Plants and animals (all livings things for that matter) respond to changes in environment. This is one of the criteria for adapting and surviving in a particular environment. Earlier it was thought that plants respond to changes in day length arising from identification of seasonal changes. Certain receptors are present on the leaves which transmitted signals about the duration of the day through the plant. Depending on the day length, the plant would modify its vascular system to various parts exposed to the sunlight including leaves, shot apex, etc.
This would help induce flowering. Long-distance signals travel through the plant which makes adaptations possible. However, scientists from the imperial college of London and a breeding research unit in Cologne have found that certain proteins known as ‘flowering locus T protein’ is present in huge quantities in the leaves and is produced by the FT gene. When the plant is exposed to sunlight, the signals received would travel to various portions of the plant, including the stem, shot apex, etc, activating other genes that enable the plant to flower.
This protein had been linked to a fluorescence dye and has been tracked throughout the vascular system of the plant in response to diurnal changes (Bio Medicine, 2008). An important protective mechanism observed in animals is the flight-fight instinct which is seen in all animals. This permits that the species can survive in a particular environment and can continue their species. When our sense organs obtain sensory information of the presence or approach of a threat (through sight, sounds, smell, etc), the body begins to prepare to face such a threat or flee the sight in order to ensure survival.
Once the brain receives the sensory information, it would process the information and convert it into outputs which could help to protect the species. The brain would utilize several cognitive functions including memory, judgment, perception, experience, etc, to determine the nature, extent and other details of the threat. Accordingly, it would send autonomic and motor signals to other parts of the body to prepare the body to face such a threat.
The adrenal glands would produce more quantities of adrenalin, which would rush to various cells, tissues and organs of the body, increasing activity to meet the energy requirements. The body temperature would rise and the heart would beat faster and with greater force. Breathing would increase to ensure that the increased energy requirements are met. The neuro-hormonal regulation is considered important in preparing the body to face such a threat and continue to survive in the environment (Goligorsky, 2001).
Bio Medicine (2008). Scientists unlock secret of what makes plants flower, Retrieved on August, http://ajprenal.physiology.org/cgi/content/full/280/4/F551.