development & genetic disorders

Question 1

What is caused by exp to neg environ stimuli either before or during prego.
what are some causes?

Answer 1

developmental disorder

radiation, drugs, cocaine abuse, maternal infection

Question 2

____ are defects in development during embryonic stage (0-8 wks) that aren’t due to chromo or genetic abnormalities. causes can be unknown.

Answer 2

congenital anomaly

Question 3

what causes are there for congenital anomalies?

Answer 3

time issues - exposure to harmful influence in first 2 weeks of embryo development
teratogens - chemical (physical and bio) agents
TORCH - toxoplasmosis, Other (mumps, hep B, varicella, gonorrhea, syphilis) Rubella, Cytomegalovirus, Herpes
Negative stimuli - radiation (sperm and ova), alcohol (FAS), smoking (low birth rate) and cocaine abuse (premature labor, increase risk of infection, sudden infant death syndrome).

Question 4

what are genetics?

Answer 4

the study of the behavior and functions of the genes

Question 5

what project has helped to identify thousands of disorders?

Answer 5

Human Genome Project

Question 6

What is a basic unit of hereditary located on a very specific area on the chromosome? How many copies do we have?

Answer 6

gene

2

Question 7

_____ is a very complex structure that houses thousands of genes. Genetic info is encoded on the DNA.

Answer 7

Chromosome

Question 8

____ contains all genetic info in the nucleus of each cell and transmits the info to new cells w/ division. It dictates how protein in each chromosome is to be utilized.

Answer 8

DNA

Question 9

normal human cells have ___ chromosomes arranged in ___ pairs and ___ are from mom’s ovum and ___ are from dad’s

Answer 9

46

23 (rest of answers)

Question 10

What is the group name for 22 pairs of chromosomes?

Answer 10

automsomes

Question 11

what is the name for the group of one chromosomes?

Answer 11

sex chromosome

Question 12

XX

XY

Answer 12

female X from each parent

male big X from mom and sm Y from dad

Question 13

___ is a way to map all of the chromosomes in an indiv cell

Answer 13

karyotype

Question 14

_____ are inherited chromosomes

what kinds are there?

Answer 14

genetic traits
homozygous – 2 genes are the same
heterozyogous – 2 genes are different

Question 15

___ is an alteration in DNA inherited or acquired throughout our lifetime as we are exposed to various chemicals as our cells age

Answer 15

genetic mutation

Question 16

____ is classified as autosomal dominant, autosomal recessive, sex (X) linked

Answer 16

single gene abnormalities/disorder

Question 17

What is an autosomal dominant gene

Answer 17

if present will cause the disease to be active even when only one copy is present. 50% single-gene disorder are said to autosomal dominant. ppl w/ the disorder have a 50% chance of producing a child w/ the disorder.

• male and female equally affected
• defective gene can be transmitted to successive generations
• unaffected members do not transmit the gene to their offspring

Question 18

what disease is progressive of the nervous system characterized by involuntary twitching movements of arms, legs, face, body. Patients also develop concentration, memory and emotional problems that eventually prevent them for day to day living. symptoms don’t begin until middle age. survive 15-20yrs after symptoms begin. no cure. ~30k ppl in US affected and 150k are “at risk”

Answer 18

Huntington’s Disease

Question 19

disorder affecting heart, aorta, skeleton, eyes, and skin. lanky long tall skinny syndrome that Abraham Lincoln was said to have.

Answer 19

Marfan Syndrom

Question 20

development of multiple benign tumors

Answer 20

neurofibromatosis

Question 21

What autosomal issue has clinical symptoms only when both chromosomes have the defective gene. homozygous defective genes. transmitted to male and female equally

Answer 21

autosomal recessive

Question 22

when both parents = heterozygous for trait and no clinical symptoms what % of offspring will be affected and how? Why does this happen?

Answer 22

1/2 - carriers
1/4 - will show symptoms - must inherit 2 copies of defective gene (one from each parent carrier).
generally product of consanguineous marriages (descendent from common blood ancestor)

Question 23

list 4 eg of autosomal recessive diseases

Answer 23

1) cystic fibrosis - incurable. exocrine gland. pancreas/respiratory and sweat glands affected. sticky mucous develops cuasing obstruction, infections poor digestion and death. 1:3900 babies most Caucasian
2) Phenylketonuria (PKU) - 1:50 ppl in US carry 1 defective PKU gene. failure to oxidize amino acid, buildup causes mental retardation and brain damage. pale appearance
3) sickle cell anemia - affects bone marrow, lymph glands, spleen, liver and thymus. infections, damage to major organs, back, chest, abdomen pain. ~72,000 ppl in US primarily African Americans. others: Mediterranean, Middle East, India
4) tay-Sachs Disease - rare, fatal CNS, infants and young. lack metabolism enzyme. causes progressive impairment and early death. mental retardation, loss of muscle, constipation. Eastern European jewish descent.

Question 24

these diseases will always be present in males
females may be homozygous or heterozygous (may or may not display trait)
fathers cannot pass this gene on to sons but pass it on to ALL daughter
e.g. muscular dystrophy (most types x-linked) Becker or Duchenne almost all boys; hemophilia A - blood clotting disorder; color blindness

Answer 24

X-linked

Question 25

Name 2 numerical chromosomal abnormalities

Answer 25

Down's syndrome (trisomy 21) - high risk preg after 35 ~1:1000
Klinefelter Syndrome (47, XXY) - hypogonadism and infertile. 1:500 men

Question 26

what type of disease is caused by several genes as well sa teh influence of environment (diet, lifestyle)
give 2 examples

Answer 26

multifactoral disorders
anencephaly & cleft lip/cleft palate (women who binged in first tri were twice as likely to have baby w/ this. triples if binge 3+ times in first tri)