The towering Himalayas served as a significant physical barrier that shielded India from foreign invasions from the north. This mountain range, with its high peaks and difficult terrain, made it challenging for invading armies to penetrate into the Indian subcontinent. Additionally, the harsh climate and altitude deterred many would-be conquerors, allowing India to maintain a degree of isolation from northern threats.
See Boxer Rebellion.
It started as the militia to protect the citizens of foreign invasion.
the invasion of France by several foreign armies
From Augustus' time, the legions were located in the border provinces to protect the empire from foreign invasion.
One of japans natural barriers is that japan is very mountainous. This could also be good for japan in case of a foreign invasion.
The epidermis is composed of multiple layers of tightly packed epithelial cells that act as a physical barrier against the entry of bacteria and other foreign agents into the body. Additionally, it contains specialized cells like Langerhans cells that contribute to the immune response by detecting and responding to foreign invaders.
The Foreign Invasion - 1912 was released on: USA: 20 July 1912
immune
immune system
hot sands protected egypt and nubia from foriegn attacks
Swamp Wars - 2011 Foreign Invasion 3-6 was released on: USA: May 2013
Colonise or invasion.
See Boxer Rebellion.
Intact skin provides a vital physical barrier for the body against antigens (foreign invaders). Additionally, its mildly acidic environment is hostile to pathogens. Established bacterial colonies also help to out compete foreign strains of bacteria.
A response of the body to an invasion of foreign substances is inflammation. The immune system will also produce more white blood cells and send them to the site of the infection.
Color change in response to temperature would not help prevent pollination by a foreign species, as color is typically not a barrier to pollination. Other mechanisms such as physical barriers, timing of flowering, or chemical signals are more effective at preventing pollination by foreign species.
No natural barrier completely protected Egypt from invasion as all of these difficulties were eventually overcome, but some of the natural barriers that substantially minimized foreign invasions were: the Sahara Desert, the Red Sea, the Sinai Desert, and the Mediterranean Sea. (Amphibious assaults were usually not terribly successful at this period.)