Follow us On YouTube Follow us On FaceBook



or
Search Language
Browse
Medical Animations
Medical Animation Titles
Custom Legal Animations
Patient Health Articles
Most Recent Uploads
Body Systems/Regions
Anatomy & Physiology
Diseases & Conditions
Cells & Tissues
Diagnostics & Surgery
Cardiovascular System
Digestive System
Integumentary System
Nervous System
Reproductive System
Respiratory System
Back and Spine
Foot and Ankle
Head and Neck
Hip
Knee
Shoulder
Thorax
Medical Specialties
Cancer
Cardiology
Dentistry
Editorial
Neurology/Neurosurgery
Ob/Gyn
Orthopedics
Pediatrics
Account
Administrator Login
Biology: The Cell: 13: Cell Division - Meiosis - Medical Animation
 
This animation may only be used in support of a single legal proceeding and for no other purpose. Read our License Agreement for details. To license this animation for other purposes, click here.

If animation does not play, download and install the latest free Flash Player plugin.
More Like ThisAdd To Lightbox NSV16019 Enlarge
Ready to Purchase?

$999.00

Order by phone: (800) 338-5954
Item #NSV16019Source #1

Biology: The Cell: 13: Cell Division - Meiosis - Medical Animation
MEDICAL ANIMATION TRANSCRIPT: In this lesson, we'll explore the details of what happens during the phases of meiosis. Meiosis, sometimes called reduction division, is the type of cell division that produces gametes. By gametes, we mean sex cells such as sperm cells in males and egg cells in females. Meiosis is broken down into two stages of cell division called meiosis I and meiosis II. Meiosis I has four phases: prophase I, metaphase I, anaphase I, and telophase I. And meiosis II also has four phases: prophase II, metaphase II, anaphase II, and telophase II. Let's look at what happens during meiosis I. Prophase I starts with a diploid cell. Its chromatin contains two uncoiled, spread out sets of chromosomes, one from each parent. After the DNA in the chromatin replicates, it condenses into the more familiar X-shaped chromosomes. The replicated DNA is the same in the identical sister chromatids of each chromosome. In a process called synapsis, each chromosome pairs up with and binds to its corresponding homologous chromosome, forming a tetrad. A tetrad is the group of four sister chromatids in paired homologous chromosomes. The chromosomes contain genetic information called genes. These genes were inherited from each parent, and different versions of the same gene on each chromosome are called alleles. In a process called crossing over, chromatids from each homologous chromosome exchange segments of alleles. Also called recombination, crossing over randomly happens on every chromosome, resulting in different gene combinations. This explains why every gamete is genetically different from every other gamete. Crossing over results in genetic variety in offspring. This is why children are different from their biological parents, as well as from their biological siblings. Continuing on with prophase I, the nuclear membrane disappears, the centrioles move to opposite ends of the cell, and spindle fibers fan out from them. Next, in metaphase I, the homologous chromosomes line up at the equator and attach to spindle fibers from opposite poles. During anaphase I, spindle fibers separate the homologous chromosomes in each tetrad and pull them to opposite poles of the cell. The cell enters telophase I with one chromosome from each homologous pair at separate poles. However, each chromosome still consists of sister chromatids. Keep in mind that each chromosome's sister chromatids are no longer identical because of the allele exchange that happened during crossing over. Then spindle fibers disappear and the nuclear membrane re-forms around the chromosomes. Finally, cytokinesis occurs. Meiosis I ends with two genetically different haploid daughter cells. Each haploid cell contains only one set of chromosomes consisting of paired sister chromatids. Both cells now enter the next stage, meiosis II. However, unlike meiosis I, DNA does not replicate before meiosis II begins. Once again, in prophase II, the nuclear membrane disappears, and spindle fibers fan out from the two sets of paired centrioles. During metaphase II, the chromosomes in each cell line up at the equator and attach to spindle fibers from both poles. During anaphase II, the sister chromatids of each chromosome separate and move to opposite poles. Once the sister chromatids separate, they are called chromosomes. Finally, during telophase II, the spindle fibers disappear, and nuclear membranes re-form, and cytokinesis occurs in both cells. Meiosis II ends with four genetically different haploid daughter cells, each containing only one set of chromosomes. Some key points to remember about meiosis. It begins with a diploid cell. Meiosis only produces gametes. Gametes are genetically different haploid cells, sperm cells in males and eggs in females. Meiosis has two stages of cell division called meiosis I and meiosis II. During meiosis I, homologous chromosomes separate to produce two haploid cells, each containing chromosomes in the form of paired sister chromatids. In meiosis II, the sister chromatids separate in both cells, becoming individual chromosomes. Cytokinesis of these cells produces four genetically different haploid gametes. And here are some key points to remember about prophase I. The pairing of homologous chromosomes called synapsis occurs. Each pair of homologous chromosomes, consisting of four chromatids, is called a tetrad. During the process of crossing over, chromosomes in homologous pairs exchange segments of alleles. Crossing over results in genetic differences in gametes. All gametes produced by meiosis are haploid. [music]

YOU MAY ALSO WANT TO REVIEW THESE ITEMS:
Right Scapulothoracic Bursitis with Multiple Attempts at Surgical Repair
Right Scapulothoracic Bursitis with Multiple Attempts at Surgical Repair - exh5773
Medical Exhibit
Add to my lightbox
Find More Like This
Perineal Region of Female - Bartholin's Glands
Perineal Region of Female - Bartholin's Glands - BI00026
Medical Illustration
Add to my lightbox
Find More Like This
Front and Back Male Figures with Post-accident Electrical Burn Injuries
Front and Back Male Figures with Post-accident Electrical Burn Injuries - exh46502a
Medical Exhibit
Add to my lightbox
Find More Like This
Biology: The Cell: 11: Cell Division - Haploid vs. Diploid
Biology: The Cell: 11: Cell Division - Haploid vs. Diploid - NSV15017
Medical Animation
Add to my lightbox
Find More Like This
Biology: The Cell: 14: Cell Division - Mitosis vs. Meiosis
Biology: The Cell: 14: Cell Division - Mitosis vs. Meiosis - NSV15013
Medical Animation
Add to my lightbox
Find More Like This
Biology: The Cell: 12: Cell Division - Overview of Meiosis
Biology: The Cell: 12: Cell Division - Overview of Meiosis - NSV15016
Medical Animation
Add to my lightbox
Find More Like This
What attorneys say about MLA and The Doe Report:
"This past year, your company prepared three medical illustrations for our cases; two in which we received six figure awards; one in which we received a substantial seven figure award. I believe in large part, the amounts obtained were due to the vivid illustrations of my clients' injuries and the impact on the finder of fact."

Donald W. Marcari
Marcari Russotto & Spencer, P.C.
Chesapeake, VA

"[I] have come to rely upon the Doe Report and your great staff of illustrators for all my medical malpractice cases. … Please know that I enthusiastically recommend you to all my colleagues.

Frank Rothermel
Bernhardt & Rothermel
"Medical illustrations are essential evidence in personal injury litigation and MLA is simply the best I've found at producing high-quality illustrations. Your illustrators are not only first-class artists, but creative and responsive. Your turn around time is as good as it gets. My clients have won over $60 million in jury verdicts and I can't recall a case which did not include one of your exhibits. On behalf of those clients, thanks and keep up the great work!"

Kenneth J. Allen
Allen Law Firm
Valparaiso, IN
www.kenallenlaw.com

"I wanted to take some time out to let you know what a wonderful job you did with the 'collapsed lung/fractured rib' illustrations. They were both detailed and accurate. My medical expert was comfortable working with them and he spent at least an hour explaining to the jury the anatomy of the lungs, the ribs and the injuries depicted in the illustrations. Needless to say, the jury was riveted to the doctor during his testimony.

The jury returned a verdict for $800,000.00 and I'm sure we would not have done so well if not for the visualizations we were able to put forth with your assistance. Lastly, my special thanks to Alice [Senior Medical Illustrator] who stayed late on Friday night and patiently dealt with my last minute revisions."

Daniel J. Costello
Proner & Proner
New York, NY













Awards | Resources | Articles | Become an Affiliate | Free Medical Images | Pregnancy Videos
Credits | Jobs | Help | Medical Legal Blog | Find a Lawyer | Hospital Marketing