Biology Chapter on Coordination and Systems

Study Notes

Coordination

Organisms need to detect and respond to changes in their internal and external environments.
Coordination helps all parts of the body work together.
Stimulus: Anything sensed by a neuron is called a stimulus.
Nervous System: Electrical messages (impulses) sent quickly via nerves.
Endocrine System: Chemical messages called hormones travel slowly via bloodstream.

Nervous System

Controls & coordinates all parts of the body.
Central Nervous System (CNS): Brain and spinal cord.
Peripheral Nervous System (PNS): Network of nerves that connect the CNS to the rest of the body.

Vertebrate Sensory Receptors

Detect changes in the environment.

Endocrine System and Hormones

Consists of glands that produce hormones.
Hormones: Chemicals that transfer information around the body.
Hormones control changes in our bodies, like growth and development, water balance, and sexual reproduction.

Diseases

Can be classified based on their causes.
Infectious diseases: Caused by pathogens and can be transmitted.
- Examples: influenza, tuberculosis, tinea.
- Pathogens include bacteria, fungi, viruses, and parasites.
Non-infectious diseases: Cannot be transmitted.
- Genetic: Cystic fibrosis.
- Nutritional: Heart disease.
- Environmental: Lung cancer.
- Physiological malfunction: Shortsightedness.

Atoms and Elements

Microscopic particles that make up all matter.
Composed of protons (p+), neutrons (n), and electrons (e-).
In a neutral atom: Atomic number = number of protons = number of electrons.
Mass number: Total number of protons and neutrons in the nucleus.

Structure of the Periodic Table

There are about 118 elements, 92 naturally occurring.
Arranged by atomic number (number of protons).
Reactivity:
- Most reactive elements are on the left side.
- Transition metals in the center.
- Least reactive elements are on the right side.

Radioactivity

Most nuclei are stable, but some are unstable and spontaneously decay, emitting radiation.
Neutrons play a key role in stabilizing the nucleus.
Nuclei with too many or too few neutrons tend to decay.

Chemical Reactions

When atoms react to form compounds, it's the electrons in the outer shell that determine the type of reaction.
Example: Sodium + chlorine = sodium chloride (Na + Cl = NaCl)

Description

Explore the critical roles of the nervous and endocrine systems in coordinating responses in organisms. This quiz covers stimuli, sensory receptors, and hormonal functions crucial for growth and development. Test your understanding of how the body manages internal and external changes effectively.