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Now, a new study reports that at least one species of songbird-and likely many more-already knows how to prep its chicks for a warming world. They do so by emitting special calls to the embryos inside their eggs, which can hear and learn external sounds. This is the first time scientists have found animals using sound to affect the growth, development, behavior, and reproductive success of their offspring, and adds to a growing body of research revealing that birds can "doctor" their eggs.

Curriculum materials for the following topics: HeLa Cells & HPV Genes: Immortality & Cancer, which reviews basic cell biology, tissue culture, and human subjects research in the context of privacy, rights, and compensation. Link: http://www.stemcellcurriculum.org/hela-cells-hpv-genes-immortality-cancer.html · Eggs & Blood: Gifts & Commodities, which addresses the value placed on some bodily tissues/cells and not on others. Link: http://www.stemcellcurriculum.org/eggs-and-blood.html · Disease, Disability, & Immortality: Hope & Hype, which explores the natural physical and cognitive variability in the human population and questions the goal of a "cure" in biomedical research. Link: http://www.stemcellcurriculum.org/disease-disability-immortality-hope-hype.html · Stem Cells & Policy: Values & Religion, which analyzes how policy is shaped in pluralistic societies that require tolerance of different points of view. Link: http://www.stemcellcurriculum.org/stem-cells-policy-values-and-religion.html

The UK's leading cancer charity yesterday welcomed work by British scientists who created a breed of genetically modified hens that can produce cancer-fighting medicines in their eggs. The research could slash the cost of producing drugs and potentially save the NHS millions of pounds.

By calling to their eggs, zebra finch parents may be helping their young prepare for a hotter world brought on by climate change.

Meiosis, the form of cell division unique to egg and sperm production, sets the stage for sex determination by creating sperm that carry either an X or a Y sex chromosome. But what is it about the X or Y that determines sex? Before a meiotic cell divides, its two sets of chromosomes come together and cross over, or swap, segments. The first animation shows normal crossing over, where the X and Y chromosomes exchange pieces only at their tips. The second animation shows a rare mistake in which the Y chromosome transfers a gene called SRY to the X chromosome, resulting in sex-reversed babies. Studies of sex-reversed individuals led researchers to identify the master switch for sex determination, the SRY gene, which tells a fetus to become a boy.

Meiosis, the form of cell division unique to egg and sperm production, sets the stage for sex determination by creating sperm that carry either an X or a Y sex chromosome. But what is it about the X or Y that determines sex? Before a meiotic cell divides, its two sets of chromosomes come together and cross over, or swap, segments. The first animation shows normal crossing over, where the X and Y chromosomes exchange pieces only at their tips. The second animation shows a rare mistake in which the Y chromosome transfers a gene called SRY to the X chromosome, resulting in sex-reversed babies. Studies of sex-reversed individuals led researchers to identify the master switch for sex determination, the SRY gene, which tells a fetus to become a boy.

Because the gene-enzyme system forms a closed loop, it presents us with a classic chicken or egg conundrum: Which came first, genes or the protein enzymes they code for? While the details are still not fully worked out, discoveries over the past few decades have lead researchers to a surprising possible solution: What really came first? Genes that act as enzymes! The RNA World Hypothesis is the idea that before living cells, the genetic code, and the gene/protein cycle ever existed, chains of a chemical called RNA were forming naturally. Once formed, some of these chains were able to function as enzymes, and were even able to evolve by making copies of themselves with slight, accidental modifications.

Sulston worked alone, in silence, hunched over a microscope for eight hours a day. By studying and drawing worms of various ages, he figured out the ancestor and descendants of each of their cells. It was a monumental piece of science. Sulston mapped the complete history of an individual, the comprehensive family tree of a single body. "We had the entire story of the worm's cells from fertilized egg to adult," he later said, upon accepting the Nobel Prize for his work.

Mouse study fingers potential cause of fertility problems, proposing obesity and egg quality link.

Using a pre-drawn template can be helpful during a consultation to explain single gene inheritance. Our template shows one pair of chromosomes for each parent. Each chromosome has a single gene highlighted that can be coloured in to illustrate a gene alteration. You can then show which sperm and/or eggs contain the chromosome with the gene alteration and the different genetic combinations that could be present at conception.

Yep, you have mites living on your face. And in this episode of Gross Science, Anna Rothschild explains how they're eating, laying eggs, dying, and leaking feces. On your face. But don't worry because we've known this since 1841 and it appears to be completely normal?

A kind of salmon that's been genetically modified so that it grows faster may be on the way to a supermarket near you. The Food and Drug Administration approved the fish on Thursday - a decision that environmental and food-safety groups are vowing to fight. This new kind of fast-growing salmon was actually created 25 years ago by Massachusetts-based AquaBounty Technologies. A new gene was inserted into fertilized salmon eggs - it boosted production of a fish growth hormone. The result: a fish that grows twice as fast as its conventional, farm-raised counterpart.

But then on Dec. 22, 1938, Marjorie Courtenay-Latimer came across a strange blue fin poking out of a pile of fish that struck her as extraordinary. With its fleshy, lobed fins and its tough armored scales, the specimen looked very unlike fish we see in our oceans today. That is because the coelacanth has managed to survive in roughly its current form for hundreds of millions of years. In the course of researching this film, we learned all kinds of amazing facts about the coelacanth. For instance, unlike most fish, they give birth to live young. They produce eggs the size of grapefruits, which then hatch internally. From video footage taken by the explorer Hans Fricke - which we used as inspiration for our sets and puppets - we know coelacanths are prone to some odd behavior. They've been spotted doing headstands underwater.

This case study was written for an introductory course for biology majors who are first learning about embryonic development. The case is composed of several parts and involves a storyline about a team of researchers who find frogs and eggs in bamboo plants during a field study. Students consider what these observations mean, learn basics about the stages of animal embryonic development, and make connections to phylogeny and natural selection. Students then apply their understanding of animal embryonic stage development to the chemical atrazine in the environment by examining data from several experiments. As a concluding activity students write a letter to an agency or newspaper of their choosing stating their opinion surrounding the use of atrazine in the environment. The case proceeds in a progressive disclosure format and involves a combination of class discussion, small group work, and homework. Because the case focuses on very basic animal embryonic development, it would also be a great start to a developmental biology course or an embryology course.

This two-minute video provides brief background on the use of zebrafish as a model in studying animal development, before showing a time-lapse sequence of a fertilized zebrafish egg developing into a larva.  The video includes some annotations that help orient the viewer during the time-lapse sequence.  Teachers might want to mute the narration beginning at 0:42 min to avoid giving students too much information.  This phenomenon could stimulate the following driving questions: How does the zebrafish develop from one cell to the many cells that make up the larva? How do the zebrafish cells divide? How are the developing zebrafish cells similar and different from each other? If all cells in the zebrafish develop from the same original cell, then how do some cells develop differently than others? How are cell division and growth related? 

groups of cells in the blastula are synchronized to divide at the same time through mitosis. Some of these cells will eventually give rise to the sand dollar's germ cells. Others will play important roles in various developmental processes, such as cell differentiation, the formation of the digestive system, and the development of the exoskeleton. Despite their different characteristics and roles, all of the sand dollar's cells (except for eggs or sperm) are genetically identical due to mitosis.

Article summarizing cell division with time lapse cell division video of 30hours pro vs eukaryotic division.