Has a direct relation to the nervous system, fast-acting (can happen in milliseconds or seconds), but has a short-term effect
Chemical Control
Includes endocrine system, has a variety of hormones (controls how our body responds to the different stimuli present in our environment), slow-acting compared to Nervous Control (can happen in minutes, hours, or days), but has a long-term effect
Plants do not have a nervous system, they can't feel pain (they don't have pain receptors) and can't think (they don't have a brain)
But plants can recognize their environment and coordinate their behavior, they can respond against these environmental changes with the help of hormones
Nervous System
Responsible for coordinating the functions of our body (chewing, digestion, etc.)
Endocrine System
Responsible for the attainment of homeostasis or internal balance
Brain
Is the main organ used by vertebrates for nervous control
Nerve Nets
Simple kind of nervous system that some invertebrates have, scattered throughout the body of the animal, allows for simple behavior or movements like contractions
Animals have nerves that carry information from the brain and spinal cord to the muscles and glands, the transmission of nerve cells just happens in milliseconds
Dendrites
Branches of Soma (cell body), main function is to receive electrochemical signals from the neighboring nerve cells
Axon
The longest part of the nerve cell, main goal is to transmit the electrochemical signals to the other neighboring nerve cells
Axon Terminals
Its main goal is to pass these signals to the other nerve cells until the message will reach the brain
Human Nervous System
Has 2 parts
Plants also process information from their environment and change their growth based on that information, they can identify if there's an increase in the temperature or change in the season
Action Potentials
Although they don't have nerves, plants cells are capable of generating electrical impulses called
Circadian Rhythms
Plants have all kinds of movement based on their circadian rhythms (these are the physical, mental, or behavioral changes that an organism experiences over a 24-hour cycle)
Endocrine Glands and Organs
Hypothalamus
Pituitary gland
Pineal gland
Thymus
Thyroid and Parathyroid glands
Pancreas
Adrenal glands
Testicle (in male)
Ovary (in female)
Placenta (during pregnancy)
Hypothalamus
Called the "Master gland" as it can control the other glands present in the body
Pituitary Gland
Controls the growth or development of a person, and releases oxytocin (love hormone), which is a human hormone that stimulate uterine contractions and is important for females during labor
Pineal Gland
Controls the production of melatonin
Some Human Hormones
Growth Hormone (Stimulates cell division and growth)
Oxytocin (Stimulate uterine contractions)
Insulin (Stimulates decrease in blood sugar levels)
Estrogen (Stimulates development of female reproductive system)
Testosterone (Stimulates development of male reproductive system)
Plant Hormones
Plants have simpler hormones compared to animals, but these hormones influence the growth and development of plants
Auxin
Builds up on the shaded side of the plant & stimulates growth beneath the tip, the cells on the shaded side are exposed to more auxin; they grow more than the side exposed to the light
Gibberellin
Promotes fruit growth, elongation of shoots, and breaking the dormancy in seeds and buds, it is present during the early stages of plants
Cytokinin
A plant hormone that stimulates cell division to grow roots, fruits, and branches, it is produced in the middle to the adult stage of plants
Stages of the Sensory & Motor Mechanism
1. Stimulus
2. Receptor
3. Sensory Neurons
4. Control Center
5. Effector
Tropism
A change in a plant's growth in response to external stimuli
Positive Tropism
Growth is towards the stimulus/the growth of the plant follows the stimulus
Negative Tropism
Growth is away from the stimulus/the growth of the plant will be opposite from the direction of the stimulus
Phototropism
Movement of the plant in response to light, usually in the direction toward the light
Geotropism
Movement of the plant in response to gravitational force
Positive Geotropism
Growth follows the direction of the gravitational force (downward)
Negative Geotropism
Growth is in contrast with the direction of the gravitational force
Hydrotropism
Movement of the plant in response to water
Positive Hydrotropism
The root grows towards water
Negative Hydrotropism
Exhibited by the shoots, because they don't need to collect water, they need to collect light
Thigmotropism
Growth in response to touch or contact with a solid object
Positive Thigmotropism
Demonstrated by climbing plants or vines, which have specialized structures called tendrils (which tend to grow in response to the solid object where they're attached to)
Nastic Movements
Plant movements that occur in response to environmental stimuli
Photonasty
Movement referring to the amount of light intensity