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Le rythme cardiaque

S1 E8
·
2014

Although the heart is an automatic organ, it is covered with nerve fibers that connect it to the bulbar nerve center located at the base of the brain. A constant exchange of information between this cerebral region and the cardiac region allows the heart to regulate its beat frequency in an involuntary manner and to maintain it within a normal value, around 70 to 75 beats per minute.

Levels:
Élémentaire 5e année Secondaire 10e année 11e année
Subjects:
Sciences et technologie Biologie Systèmes vivants
Skills:
Apprentissage autonome Pensée critique
French level:
B2 : Avancé ou indépendant C1 : Autonome
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E16 : Le cycle ovarien

4 min 13 s
From puberty to menopause, the woman's body lives to the rhythm of the ovarian cycle. A cycle that lasts 28 days, which regulates constant changes in the female reproductive system. Between the formation of oocytes and the role of estrogens, day after day, a detailed review of this complex precision mechanism...
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E17 : La régulation du cycle ovarien

3 min 1 s
The ovarian cycle is regulated by a whole series of antagonistic hormones whose quantity present in the blood varies throughout the 28 days of the cycle. How do the brain and the reproductive system control each other's functioning?
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E18 : Le fonctionnement du testicule

3 min 11 s
Sperm production in the seminiferous tubules of the testicle is regulated by testosterone, the production of which is itself controlled by hormones secreted by the hypothalamic-pituitary complex, located at the base of the brain. But testosterone itself acts in return on the brain...
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E19 : L'excrétion urinaire

1 min 48 s
Carrying the waste products produced by the cells, the 5 liters of blood in our body pass through the nephrons, small filtration units located in the kidneys, 36 times a day. The waste products isolated in this way are diluted in the water present in our body and evacuated in the urine.
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E21 : La peau

3 min 55 s
An organ of 2 square meters, weighing 5 kg, at the same time flexible, extensible, resistant, and renewing itself every 30 days... Which one is it? The skin, of course! The only organ of our body that we can see and that protects us from radiation, micro-organisms and shocks. Let's travel to the discovery of the three layers that…
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E22 : La respiration cellulaire

4 min 40 s
In a universe that tends towards ever greater disorder, living beings are able to maintain an internal order. To create this order, the cells of an organism carry out a series of chemical reactions: this is called metabolism. This series of chemical reactions, which leads to the degradation of food molecules in the presence of oxygen…
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E23 : Sport et santé

3 min 53 s
L'adage est bien connu : le sport, c'est bon pour la santé ! Alors que nos vies sont de plus en plus sédentaires, maintenir une pratique physique régulière s'avère primordial. On le sait aujourd'hui, mettre le corps en mouvement, c'est agir sur l'ensemble de notre métabolisme.
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E24 : L'alimentation du sportif

5 min 43 s
To practice a physical or sports activity, we know that nutrition is a determining factor. Eating well before and after exercise is essential. But what nutrients does our body need? According to what type of effort? What metabolic mechanisms do they trigger at the level of each of our organs, in our tissues, in our skeleton? To…
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E25 : L'œil et la vision

4 min 11 s
How are images formed in our brain? At the origin, there is light, the one that is sent back to us by the objects that surround us. It enters our eyes through the lens. But how is the light information captured, interpreted and transmitted? And in fact, do we all see the same thing?
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E26 : La réaction inflammatoire

3 min 40 s
The skin and mucous membranes form a physical barrier that effectively protects the body from external aggressions. However, following a trauma or an infection, foreign micro-bodies may manage to penetrate this shield. A complex defense mechanism is then put in place: the inflammatory reaction...
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E27 : La mémoire immunitaire

3 min 49 s
Throughout life, the immune system keeps a memory of past viral or bacterial attacks. Each time a new antigen appears, certain immune cells are responsible for determining its identity card and storing it in anticipation of a future attack. Vaccination relies on this mechanism to stop the most devastating antigens.
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E28 : L'immunité adaptative

6 min 29 s
When viruses and bacteria have succeeded in breaking through the body's first defense barrier (the inflammatory reaction), a second line of defense is put into action: this is adaptive immunity. This second protective shield is specific to vertebrates. It implements a complex mechanism using specific white blood cells: the…
    Levels:
    Élémentaire 5e année Secondaire 10e année 11e année
    Subjects:
    Sciences et technologie Biologie Systèmes vivants
    Skills:
    Apprentissage autonome Pensée critique
    French level:
    B2 : Avancé ou indépendant C1 : Autonome