Common name: Palawan Mangkono
Palawan mangkono is another endemic ironwood species found only in the province of Palawan including nearby islands of Busuanga, Culion, and Manamoc. Its wood is of great interest due to its stiffness and hardness not to mention its heaviness. 

                 _{(no common name)}

This plant species is endemic in Palawan, Philippines and is one of the 370 known species under the genus Tarenna of the family Rubiaceae. A notable feature of this plant is its majestic flower that can be in colors white, green, or yellow. 

Common name: Intoxicating Yam

This yam plant is popular among the natives of Palawan for it is considered as a delicacy. However, this yam plant should undergo various preparations before serving for it contains cyanide toxin. 

Common name: Poonga Oil Tree

This tree can usually be found growing in beach areas. The oil extract from the fruit of this tree is widely used in traditional medications such as in curing ulcers, gonorrhea, vaginal and skin diseases, and for cleaning of teeth and gums. 

Common name: Oriental mangrove

This mangrove species which grows up to 35 meters high is usually found on the seaward side of mangrove swamps, often in the company of Rhizophora. Its bark, when powdered, is used in the processing of a local alcoholic drink in the Philippines called “tuba”.  

Common name: Beach Morning Glory
This plant is a common pantropical creeping vine that grows on the upper parts of beaches and endures salted air. Its leaves are used to hasten the bursting of boils; sap from the young leaves are boiled in coconut juice and used to treat sores and ulcers; and the seeds chewed with areca nut, soothe abdominal pains and cramps. Its leaves when boiled are also used as a traditional treatment against rheumatism. 

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Imbibition refers to the stage where moisture or water enters into a plant seed through the cracks, grooves, or any possible entry within the coat of the seed. The water intake is being absorbed by the tissues within the seed. The rate of water uptake is in relation to two factors namely (1) temperature-dependent; and (2) accompanied by increases in respiration rate and in light sensitivity in some seed species. These observations imply that water uptake during imbibition is an active process at an early stage of this phase. The conclusion of this phase is signaled by an asymptotic approach to a final water uptake, or hydration level, which relies on ambient soil-water potential, soil conductivity to water, seed–soil contact, and seed composition (Hadas, 2005).

The mobilization of seed storage proteins upon seed imbibition and germination is a vital process in the establishment of the seedling. Storage proteins conform compactly, presenting only a limited number of vulnerable sites for initial proteolytic digestion. Evolutionarily related storage proteins have indistinguishable three-dimensional structure, and therefore tend to be initially split at similar sites. The initial cleavage makes possible subsequent rapid and extensive breakdown catalyzed by endo- and exopeptidases. The proteolytic enzymes that degrade the storage proteins during mobilization identified so far are mostly cysteine proteases, but also include serine, aspartic and metalloproteases. Plants often ensure early initiation of storage protein mobilization by depositing active proteases during seed maturation, in the very compartments where storage proteins are sequestered. Various means are used in such cases to prevent proteolytic attack until after imbibition of the seed with water. This constraint, however, is not always enforced as the dry seeds of some plant species contain proteolytic intermediates as a result of limited proteolysis of some storage proteins (Tan-Wilson & Wilson, 2012).

Plants exhibit exquisite sensitivity to their surroundings, possessing a wide array of sensory systems needed to monitor the environment and respond appropriately. It is not surprising therefore to see tropic responses to a host of environmental signals. Thus, plants have been shown to be able to elicit directional growth responses to stimuli from a vast number of abiotic factors (Gilroy, 2008). Two notable plant tropisms, phototropism and gravitropism, will be elucidated below. 

Phototropism, or the differential cell elongation exhibited by a plant organ in response to directional blue light, provides the plant with a means to optimize photosynthetic light capture in the aerial portion and water and nutrient acquisition in the roots. Tremendous advances have been made in understanding of the molecular, biochemical, and cellular bases of phototropism in recent years. Six photoreceptors and their associated signaling pathways have been linked to phototropic responses under various conditions. Primary detection of directional light occurs at the plasma membrane, whereas secondary modulatory photoreception occurs in the cytoplasm and nucleus. Intracellular responses to light cues are processed to regulate cell-to-cell movement of auxin to allow establishment of a trans-organ gradient of the hormone. Photosignaling also impinges on the transcriptional regulation response established as a result of changes in local auxin concentrations  (Liscum et al., 2014). 

Gravitropism is an important plant growth response to the environment that directs shoots upward and roots downward, thereby allowing each organ to reach environments that are adequate for performance of their primary functions. Gravity sensing involves the sedimentation of dense amyloplasts within specialized gravity-sensing cells in each organ. This pathway leads to the development of a lateral gradient of the phytohormone auxin across gravity-stimulated organs. Because auxin promotes cell elongation in shoots and inhibits it in roots, this gradient is responsible for an organ tip curvature that allows it to resume growth at a predefined angle from gravity (Strohm et al., 2013).