity Conversion Heat Radiator Thermionic RTG
Date: 2012-01-30

This video show DNA replication which is a fundamental process occurring in all organisms to copy their DNA. Enzymes needed for the process are discussed. In a cell, DNA replication must happen before cell division in order to keep genetic material.

Added by: sana
Tags: Replication DNA nucleotides
Date: 2007-05-15

How are proteins synthesized? This interactive animation will help you to understand the process. For more information about protein synthesis: Legend: Process whereby DNA encodes for the production of amino acids and proteins. This process can be divided into two parts: 1. Transcription Before the synthesis of a protein begins, the corresponding RNA molecule is produced by RNA transcription. One strand of the DNA double helix is used as a template by the RNA polymerase to synthesize a messenger RNA (mRNA). This mRNA migrates from the nucleus to the cytoplasm. During this step, mRNA goes through different types of maturation including one called splicing when the non-coding sequences are eliminated. The coding mRNA sequence can be described as a unit of three nucleotides called a codon. 2. Translation The ribosome binds to the mRNA at the start codon (AUG) that is recognized only by the initiator tRNA. The ribosome proceeds to the elongation phase of protein synthesis. During this stage, complexes, composed of an amino acid linked to tRNA, sequentially bind to the appropriate codon in mRNA by forming complementary base pairs with the tRNA anticodon. The ribosome moves from codon to codon along the mRNA. Amino acids are added one by one, translated into polypeptidic sequences dictated by DNA and represented by mRNA. At the end, a release factor binds to the stop codon, terminating translation and releasing the complete polypeptide from the ribosome Text Reff: http://www.accessexcellence.org/RC/VL/GG/protein_synthesis.html

Added by: tubeman
Tags: proteinsynthesis
Date: 2007-04-01

Transcription of some genes can be induces by specific inducer molecules. Lac operon is an example of such inducible gene which is turned on by lactose present in the cells. This video explains how lactose initiates transcription of lac operon. Edited by Ashraf.

Added by: mnazirokur
Tags: lac operon mechanism E.coli inducable genes
Date: 2007-03-17

This video shows how RNA interference works in the cells. Video reference: Nature.com Info: RNA interference (also called RNA-mediated interference, abbreviated RNAi) is a mechanism for RNA-guided regulation of gene expression in which double-stranded ribonucleic acid inhibits the expression of genes with complementary nucleotide sequences. Conserved in most eukaryotic organisms, the RNAi pathway is thought to have evolved as a form of innate immunity against viruses and also plays a major role in regulating development and genome maintenance. The RNAi pathway is initiated by the enzyme dicer, which cleaves double-stranded RNA (dsRNA) to short double-stranded fragments of 20 25 base pairs. One of the two strands of each fragment, known as the guide strand, is then incorporated into the RNA-induced silencing complex (RISC) and base-pairs with complementary sequences. The most well-studied outcome of this recognition event is a form of post-transcriptional gene silencing. This occurs when the guide strand base pairs with a messenger RNA (mRNA) molecule and induces degradation of the mRNA by argonaute, the catalytic component of the RISC complex. The short RNA fragments are known as small interfering RNA (siRNA) when they derive from exogenous sources and microRNA (miRNA) when they are produced from RNA-coding genes in the cell's own genome. The RNAi pathway has been particularly well-studied in certain model organisms such as the nematode worm Caenorhabditis elegans, the fruit fly Drosophila melanogaster, and the flowering plant Arabidopsis thaliana. The selective and robust effect of RNAi on gene expression makes it a valuable research tool, both in cell culture and in living organisms; synthetic dsRNA introduced into cells can induce suppression of specific genes of interest. RNAi may also be used for large-scale screens that systematically shut down each gene in the cell, which can help identify the components necessary for a particular cellular process or an event such as cell division. Exploitation of the pathway is also a promising tool in biotechnology and medicine. Historically, RNA interference was known by other names, including post transcriptional gene silencing, transgene silencing, and quelling. Only after these apparently-unrelated processes were fully understood did it become clear that they all described the RNAi phenomenon. RNAi has also been confused with antisense suppression of gene expression, which does not act catalytically to degrade mRNA but instead involves single-stranded RNA fragments physically binding to mRNA and blocking translation. info ref: http://en.wikipedia.org/wiki/RNAi

Added by: benchwork
Tags: RNA i RNA interference C elegans
Date: 2007-03-26

DNA and RNA are long chain polymers of nucleotide bases. DNA molecule consists of two strands arranged in a helical structure whereas RNA is composed of a single strand. This video presents comparisons of DNA and RNA structures. Edited by Ashraf.

Added by: technician
Tags: DNA RNA
Date: 2007-09-13

Gluconeogenesis is the process by which glucose is synthesized in the body using non carbohydrate sources of carbon like amino acid and glycerol. This pathway of glucose synthesis is utilized by the body when there is a shortage of carbohydrate. This video explains gluconeogenesis. Edited by Ashraf

Added by: siere
Tags: gluconeogenesis
Date: 2007-03-17

Transcription is the process of making RNA from a DNA template. Several key factors are involved in this process, including DNA, transcription factors, RNA polymerase, and ATP. Several complexes, known as transcription factors, are required for successful transcription.

Added by: benchwork
Tags: Transcription mRNA DNA cell division protein synthesis
Date: 2007-04-09

This video shows the packaging of DNA in the nucleus. One human cell's DNA length is 2 meters, still it fits in to the fraction of the cell, nucleus. Find out how chromosome is organised in cells.

Added by: benchwork
Tags: 3D structure of chromosome DNA in nucelus hisrones
Date: 2007-03-22

Polymerase chain reaction (PCR) enables researchers to produce millions of copies of a specific DNA sequence in approximately two hours. This automated process bypasses the need to use bacteria for amplifying DNA.

Added by: mnazirokur
Tags: pcr
Date: 2009-03-18

We are the Hui Zheng lab at BCM and study Alzheimer's Disease. Thanks everyone for your comments and words of encouragement! We had no idea this would spread like it has, but I guess some of these feelings are universal (and international!). This was all in good fun and took us only a few days to do the filming and editing. If you are caught in a bad project, best of luck and hope you can turn it around soon!/nOur submission for the Molecular and Human Genetics Retreat 2011 at Baylor College of Medicine. We decided to parody Lady Gaga's Bad Romance with a science twist. Many thanks to On the Rocks for the dance moves, and http://tinyurl.com/4lddjag for the mouse video.

Added by: mnazirokur
Tags: bad project
Date: 2011-01-25

The structure of DNA is illustrated by a right handed double helix, with about 10 nucleotide pairs per helical turn. Each spiral strand, composed of a sugar phosphate backbone and attached bases, is connected to a complementary strand by hydrogen bonding (non- covalent) between paired bases, adenine (A) with thymine (T) and guanine (G) with cytosine (C).

Added by: sana
Tags: DNA Structure DNA
Date: 2007-05-15

Human immunodeficiency virus (HIV) is a retrovirus that causes acquired immunodeficiency syndrome (AIDS) a condition in humans in which the immune system begins to fail, leading to life-threatening opportunistic infections.

Added by: sana
Tags: HIV AIDS retrovirus viral core reverse transcriptase
Date: 2007-05-15

Stem cells which serve as the source of all the other specialized cells in the body, both when it forms during embryogenesis and when it replaces cells that have been lost to aging, injury or disease is explained in this science video. This is the first part of 4 videos. These videos are created by RIKEN CDB and they explain the different types of stem cell found in the embryonic body and the adult and illustrate the roles of these "master cells" in development and regeneration. Video REff: http://www.cdb.riken.go.jp This part of video gives general overview of steam cells and other, differentiated cells.

Added by: siere
Tags: stem cell differentiation embrypgenesis embryonic stem cells
Date: 2007-04-02

The cellular immune response As the fruit picking was going on, Brian heard someone shout, “Bless you!” after a fellow fruit-picker let out a loud sneeze. Unbeknownst to poor little Brian, some of the air he was breathing in the orchard was now laden with particles of the influenza virus. While the humoral immune response is underway, some of the influenza viral particles will have been consumed by phagocytes and neutrophils while others would have began infecting other cells such as Brian’s epithelial cells. So, how does the immune system deal with these infected cells? By a battle plan called the cellular immune response. Like the humoral immune response, this is also divided into activation and effector phases. The activation phase begins when an antigen-presenting cell (APC) of the host organism encounters and attacks an invading virus. Meanwhile, other viruses look for nearby epithelial cells to infect. A lysosome containing digestive enzymes combines with the phagosome to process the antigens. The processed antigens combine with MHC class II proteins and are presented on the surface of the APC. The virus also infects Brian’s epithelial cells. Within the infected epithelial cells the virus is processed, attached to an MHC class I protein and is presented on the cell surface. A helper T cell (CD4+) recognizes the displayed antigen on the APC and binds to the MHC class II protein-antigen complex. The activated helper T cell releases chemical messengers such as the cytokine IL-2 and gamma interferon (IFN-g). The effector phase begins when activated cytotoxic T cells (CD8+) which were stimulated to proliferate by the cytokine IL-2, recognize the MHC class I protein-antigen complex on the infected epithelial cells. Cytokines also attract other killer T cells to the site of infection. The activated cytotoxic T cell binds to the MHC class I protein-antigen complex on the surface of the infected epithelial cell. The binding causes the cytotoxic T cell to release a potent chemical called perforin. Perforin perforates the cell membrane of the infected cells causing the cells to lyse (burst) and die. As the viral infection is brought under control, regulatory T cells turn off the activated cytotoxic T cells. Memory T cells remain behind to respond quickly if the same virus attacks again.

Added by: tubeman
Tags: humoral
Date: 2007-09-07

We show the details of casting protein gels, loading and running them. Murat KASAP Gurler AKPINAR

Added by: technician
Tags: SDS AGE
Date: 2007-09-06

This video is made for middle school and high school students. It explains what DNA, RNA are. It also explains the transcription and translation processes. Edited by Ashraf.

Added by: cagatay
Tags: Gene DNA RNA Translation Transcription
Date: 2009-05-27