Questions-réponses.

https://cytobase.montp.inserm.fr/Cours/Apoptose.html

(Note : This process can be compared to a behaviour previously mentioned in animals: for example, a sick ant will isolate itself to die in order to protect the colony [ [02-ethiq Evol/F385-07b]]):

The immune system and cancer : The immune system does not react against cancer cells because they are not recognised as foreign. They thus evade detection and elimination by the immune system.

Can cancer be cured spontaneously ? In very rare cases, cancer may shrink or disappear without treatment. This phenomenon is known as spontaneous cancer regression or spontaneous remission. Certain cancers, such as melanoma, kidney cancer and liver cancer, have occasionally been known to regress spontaneously. These cases are exceptional and poorly understood. They account for fewer than 1 in every 60,000 to 100,000 cancer cases. However, even in the event of regression, monitoring remains necessary, as the disease may recur.

Intravesical immunotherapy with Calmette-Guérin bacillus (BCG) :
BCG is usually used for vaccination against tuberculosis. Research dating back to 1975 has shown its usefulness in the treatment of superficial bladder cancers to prevent or delay recurrences. Its mechanism of action within the bladder is not fully understood. BCG is thought to stimulate the immune system and the bladder wall, which may then be able to reject tumour cells.
https://www.arcagy.org/infocancer/localisations/rein-et-voies-urinaires/cancer-vessie/traitements/l-immunotherapie.html/

A cultural ideology is a system of shared ideas that influence the construction of national identity, the perception of history and the transmission of values within a society.

Animal species : In 2026, the number of known species on Earth is estimated at around 1.5 million scientifically described species. However, the total number of species (both known and yet to be discovered) is much higher.
The most numerous species are insects (around 1 million described species) and microorganisms.

Estimates vary considerably depending on the source :
5 to 10 million species in total (according to studies such as the Global Biodiversity Assessment).
Some estimates go as high as 1 trillion (1,000 billion) species if microorganisms (bacteria, archaea, etc.) are included.

The CNRS, through its researchers and partnerships (such as PatriNat with the MNHN and the OFB), draws on recognised international studies. The estimate most frequently cited and adopted by the scientific community, including in France, is the one published in PLoS Biology: there are thought to be around 8.7 million species living on Earth, of which:
6.5 million terrestrial species,
2.2 million marine species.
This estimate has been widely reported and used in the work of the CNRS and its partners, particularly to highlight the small percentage of species that have already been described and catalogued.

1 – The skin barrier:
It consists of a mixture of sebum (produced by the sebaceous glands) and sweat, forming a protective film on the skin’s surface.
Role:
- Limits water loss.
- Prevents the penetration of microorganisms and irritants.
- Maintains a slightly acidic pH (around 5.5), which is unfavourable to pathogenic bacteria.

2 – The stratum corneum:
This is the outermost layer of the epidermis, composed of dead cells (keratinocytes) and intercellular lipids.
Role:
- Physically blocks pathogens and toxins.
- Limits dehydration.
It is constantly shed (in a cycle of approximately 28 days).
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The success of Rome’s territorial expansion was based on an innovative political strategy : a policy of alliance and integration. Rather than subjugating defeated peoples by force, Rome granted them various statuses allowing them to retain partial autonomy in exchange for a military contribution. This system, known as the ius Latii, transformed former enemies into a source of soldiers and loyalty, multiplying Roman power without the need to maintain a costly occupying army.
The Roman military machine

Roman expansion was no accident: it was underpinned by a formidably effective army. The Roman legion, the army’s basic unit, was distinguished by its discipline, its capacity for tactical adaptation and its military engineering prowess—the construction of roads, fortified camps and siege bridges. Following the reforms of Marius (107 BC), the army became professional: soldiers served for a fixed term, received a pay and, upon discharge, were granted land, which bound them as much to their generals as to Rome.

The height of the empire : a world empire
This power was not limited to military strength alone. Rome built a network of 80,000 kilometres of paved roads that enabled the movement of legions, merchants and civil servants. It imposed Latin as the administrative language in the West and spread Roman law, urban planning, architecture and religious practices — creating a shared civilisation that historians refer to as ‘romanitas’. Trade extended as far as India and China via the Silk Road, making the Roman Empire one of the first quasi-global economic systems of the ancient world.
https://citopendia.fr/comment-rome-est-elle-devenue-un-empire-mondial/

ius Latii:
The ius Latii (or Latin law) was a legal status granted in ancient Rome to certain cities or individuals, conferring upon them rights that fell between those of Roman citizens and those of foreigners. This status notably allowed them to trade with Rome, enter into legal marriages and enjoy partial legal protection, without, however, granting full Roman citizenship.

This right was often granted as a collective or individual reward. It evolved over time, particularly following the reforms of Julius Caesar and Augustus, who gradually extended Roman citizenship to ever-larger sections of the population.

The Viking invasions spanned a broad period, generally considered to be between 793 and 1066, with distinct phases:
1. Beginning of the raids (late 8th – early 9th century)

793: First documented Viking raid in England, on the monastery of Lindisfarne (June 7, 793). This event is traditionally considered the beginning of the Viking invasions in Europe. Source: History of the Vikings – Lindisfarne 793
795: Attack on the monastery of Iona (Scotland).
800–850: Intensification of raids in England, Ireland, Francia (present-day France), and Frisia (the Netherlands).

2. Settlement and Establishment of Territories (9th century)

840–870: The Vikings establish a permanent presence in England (e.g., the Kingdom of Danelaw, established in 886 by the Treaty of Wedmore between Alfred the Great and Guthrum).
850–900: Founding of Dublin (Ireland) around 841 and development of trading posts.
860–870: Raids in Francia (e.g., the siege of Paris in 885–886 by the Vikings led by Sigfred and Rollo).

3. Expansion and Heyday (10th century)

911: The Treaty of Saint-Clair-sur-Epte (August 10, 911) ceded Neustria (future Normandy) to Rollo, a Viking chieftain, in exchange for his conversion to Christianity and his loyalty to the King of West Francia (Charles the Simple).
980–1015: Sven Forkbeard and his son Canute the Great extended their rule over England, Denmark, and Norway.
1000–1030: The Vikings controlled territories in England (Canute’s kingdom), Ireland, Scotland, and Russia (founding of Novgorod and Kiev by the Varangians).

4. End of the Invasions (11th century)

1066:
September 25: The Vikings are defeated at the Battle of Stamford Bridge (England) by King Harold Godwinson. This battle is traditionally considered to mark the end of the Viking invasions of England.
September 28: William the Conqueror (a descendant of the Vikings of Normandy) lands in England, marking the beginning of Norman rule.
1070: Last documented Viking raids in England and Scotland.