AP Psychology Chapter 3, part 3

Dominant gene

A dominant gene is a segment of DNA information that is used to make chromosomes. Dominant genes are a result of dominant alleles in chromosomes. When an allele is dominant it is expressed in the phenotype over a recessive allele. The phenotype is what chromosome is present in the organism. So a person with a dominant allele for brown hair and a recessive allele for red hair (this combination is identified in genetic notation as "Br") will have brown hair

Hormones

A hormone is something produced in the body that circulates in the bloodstream and then influences the activity of living cells that are far from where it was produced. Because hormones travel to their target tissue, they are sometimes referred to as signaling molecules. For example, estrogen is produced by the ovaries, but effects the functioning of cells in the heart, uterus, breast, liver, and brain. Any molecule produced in the body that travels to another tissue via the bloodstream for its effect is classified as a hormone.

Frontal lobe

A region of the cerebral cortex at the front of the brain (lying just behind the forehead) that is necessary for motor control and more complex, high-end functioning like speech, decision making, and judgments.

Polygenic traits

A trait which is identified by a multitude of genes instead of only one.

Mirror neurons

Mirror neurons are a type of brain cell that fires when you do an action, and also when you simply watch someone else doing the same action.

Broca's area

Named for the French surgeon and anthropologist, Paul Broca, who found this area of the brain, Broca's Area is located in the frontal lobe of the brain and acts as the speech center. Although there are other areas of the brain that also influence speech (Wernicke's Area and the motor cortex), Broca's Area is considered the central component.

Neurogenesis

Neurogenesis refers to the process by which neurons or nerve cells are generated in the brain. Neurogenesis is most active during prenatal development, when a baby's brain is being formed.

Oxytocin

Oxytocin is a powerful hormone that acts as a neurotransmitter in the brain. It regulates social interaction and sexual reproduction, playing a role in behaviors from maternal-infant bonding and milk release to empathy, generosity, and orgasm. When we hug or kiss a loved one, oxytocin levels increase; hence, oxytocin is often called "the love hormone." In fact, the hormone plays a huge role in all pair bonding

Phenotype

Phenotype refers to the visible expression of the information contained in a person's genetic code (known as genotype). This includes whatever can be measured or observed of a person's physical, psychological and biological makeup.

Split-brain surgery

Split-brain surgery, or corpus calloscotomy, is a drastic way of alleviating epileptic seizures, the occurrence of sporadic electrical storms in the brain. The procedure involves severing the corpus callosum, the main bond between the brain's left and right hemispheres. After a split-brain surgery the two hemispheres do not exchange information as efficiently as before. This impairment can result in split-brain syndrome, a condition where the separation of the hemispheres affects behavior and agency.

Temporal lobe

The area in the brain involved with hearing. The temporal lobes are part of the cerebral cortex and are located above the ears. Interestingly, each lobe is responsible for hearing in the opposite ear -- so the lobe on the left side of your brain is responsible for hearing from the right ear.

Endocrine system

The endocrine system consists of a series of glands that produce chemical substances known as hormones ([link]). Like neurotransmitters, hormones are chemical messengers that must bind to a receptor in order to send their signal. However, unlike neurotransmitters, which are released in close proximity to cells with their receptors, hormones are secreted into the bloodstream and travel throughout the body, affecting any cells that contain receptors for them.

Heterozygous condition

The situation that occurs when two genes in a specific pair are different.

Homozygous condition

The situation that occurs when two genes in a specific pair are the same.

Chromosomes

The threadlike structures made of DNA molecules that contain the genes. A human cell has twenty-three pairs of chromosomes, one member of each pair coming from each parent. It is these cells that are so important in determining who we are from a genetic standpoint.

Genotype

The total set of genes contained within an organisms cells. Organisms contain some genes that are expressed (you can consider the "expressed" to mean that the gene is active or being used) and some that are not. Regardless, all the genes an organism has are considered the genotype

Corpus callosum

This area contains the largest bundle of nerve fibers in the brain and connects the two sides (hemispheres) of the brain. The corpus callosum doesn't just sit there, it is responsible for allowing the two hemispheres to communicate with each other and share information. Thus, the corpus callosum carries massages between the left and right hemispheres of the brain.

Wernicke's Area

Wernicke's area is the region of the brain that is important for language development. The Wernicke's area is located in the temporal lobe on the left side of the brain and is responsible for the comprehension of speech.

Zygote

When a female (human) egg is fertilized, it is no longer classified simply as an egg, but is now considered a zygote. For two weeks, the zygote goes through an amazing amount of development that occurs in the form of cell division.