Created by Jeff Otjen.
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You did a great job but it's not totally correct, you kind of put the wrong picture to some things. There was nothing about the formation of lacunae in syncitiotrophoblast, the actual primary vili are formed far after the uterine blood start flowing through lacunae and the uterine vessels don't actually grow or move like that, the syncitiotrophoblast is growing and producing proteolitic enzimes which degrade the vessel walls so the blood starts pouring into the lacunae. I know it is hard to draw it like that and everything and you did a really good job on everything else.
omg.....please make more videos, i was trying to study this for around two weeks, but could never really the the picture of it! truly its not as detailed as what im studding, but you need to get the basis in order to understand the details. Thanks, and please continue making videos.
Turtle is right, the villi are formed from the cytotrophoblast that invades into the syncytiotrophoblast.
But a lot of steps are not in this video, primary villi form on day 13 = almost very end of implantaion. By then, the amnion, chorion,... Are already formed.
When the embryo is in the blastocyst stage, that usually marks the end of blastulation. The moment the blastocyst is implanted and burrows itself in the maternal endometrium, gastrulation is initiated, forming the three germ layers which will then differentiate into the different organs of an organism.
+Linges Hels Interestingly, most of my professors and colleagues jokingly refer to developing embryos and fetuses as parasites. There are many types of implantation and placentation; humans develop hemochorial placentas, meaning the embryo completely destroys the maternal spiral arteries in order to form large blood pools (called lacunae) in which the fetal chorionic villi (leeching fingers of trophoblast tissue) float to obtain nutrients and oxygen from maternal blood. Various other species have less invasive placentation patterns such as syndesmochorial placentation, in which this kind of blood vessel destruction only occurs at some spots along the placenta rather than the entire fetal-maternal interface.
Antidepressants are medications that can help relieve symptoms of depression, social anxiety disorder, anxiety disorders, seasonal affective disorder, and dysthymia, or mild chronic depression, as well as other conditions.
They aim to correct chemical imbalances of neurotransmitters in the brain that are believed to be responsible for changes in mood and behavior.
Depression Medications (Antidepressants)
These are the most commonly prescribed type of antidepressant.
Serotonin and noradrenaline reuptake inhibitors (SNRIs) are used to treat major depression, mood disorders, and possibly but less commonly attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety disorders, menopausal symptoms, fibromyalgia, and chronic neuropathic pain.
SNRIs raise levels of serotonin and norepinephrine, two neurotransmitters in the brain that play a key role in stabilizing mood.
Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed antidepressants. They are effective in treating depression, and they have fewer side effects than the other antidepressants.
SSRIs block the reuptake, or absorption, of serotonin in the brain. This makes it easier for the brain cells to receive and send messages, resulting in better and more stable moods.
They are called "selective" because they mainly seem to affect serotonin, and not the other neurotransmitters.