Some of the genes controlling our characteristics are dominant while others are recessive.

* dominance is a relationship between genes in genetics, in which one gene suppresses the characteristics controlled by the other. It is the stronger, more powerful of the two types.

* recessive gene will nto be able to exert any influence on a characteristic if it is paired with a dominant gene. 

* each individual has two genes that determine each genetic trait - one gene from each parent

* a trait carried on a dominant gene is called a dominant trait, and a trait on a recessive gene is called a recessive trait.

* pairs of genes can be dominant gene-dominant gene, dominant gene-recessive gene, or recessive gene-recessive gene pairs.

* when a dominant gene comes from one or both parents, offspring usually inherit the same genetic trait. A trait carried on a dominant gene will always be expressed regardless of what type of gene it is paired with.

* Someone who inherits a dominant gene-recessive gene pair is called a carrier. Carriers can pass on a dominant gene or a recessive gene to their offspring.

- brown hair is a dominant gene trait, and most children with brown haired parents have brown hair, unless both parents pass down a recessive gene such as blonde hair

- brown eyes are a dominant gene trait, and most children with brown-eyed parents have brown eyes, unless both parents pass down a recessive gene such as blue eyes

- in order to have blonde hair or blue eyes, the child would have to have the blonde haired or blue-eyed gene from both parents - not just one

* recessive genes are generally not expressed when paired with a dominant gene and can only be expressed as a characteristic of the individual if the individual inherited a recessive-recessive gene pair. 

* Someone who inherits a dominant gene-recessive gene pair is called a carrier.

All of the chromosomes except for the sex chromosomes. There are 22 pairs. They carry genetic material that controls all of our characteristics with the exception of biological sex. They are the same pairs in males and females. 

* any chromosome that is not an allosome (sex chromosome)

* may be liver, brain, or tissue cells - as long as they don't relate to reproduction

The two chromosomes(X and Y) of the 23rd pair that carry the blueprint for the offspring’s biological sex. A female has an XX pair and a male has an XY pair of sex chromosomes.

Biological parents pass on one set of 23 chromosomes in each sperm cell or ovum. The mother can only pass on an X sex chromosome since she has an XX pair, but the father can pass on either an X or a Y chromosome in each sperm cell. The biologocal father's sperm cell therefore determines the sex of the offspring.

Name used for the fertilized ovum when it is still only one cell.

It is when the sperm cell of the biological father penetrates and fertilizes an ovum (egg cell) from the biological mother, conception occurs, and the new cell that is formed is called a zygote.

THe zygote contains the 23 pairs of chromosomes that control its maturation. The zygote will develop into a female unless there is a Y sex chromosome present. A gene on the Y chromosome causes the fertilized cell to differentiate into a male.

The term used for the traits that are actually expressed in the individual rather than the sum total of inherited genetic material

- the observable characteristics of an organism due to inheritance

e.g. when the shape of a child's nose resembles that of a parent

A trait that is carried by a gene on a sex chromosome(X and Y) that only appears in the absence of the gene for the dominant trait. Someone who has this trait did not inherit the dominant gene

Ex. Color blindness is carried on a recessive gene on the X chromosome. A male who inherits this recessive gene will be color blind because it is impossible for him to also have a dominant gene on a second X chromosome to repress the recessive trait. Females who are color blind have a recessive-recessive gene pair. Hemophilia is also carried the same way as color blindness.

The physiological system of the body that contains glands which secrete hormones to stimulate growth and control the physiological functions of the body.

It is the system of the body responsible for managing hormone levels in the blood stream. It consists of a number of glands.

Called the “master gland,” this gland controls other glands in the endocrine system and secretes growth hormone(GH)

* It causes other glands to secrete hormones. 

* the most important of human endocrine glands

* directly controls the activity of many other glands in the system

* nestled just under the brain

* secretes massive amounts and varieties of hormones

* It is controlled by the hypothalamus of the brain. 

The hormone secreted by the pituitary gland which stimulates physical growth and development. In the absence of GH, an infant will not develop to normal height. Actually, children do not grow taller than four feet. GH also stimulates the adolescent growth spurt.

The thyroid gland also controls physical growth and development and development of the nervous system. It secretes the hormone thyroxin. Without adequate levels of thyroxin, infants become mentally retarded. Early treatment is effective and children who develop a thyroxin deficiency after brain maturation is completed have stunted physical growth but no intellectual disability (mental retardation).

Male sex hormones that control the development of sex organs as well as secondary sex characteristics. 

In adolescence, the increase in androgen levels in the blood causes a rapid growth spurt and growth of male sex organs.

One of the female sex hormones secreted by the ovaries which directs the development of the female reproductive during prenatal development and during puberty, and also stimulates the release of growth hormone

In females, the ovaries secrete an increased amount of estrogen which in turn triggers the production of GH and leads to the female adolescent growth spurt. The hormone secretions during the growth spurt stimulate the development of the breasts, pubic hair, uterus, and vagina. They also trigger an increase in fat storage. 

A hormone secreted by the adrenal gland which is responsible for the body’s flight or fight response. Adrenalin helps the body prepare to respond to danger

Blood flow shifts from the core of the body to the extremities. There is a decrease in blood pressure and an increase in heart rate. These are all autonomic reactions to get the body ready for action. 

The body responds the same way to stress as it does to a real physical threat. The long-term effect of high cortisol levels in the blood is reduced immune response.

Adrenalin passes through the placenta barrier and enters the bloodstream of the fetus. Adrenalin increases the motor activity of the fetus and increases fetal heart rate. If this occurs over an extended period of time it can cause stunted prenatal growth, low birth weight, or birth complications.

A substance that can pass from a pregnant mother to the fetus through the placenta and cause abnormalities.

Ex. maternal diseases, diet, drug use (including alcohol and nicotine), exposure to X-rays, and other environmental influences.

The fetus is generally not affected by a teratogen if exposure occurs during the first or third trimester. Because so many vital organs and body parts are developing during the embryo stage or second trimester, harmful agents are especially dangerous during this prenatal period. This is often referred to as a critical period in prenatal development.

A test used to screen for genetic defects and chromosomal abnormalities in a fetus. The test involves removing amniotic fluid from the amniotic sac in the uterus, testing the fetal cells for indicators of genetic abnormalities.

* involves testing fluid from the "sac" containing the fetus

The disadvantage of this technique is that it cannot be done until the 16th week of pregnancy. 

The term used to describe the fact that the left and right hemispheres of the brain control different functions. For example, the language center is located in the left cerebral hemisphere

Newborns show brain lateralization. For instance, most newborns show a preference for grasping objects with their right hand rather than their left. However, lateralization strengthens with age. The presence of handedness in newborns has led some people to suggest that handedness is genetically controlled.

The end of sexual reproductive capacity. In women this is referred to as menopause

It typically spans a 10-year period and usually begins in a woman's early fifties. A drop in estrogen levels in the body triggers the climacteric. Lowered levels of estrogen in the body cause changes in the fenale's sex organs. Organs shrink and genitals react more slowly to stimulation. The vagina secretes fewer lubricants during arousal. The body also loses the protections afforded by estrogen. Estrogen helps protect against plaque build-up on the walls of arteries and helps maintain good bone nass density. Lowered levels of estrogen are also associated with mood fluctuations, hot flashes, and night sweats. 

* one of two or more forms of a gene (the genetic code that represents a specified trait)

- each chromosome is part of a pair, so the allele, or trait, is present in the same spot on the pair of chromosomes

* potentially serious birth complication caused by reduced oxygen flow to the fetus during birth. Oxygen deprivation can be due to a build-up of mucous in the throat of the baby or a crimp in the umbilical cord. The hard to the baby from anoxia depends on the degree and length of time of the oxgen deprivation. Medications taken by the mother to redue pain during labor and delivery generally slow dow the birth process and also increase the risk of harm to the fetus.

* can cause brain damage and other defects

* affects 1% of babies

* usually occurs when the umbilical cord becomes tangled or constricted during childbirth

* located at the very base of the brain, the very lowest structure is the medulla

* acts like the spinal cord (its major functions involve involuntary reflexes)

* describes one of the two patterns of development (the other being the Proximodistal Principal)

* asserts that growth progresses from head to foot (as opposed to from near to far) direction of motor development

That is, children tend to gain control over the upper portions of their bodies before the lower part. (they can reach and grasp before they can walk).

* utilizes the process of mitosis, which replicates a genetic code into different cells

* the sheep Dolly is famous for being cloned

* occurs when a father's sperm cell joins with a mother's egg cell 

- the female egg (ovum) is released by the female

- the male sperm penetrates the egg

- a zygote (fertilized egg) is created

* the period of the embryo lasts from the time of the zygote's attachment to the uterine wall until the first occurrence of bone development

* a unique molecule (sometimes called the essence of life) that is contained in every cell of every living plant or animal

* is present in each one of the body's approximately 60 trillion cells

* enables cells to copy themselves

* can help determine the biology and heritage of a child, since each individual has DNA cells from both parents

* Is caused by having three rather than two chromosomes at the 21st chromosome position.

* congenital disorder that causes mild to severe mental retardation, slow physical development, and characteristic physical features

* is caused by an extra chromosome

* occurs in roughly 1 out of every 1,000 births

* results in greater susceptibility to childhood illness, leukemia, respiratory, and/or heart problems

* a state of tension resulting from a need that arouses and directs an organism's behavior

* a state of activation that occurs as a response to a need or desire for something

* a pattern of mental and physical defects in a fetus that are associated with high levels of alcohol consumption during pregnancy

* scientific research shows that alcohol use by pregnant women can result in:

- birth defects in unborn children

- low birth rate

- facial abnormalities (sjort nose, thin upper lop, widely spaced eyes, small head)

- heart problems

- poor academic performance during childhood (intellectual disability)

- a smaller than average brain

* occurs at a rate of between 1 and 3 per 1000 births

* Native-American women are the most vulnerable to the effects of alcohol, and to having children with Fetal Alcohol Syndrome

* triggered by maternal smoking while pregnant

* may result in birth defects such as:

- facial abnormalities

- mental retardation

- heart defects

- a host of other problems

* the smallest functional unit for the transmission of a hereditary trait, carrying biological patterns (such as facial features, height, and body type) from both parents to a child

* a section of the genetic code of a living thing

* present within all living things

* the artificial manipulation, building, replacement, or alteration of genes outside of normal breeding

* allows researchers to perform such feats as placing rat genes into a mouse, resulting in an abnormally large rat

* aims to create specific characteristics that may not normally be present in a person, animal, or thing

a period of rapid physical growth

* occur most dramatically during two periods of life:

- birth to age three

- adolescence

* growth in  years between these two growth spurts is moderately slow

Environmental influences like poor nutrition or hormonal abnormalities can stunt the physical growth of the child. Their is also a syndrome called failure to thrive that affects an infant's physical growth.

* a sex-linked disorder controlled by a gene carried on the sex-determining chromosome

- e.g. color blindness (which affects only boys)

* disease that can be passed from mother to newborn in the birthing process, if the mother is in an active stage of the disease

* can attack the skin or mucous membranes

* is often difficult to treat

- women who know they are in an active stage of Herpes often deliver children through cesarean section rather than vaginally, as a preventative measure

HIV or AIDS

* sexually transmitted disease that causes the human immune systen to fail and is usually lethal

- the HIV/AIDS virus may enter the bloodstream of the unborn infant of an infected mother by crossing the placental barrier

* babies born with HIV/AIS often die during infancy or early childhood

* chemicals secreted by the endocrine glands and carried throughout the bloodstream

- the brain and automatic nervous system control the endocrine system's glands

* have a high correlation in IQ scores

* average correlation is .85

* signals from the (inside) physiological aspect of an individual that indicate something is desired as a result of a physical need

- e.g. the desire for food

* affects children who are not given adequate amounts of healthy food, or receive food that is nutritionally deficient

* may result in physical, mental, or emotional traumas

* common in Third Word countries

* processes of biological development of behavior-related bodily mechamisms

* pre-programmed, natural changes in the body

* occurs when internal clocks signal to the body that certain developments should occur

* is exemplified by the changes in height, weight, and sexual development that takes place during puberty

* focuses on the unfolding of genetically-determined developmental sequences

* special type of cell division necessary for sexual reproduction in eukaryotes

- eukaryotes are organisms whose cells contain complex structures enclosed within membranes

* reduces the number of chromosomes in reproductive cells, leading to the production of gametes

* without meiosis, sperm and egg cells would have the same number of chromosomes as body sells

- normal human cells (non-sex cells) have 23 pairs of chromosomes, making 46 total

- sex cells have 23 single chromosomes

- when male and female sex cells join, they form 23 pairs, or 46 chromosomes

* scientific theory of how hereditary characteristics are passed from parent organisms to their offspring

* explains the fundamental laws of genetic inheritance

Estrogen and progesterone control the menstrual cycle in females.

* the shedding of the female uterine lining which occurs on a regular basis as girls reacy sexual maturation

* the process that allows girls to become pregnant

- an egg is released each month during the cycle, which, if fertilized by a male sperm, could create a child

* largely a function of maturation

- a result of nature rather than nurture

* differs widely between children and adults

* a biologically-based process or funciton of maturation

- parental involvement has little to do with it

* the hereditary component of development

- may include physical, mental, and emotional traits

* a biological essential resulting from deprivation

* needs refer to biological necessities, not something the mind desires or craves

* the sense of smell

* well-developed within a newborn

- a baby's keen sense of smell is fully mature at birth

- babies respond negatively to unpleasant odors and positively to pleasant odors

* the control or determination of more than one characteristic or function by a single gene

- most genes affect only one characteristic or function

- e.g. Marfan's Syndrome, which causes a weakened aorta, deformed bone structure, and poor vision

* genetic traits that are controlled by pairs of genes from each parent

- e.g. height, skin color, and weight

* describes one of the two patterns of development (the other being the Cephalocaudal Principal)

- describes the center-outward direction of motor development. 

* asserts that growth progresses from near to far, or outward from the central axis of the body toward the extremities (as opposed to from head to foot)

For instance, children gain control of their torso before their extremities (they can sit independently before they can stand).

* determine the sex of a child

* are either X or Y

- XX = girl

- XY = boy

* most significant form of maturation during puberty

* occurs at different ages

* average onset is about 13 years

* alters hormone levels and creates bodily changes within both genders

* makes both sexes physically capable of reproduction

* massive colleciton of neurons within the spine

* looks like a thick cord or section of rope

* surrounded and protected by the hard bone and cartilate of the vertebrae

* two major functions

1. to rapidly transmit neural impulses to the brain

- all sensory messages transmitted from below the neck to the brain do so through the spinal cord

2. to manage the spinal reflexes

- very simple automatic behaviors that occur without the conscious, voluntary actions of the brain

* fully developed in infants

- they respond similarly to adults in basic tastes

* can be divided into four basic categories

- sweet

- salty

- bitter

- sour

* compared to adults, infants have sweet tastes and strongly dislike sour tastes

* substances taken into the system that can have severe and harmful effects on a fetus, such as:

- cigarette smoke

> may result in low birth weight, asthma, or stillbirth

- alcohol

> may harm children mentally and physically through fetal alcohol syndrome

- drugs

> various negative consequences to the infant

> infants who have been exposed to cocaine are more easily agitated and difficult to soothe than other infants

> Thalodomide led to limb deformities

* the Central Nervous System is the developing system most sensitive to teratogens

* popular 1960's drug prescribed to treat insomnia and nausea

* later proved to be a teratogen that led to limb deformities

* characterized by edema (swelling), high blood pressure, and rapid weight gain without increased  food intake

* pregnant women at special risk

* disorder affecting humans, dogs, cats, and certain other mammals

- caused by parasitic microorganisms that affect the nervous system

- especially damaging to an embryo or fetus

When an individual inherits a gene pair that controls a trait or causes a disease. 

(Remember that single gene-pair inheritance follows the dominance-recessiveness principle)

Eg. Sickle cell anemia, cystic fibrosis, phenylketonuria (PKU), Huntington's disease, and Tay-Sachs disease. All of these are recessive traits, except for Huntington's disease which is carried on a dominant gene.

When a trait or disease like color blindness or hemophilia is carried by a gene on the sex chromosomes. 

Ex.  Color blindness is carried on a recessive gene on the X chromosome and is therefore called a sex-linked recessive trait. A male who inherits this recessive gene will be color blind because it is impossible for him to also have a dominant gene on a second X chromosome to repress the recessive trait. Females who are color blind have a recessive-recessive gene pair. Hemophilia is also carried the same way as color blindness.

Occurs if a child has inherited too few, too many, or abnormal chromosomes. 

Ex. Down's syndrome (trisomy 21) is caused by having three rather than two chromosomes at the 21st chromosome position. 

Turner syndrome occurs when a female is born with only one X chromosome (X0)

Klinefelter's syndrome occurs when a male is born with an extra X chromosome (XXY).

skills that involve small, coordinated movements of the hands, fingers, or toes. 

Infants show a fairly well-developed fine motor skill of manipulating objects with their fingers by about 9-12 months of age.