Critical & Sensitive Periods; Prenatal Development and Birth

Question 1

A ___________________ is a specific, predetermined period of time during biological maturation when an organism is particularly sensitive to certain stimuli that can have either a positive or negative impact on development.

Answer 1

Critical period.

Question 2

_____________________ are longer in duration and more flexible than critical periods, and they are not tied as closely to chronological age and maturational stage.

Answer 2

Sensitive periods.

Question 3

Prenatal development is divided into ___ stages.

Answer 3

3.

Question 4

The first two weeks of prenatal development make up the ________________ stage. During this stage, the fertilized ovum is called a zygote.

Answer 4

Germinal.

Question 5

The _______________ stage of prenatal development encompasses the beginning of the 3rd week through the 8th week.

Answer 5

Embryonic.

Question 6

The __________________ stage of prenatal development begins at the onset of the 9th week and continues until birth.

Answer 6

Fetal.

Question 7

22 pairs of chromosomes are referred to as _________________, while the 23rd pair contains _________ chromosomes.

Answer 7

• Autosomes
• Sex

Question 8

_________________________ is an autosomal dominant gene disorder characterized by a combination of psychiatric, cognitive, and motor symptoms.

Answer 8

Huntington’s Disease.

Question 9

Examples of ____________________ include cystic fibrosis, sickle cell disease, Tay-Sachs disease, and phenylketonuria (PKU).

Answer 9

Recessive Gene Disorders.

Question 10

Disorders due to a variation in chromosome number (________________) include Down Syndrome, Klinefelter Syndrome, and Turner Syndrome.

Answer 10

Aneuploidy.

Question 11

__________________ is an autosomal disorder caused by the presence of an extra chromosome 21; it is characterized by mental retardation, retarded physical growth and motor development, distincitive physical features, and increased susceptibility to Alzheimer’s dementia, leukemia, and heart defects.

Answer 11

Down Syndrome.

Question 12

__________________ occurs in males and is due to the presence of two or more X chromosomes along with a single Y chromosome; a male with this disorder has a small penis and testes, develops breasts during puberty, has limited interest in sexual activity, is often sterile, and may have learning disabilities.

Answer 12

Klinefelter Syndrome.

Question 13

___________________ occurs in females and is caused by the presence of a single X chromosome; females with this disorder are short in stature, have characteristic physical features (e.g., drooping eyelids, webbed neck), have retarded or absent development of the secondary sex characteristics, and may exhibit certain cognitive defects.

Answer 13

Turner Syndrome.

Question 14

A ___________________ occurs when part of a chromosome is missing.

Answer 14

Deletion.

Question 15

___________________ is caused by a chromosomal deletion. Children with this disorder have some degree of mental retardation, are obese, and may exhibit obsessive-compulsive behaviors.

Answer 15

Prader-Willi Syndrome.

Question 16

A _________________ is the transfer of a chromosome segment to another chromosome. A minority of Down’s Syndrome cases involve the attachment of chromosome 21 to another chromosome.

Answer 16

Translocation.

Question 17

An ________________ occurs when a chromosome breaks in two places and the segment formed by the breaks inverts and reattaches to the chromosome; in humans they do not usually affect phenotype.

Answer 17

Inversion.

Question 18

Exposure to teratogens during the ________________ is most likely to cause major structural abnormalities.

Answer 18

Embryonic Stage.

Question 19

Characteristic symptoms of _________________ include facial abnormalities, retarded physical growth, heart, kidney, and liver defects, visual and hearing impairments, mental retardation, learning disabilities, and behavioral problems (e.g., hyperactivity, impulsivity, social withdrawal).

Answer 19

Fetal Alcohol Syndrome (FAS).

Question 20

____________________ is more common than FAS; children with this disorder are less likely to have facial abnormalities and mental retardation but exhibit many other symptoms of FAS, though at a milder level.

Answer 20

Fetal Alcohol Effects (FAE).

Question 21

Regions of the brain most likely to be affected by FAS and FAE include the:

• Corpus callosum
• H_____________
• Hypothalamus
• Cerebellum
• B________________
• Frontal lobes

Answer 21

• Hippocampus
• Basal ganglia

Question 22

___________________ use by pregnant women increases the risk of spontaneous abortion and stillbirth; infants born are at high risk for SIDS, seizures, low birthweight, and reduced head circumference. They often exhibit tremors, an exaggerated startle response, a high-pitched cry, sleep and feeding difficulties, and developmental delays; they tend to be irritable and difficult to comfort.

Answer 22

Cocaine.

Question 23

____________________ is associated with placental abnormalities that can cause fetal death and stillbirth; infants are at higher risk for low birthweight, SIDS, and respiratory diseases, and may have emotional and social disturbances and cognitive deficits.

Answer 23

Cigarette smoking.

Question 24

Exposure to ____________ during prenatal development is associated with a low birthweight and mental retardation.

Answer 24

Lead.

Question 25

If a pregnant woman is infected with _______________, especially during the first trimester, the infant is at high risk for heart defects, blindness, deafness, and mental retardation.

Answer 25

Rubella.

Question 26

_______________________is passed through an infected woman to her fetus through the placenta; approximately 1% of all newborns are infected; 10% of these have symptoms at birth (low birthweight, petechial rash, microencephaly, enlarged liver/spleen, retinal inflammation, calcium depositis in the brain) while 20-30% die perinatally. 80-90% of symptomatic newborns and 10-15% of infected but aysmptomatic newborns develop neurological symptoms in the first few months to years of life (e.g., mental retardation, hearing and visual impairments).

Answer 26

Cytomegalovirus (CMV).

Question 27

The risk that an infected mother will transmit HIV to her infant is estimated to be between ___ and ___%. Perinatal administration of AZT during preganacy and delivery reduces this risk.

Answer 27

35 and 60%.

Question 28

Babies with ________ are frequently small for gestational age, and most show multiple signs of the virus during the first year of life (e.g., greater-than-normal susceptibility to infections, enlarged liver and spleen, swollen lymph nodes, oral candidiasis). In early childhood, they have immunologic abnormalities and delays in phsyical and cognitive development. With antiviral treatment, 1/3 survive to age 8 or beyond.

Answer 28

HIV.

Question 29

____________________ during prenatal development is associated with miscarriage, stillbirth, and low birth weight, and may result in suppression of the immune system, mental retardation, and other serious problems.

Answer 29

Malnutrition.

Question 30

Severe malnutrition (esp. ______________ deficiency) during the 3rd trimester is particularly detrimental for the developing brain and can lead to a reduced number of neurons, reduced myelinization, and neurotransmitter abnormalities.

Answer 30

Protein.

Question 31

A lack of ____________ during prenatal development can result in spina bifida or other neural tube defect.

Answer 31

Folic acid.

Question 32

Prolonged _______________ during pregnancy places a woman at higher risk for miscarriage, painful labor, premature delivery, and her baby is more likely to have a low birthweight, be hyperactive and irritable, and to exhibit irregular feeding, sleeping, and bowel habits. This can be mitigated by the presence of adequate support prior to and during pregnancy.

Answer 32

Emotional stress.

Question 33

An infant born less than ___ weeks after conception is considered premature or pre-term.

Answer 33

37.

Question 34

When a newborn’s weight is below the ___th percentile for his/her gestational age, the infant is small-for-gestational age (SGA).

Answer 34

10th.

Question 35

SGA infants are at high risk for:

• ___________ during birth
• Respiratory disease
• Hypoglycemia
• ____________ disabilities
• ADHD

Answer 35

• Asphyxia
• Learning

Question 36

During birth, consequences of _______________ include delayed motor and cognitive development, mental retardation, and, in severe cases, cerebral palsy.

Answer 36

Prolonged anoxia (oxygen shortage).

Question 37

When an infant is exposed to _______________ during the birth process, there is a high risk for death, brain damage, or blindness. Thus, women with this disease typically deliver through Cesarean Section.

Answer 37

Herpes Simplex 2.