Ap Psych Biology

Axon

Axon

the long, tube-like structure that carries the neural message to other cells

Central nervous system

part of the nervous system consisting of the brain and spinal cord

Cerebral cortex

the intricate fabric of interconnected neural cells that covers the cerebral hemispheres; the body's ultimate control and information-processing center

Dendrites

branch-like structures that receive messages from other neurons

Peripheral nervous system

all nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself - divided into the: § somatic nervous system § autonomic nervous system

Synapse

microscopic fluid-filled space between the rounded areas on the end of the axon terminals of one cell and the dendrites or surface of the next cell

Thalamus

part of the limbic system located in the center of the brain

Autonomic Nervous system

division of the PNS consisting of nerves that control all of the involuntary muscles, organs, and glands; sensory pathway nerves coming from the sensory organs to the CNS consisting of sensory neurons

Gene

A segment of DNA on a chromosome that codes for a specific trait

Hypothalamus

a small structure in the brain located below the thalamus and directly above the pituitary gland

Neurons

the basic cell that makes up the nervous system and receives and sends messages within that system

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, these travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

Sympathetic Nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations. Fight or flight.

Action potential

a neural impulse; a brief electrical charge that travels down an axon

Cerebellum

A large structure of the hindbrain that controls fine motor skills.

Hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Limbic system

A doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres; associated with emotions such as fear and aggression and drives such as those for food and sex. Includes the hippocampus, amygdala, and hypothalamus.

Parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy. Rest and digest

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

Chromosomes

threadlike structures made of DNA molecules that contain the genes

Corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

Myelin Sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, this regulates growth and controls other endocrine glands.

Endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles

Medulla

an extension of the spinal cord into the skull that coordinates heart rate, circulation, and respiration

Sensory Neuron

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

Cell body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

Frontal lobes

the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments

Glial cells

cells in the nervous system that support, nourish, and protect neurons

Positron emission tomography (PET)

a method of brain imaging that assesses metabolic activity by using a radioactive substance injected into the bloodstream

Electroencephalogram (EEG)

An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.

Endorphins

"morphine within"—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Magnetic Resonance imaging (MRI)

brain-imaging method using radio waves and magnetic fields of the body to produce detailed images of the brain

Occipital lobes

portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

Parietal lobes

portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

Temporal lobes

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

Heritability

The proportion of variation among individuals that we can attribute to genes. The heritability of a trait may vary, depending on the range of populations and environments studied.

Amygdala

two lima bean-sized neural clusters in the limbic system; linked to emotion.

Hippocampus

A neural center located in the limbic system that helps process explicit memories for storage.

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

Reticular Formations

Basic functions; alertness, sleeping patterns, wakefulness

Behavioral genetics

study of hereditary influences and how it influences behavior and thinking

natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

Pons

A brain structure that relays information from the cerebellum to the rest of the brain

Resting potential

the state of the neuron when not firing a neural impulse

Basilar membrane

A structure that runs the length of the cochlea in the inner ear and holds the auditory receptors, called hair cells.

midbrain

A small part of the brain above the pons that integrates sensory information and relays it upward.

motor neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

receptors

parts of the cell membrane that receive the neurotransmitter and initiate or prevent a new electric signal

Association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

Eardrum

a thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate

identical twins

twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

All or none law

principle that the action potential in a neuron does not vary in strength; the neuron either fires at full strength or it does not fire at all

CT (computed tomography) scan

a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Also called CAT scan.

Deoxyribonucleic acid (DNA)

A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.

Fraternal twins

twins who develop from separate fertilized eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment.

Functional magnetic resonance imaging (MRI)

A computerized image of the activity levels of various areas in the brain generated by detecting the amount of oxygen brought to each area

Genotype

An organism's genetic makeup, or allele combinations.

Hindbrain

An area of the brain that coordinates information coming into and out of the spinal cord

Phenotype

An organism's physical appearance, or visible traits.

Acetylcholine (Ach)

A neurotransmitter that enables learning and memory and also triggers muscle contraction

Forebrain

The largest and most complicated region of the brain, including the thalamus, hypothalamus, limbic system, and cerebrum.

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements

Spinal cord

Nerves that run up and down the length of the back and transmit most messages between the body and brain