Chapters 4-6

Question 1

Abnormalities of a body structure, function, or metabolism that are present at birth

• affect more than 185,000 infants discharged from the hospital in the U.S. each year and are the leading cause of deaths in infants
• may be caused by genetic factors (single-gene or multifactorial inheritance or chromosomal aberrations) or environmental factors that are active during embryonic or fetal development
• may not make an appearance until later in life

Answer 1

Congenital Defect (Birth Defects)

Question 2

Caused by defective or mutant allele at a single gene locus and follow Mendelian patterns of inheritance

• characterized by their patterns of transmission, usually obtained through a family genetic history
• virtually all lead to formation of an abnormal protein pr the decreased production of a gene product

Answer 2

Single-Gene Disorders

Question 3

A single mutant allele from an affected parent is transmitted to an offspring regardless of sex

• affected parent has 50% chance of transmitting the disorder to each offspring
• may also manifest as a new mutation
• Marfan syndrome
• Neurofibromatosis

Answer 3

Autosomal Dominant Disorders

Question 4

Manifested only when both members of the gene pair are affected (homozygous)

• both parents are unaffected but are carriers of the defective gene
• affect both sexes
• Consanguineous mating (inbreeding) increases the chance that 2 people who mate will be carriers
• age of onset=early in life
• PKU
• Tay-Sachs Disease

Answer 4

Autosomal Recessive Disorders

Question 5

• form a major category of genetic disease, accounting for a large portion or early miscarriages, congenital malformations, and intellectual disability
• cytogenetics: study of chromosomal disorders
• structural chromosomal abnormalities
• numeric disorders involving autosomes
  
  • Down syndrome (trisomy 21, risk increases with maternal age)
• numeric disorders involving sex chromosomes
  
  • Turner syndrome (absence of all or part of the X chromosome, females)
  • Klinefelter syndrome (presence of one or more extra X chromosomes, males)

Answer 5

Chromosomal disorders

Question 6

• radiation
• chemicals and drugs
• infectious agents

Answer 6

Teratogenic agents

Question 7

• cancer is a disorder of altered cell differentiation and growth
• tends to be uncoordinated and relatively autonomous in that it lacks normal regulatory controls over cell division and growth

Answer 7

Neoplasia

Question 8

-the mechanism by which cells become increasingly more specialized which each mitotic division

Answer 8

Differentiation

Question 9

-form of programmed cell death that eliminates senescent and some types of injured cells (DNA damage or hydrogen peroxide-induced injury)

Answer 9

Apoptosis

Question 10

• A swelling that can be caused by a number of conditions (inflammation and trauma)
• used to define a mass of cells that arises because of overgrowth
• tumor and neoplasm are interchangeable
• neoplasms are usually classified as benign or malignant
  
  • benign: contain well differentiated cells that are clustered together in a single mass (usually do not cause death unless location interferes with vital functions)
  • malignant: less well differentiated and have the ability to break loose, enter the circulatory or lymphatic system, and form secondary malignant tumors at other sites

Answer 10

Tumor

Question 11

• benign tumors are usually named by adding the suffix -oma to the parenchymal tissue type from which the growth originated
  
  • glandular epithelial tissue=adenoma
  • Bone tissue=osteoma
• malignant tumors of epithelial tissue origin are designated by the word carcinoma
  
  • glandular epithelial tissue=adenocarcinoma
  • mesenchymal origin=sarcoma

Answer 11

Tumor naming

Question 12

• invade and destroy nearby tissue and spread to other parts of the body, tend to grow rapidly and spread widely and have the potential to cause death
• may compress blood vessels and outgrow their blood supply, causing ischemia and tissue injury
• some secrete hormones or cytokines, release enzymes and toxins, or induce and inflammatory response that injures normal tissue as well as the tumor
• 2 categories
  1) solid tumors:initially are confined to a specific tissue or organs; as the growth of the primary solid tumor progresses, cells detach from the original tumor mass, invade surrounding tissue, and enter the blood and lymph systems to spread to distant sites, called METASTASIS
  2) hematologic cancers:involve cells normally found in the blood and lymph, thereby making them disseminated diseases from the beginning

Answer 12

Malignant Neoplasims

Question 13

• characterized by 2 main features
  1) abnormal and rapid proliferation
  2) loss of differentiation-means that they do not exhibit normal features and properties of differentiated cells and are more similar to embryonic cells (asplasia)

Answer 13

Cancer cell characteristics

Question 14

• rate of tissue growth in normal and cancerous tissues depends on 3 factors:
  1) the number of cells that are actively dividing or moving through the cell cycle
  2) the duration of the cell cycle
  3) the number of cells that are being lost relative to the number of new cells being produced

Answer 14

Tumor growth

Question 15

• the causes of cancer are very diverse and complex:
  1) genetic and molecular mechanisms that are involved and that characterize the transformation of normal cells to cancer cells (cancer associated genes)
  2) the external and more contextual factors such as age, heredity, and environmental agents that contribute to the development and progression of cancer

Answer 15

Etiology of Caner

Question 16

• generalized manifestations
  
  • fatigue
  • anorexia
  • cachexia
  • anemia
  • decreased resistance to infections
  • symptoms unrelated to the tumor site
  • pain (late stages)
  • disrupts tissue integrity

Answer 16

Clinical manifestations of cancer

Question 17

• grading:according to histologic or cellular characteristics of the tumor
• staging:according to the clinical spread of the disease
• both are used to determine the course of the disease and aid in selecting an appropriate treatment or management plan
• grading involves microscopic examination of cancer cells to determine their level of differentiation and the number of mitoses
• cancers are classified as grades I, II, III, IV
• staging uses methods to determine the extent and spread of the disease
• surgery may be used to determine tumor size and lymph node involvement
• TNM system: classifies the disease into stages using 3 tumor components
  1) T-size and local spread of the primary tumor
  2) N-refers to the involvement of the regional lymph nodes
  3) M-describes the extent of the metastatic involvement

Answer 17

Staging and grading of tumors