top of page
Generally a plants physiology is based around: photosynthesis, respiration, plant hormone functions, tropisms, nastic movements, photoperiodism, circadian rhythms, seed germination, dormancy, stomata function and transpiration.
Cellular Respiration: This is the metabolic reactions and process that take place in the cells of the plant to create energy from nutrients into ATP (an energy molecule) then release waste products. Basically, nutrient molecules are broken down into smaller molecules and release ATP. These are most of the time exothermic, as they produce heat as they break down the nutrients.
Plant Hormones: These are the signal molecules that are produced within the plant. These hormones occur in very low concentrations. Hormones differentiate the shape or form of the stems, leaves, flowers, as well as the formation and the ripening of the fruit.
Tropism: This is a direct response to anything the plant is around. The four main stimuli for plants are light, gravity, touch and water. An example of the light would be like the phototropism experiment that you probably did in 3rd+ grade, example on the right→. Gravity would be how the plant reacts to the gravity, such as some vines grow against gravity (negative), while some fall with it (positive). The plants touch response is basically how sensitive it is to foreign pressure. Take a Venus Fly Trap, they have around six "trigger hairs" that send a signal to change the water pressure so that the leaves can close. Most plants don't have too much in the touch department, but it doesn't mean that they don't have anything. Water intake is crucial to any living organism on earth. In hydrotropism, the roots of the plant grow toward or away from the water source. This is why you can see a lot of roots along a eroded bank of a pond or stream.
Nastic Movements: In nastic movements, the direction of movement is determined by the anatomy of the plant rather than by the position of the origin of the stimulus.
Photoperiodism: This is one of a plants sense to detect seasonal changes of the air. That helps them with their blooming cycle, allowing them to bloom at the right time during the day to absorb sunlight and control their internal clock. For more in depth explanation, visit Photoperiodism.
Circadian Rhythms: With an internal clock that all plants have, they can differentiate their day movements from their night movements. During the day, plants want to get all of the sunlight that they can, so they either face themselves in that direction or open the leaves to get more surface area.
Seed Germination: Germination is the process of when the plant grows from the seed. Factors that could influence the growth of the sprout are temperature, water availability, and how much soil is on top of the seed. Theses all serve an important role in a growing seed.
Dormancy: The state in which a plant or plant part exhibits little or no growth and in which most, if not all, metabolic activity ceases for a period of time. Read More Here
Stomata: These are the little diaphragm of the plants, like humans how the diaphragm regulates air movement into the lungs. Yet plants don't have lungs, they have pockets that take carbon dioxide in to convert it into oxygen.
Transpiration: Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
bottom of page