M2P Second Exam2 Flashcards
Functions of Connective Tissue
provides structural support; underlies epithelium (ligaments, tendons, aponeuroses, bone, cartilage); establishes immunological barrier; energy storage; water storage
Categories of Cells in ECM
fixed cells, hematogenous cells
Fixed cells are
mesenchymal, fibrocytes, adipose cells
Hematogenous cells are
macrophages, mast cells, blood cells, lymphocytes, polymorphonuclear cells
Extracellular matrix is made up of
fibers (collagen, elastic, reticular); ground substance (GAGs, proteoglycans, adhesive glycoproteins); tissue fluid
Three fiber types
Collagen; elastin; reticular (collagen III)
What composes ground substance?
Glycosaminoglycans (GAGs/Polysaccharides); proteoglycans; adhesive glycoproteins
What is GAGs composition/function?
long chain of unbranched polysaccharides consisting of repeating disaccharides – acid sugar/amino sugar – Consists of an overall negative charge (basophilic); attract and bind cations, high H2O creates turgor i.e. resistance to compression
Describe components/function of: Fibronectin
dimer of identical subunits bound end-to-end; links cells and ground substance; involved in embryological cell migration binds: integrins, collagen, heparin sulfate PG
Describe components/function of: Laminin
trimer of intertwined polypeptides, forms cross-shaped protein; links: cells, fibers & ground substance; found almost exclusively in basal lamina. Has specific binding domains binds: GAGs, proteoglycans, & other adhesive glycoproteins (integrins, heparin sulfate PG, collagen IV, entactin)
Describe components/function of: Entactin
binds laminin and collagen IV
Describe components/function of: Tenascin
large hexamer, binds fibronectin & transmembrane PGs
Describe components/function of: Chondronectin
like fibronectin, binds collagen II, integrins & GAGs
Describe components/function of: Osteonectin
like fibronectin, binds collagen I, integrins & PGs, binds calcium (hydroxyapatite) to collagen I in bone
Describe components/function of: Integrins
heterodimeric integral membrane proteins, divalent cations (Ca, Mg, Mn) required to activate binding Binds: GAGs and proteoglycans, adhesive glycoproteins, other integrins; intracellular domain binds: cytoskeletal elements COOH terminal binds intermediary proteins Vinculin & Talin bind to actin
What pathology is associated with: Collagen I
Osteogenesis Imperfecta (and EDS with type III)
What pathology is associated with: Collagen II
Collagenopathy
What pathology is associated with: Collagen III
EDS – Ehlers-Danlos Syndrome
What pathology is associated with: Collagen IV
Alport Syndrome
What pathology is associated with: Collagen VII
Epidermolysis Bullosa
What pathology is associated with: Collagen XVII
Bullous Pemphigoid
What Collagen fiber is affected in Osteogenesis Imperfecta?
Collagen I
What collagen fiber is affected in Collagenopathy
Collagen II
What collagen fiber is affected in Ehlers-Danlos Syndrome?
Collagen III
What collagen fiber is affected in Alport Syndrome
Collagen IV
What collagen fiber is affected in Epidermolysis Bullosa
Collagen VII
What collagen fiber is affected in Bullous Pemphigoid
Collagen XVII
Which collagen fiber has a globular shape?
Collagen type IV
What are the periods of human development?
Early development; Embryonic Period; Fetal Period
When does early development occur?
Fertilization through week 2
When does Embryonic period occur?
Weeks 3-8
When does Fetal period occur?
Weeks 9 through birth (approx 38)
Define Teratogenesis/Teratogen
mechanism by which birth defect form – Teratogen is a substance that causes birth defects
Which period of development has the highest mortality rate for embryos?
Early development; fertilization to week 2 (approx 25-50 percent loss)
Which period has the most significatn risk for development of embryonic birth defects?
weeks 3-8; Embryonic period
Surge of what hormone causes Ovulation?
Luetinizing Hormone (LH)
What two hormones build up during the ovarian cycle?
Follicle stimulating hormone (FSH) and Leutinizing hormone (LH)
What hormone will be released by? What cells are involved?
human chorionic gonadotrophin released by the implanted conceptus: syncitiotrophoblasts
What hormone maintains the uterine wall? How is this caused?
Feed back loop; hCG stimulates the corpus leutum to release Progesterone
What is involved in capacitation?
“Take off your coat and stay awhile” Uterine enzymes aid removal in the glycoproteins and seminal proteins on the spermatozoa head
What are the phases of fertilization?
Phase 1: Penetration of Corona Radiata; Phase 2: Penetration of Zona Pellucida; Phase 3: Fusion of the Sperm and Oocyte membranes
What does Fusion of the oocyte and sperm membranes cause?
Acrosomal events: including hardening of the zona pellucida to prevent poly-spermia
When does the Oocyte finish meiosis II?
Between penetration of zona pellucida and fusion of the spermatzoa/oocyte membranes
At what stage does the zygote lose its zona pellucida? What does it become?
Morula; Morula becomes a Blastocyst
What cells make up a Blastocyst? What days of development does this occur?
Embyoblasts and Trophoblasts; Day 4
What is the process of implantation called?
Embryonic Rolling
What cell layers make up an embryoblast? What days does this occur?
Epiblast, hypoblast, cytotrophoblast, synctiotrophoblast, Amnioblasts - days 8-9
What is the orientation of the epiblast cells? What does it give rise to?
Dorsal; amnioblast (placenta)
What is the orientation of the hypoblast cells?
Ventral, yolk sac, embryo
What does the Embryobalst comprised of? What days does this occur?
Trophoblastic Lacunae, endoderm cells, mesoderm cells, ectoderm cells, exocelomic cavity, exocoelomic membrane, extraembryonic somatic mesoderm, extraembryonic splanchnic mesoderm, extraembryonic cavity; Week 2
What occurs in preeclampsia?
The syncytiotrophoblast cells are unable to invade into the maternal sinusoids and cause the bursting of the spiral arteries to form the placenta
What are the 4 fetal membranes?
Amnion, yolk sac, allantois, placenta
What is the one ectopic pregnancy condition that can be a viable fetus?
Placenta Previa; implantation over the cervix (high risk pregnancy) usually requires bed rest of the mother
What condition(s) are classified by “cluster of grapes”?
Hydatidiform Mole/Partial Moles - consisting of water filled cysts.
How are hydatidiform moles created?
- Resulting from fertilization of an empty Oocyte - male pronucleus replicates and there is significant trophoblastic cells without embriocytes 2. Partial Moles - poly spermia from poor corital reaction
What is persistent trophoblastic disease?
The hydatidiform mole is not completely removed and remains invasive proliferative tissue (creates choriocarcinomas)
When does gastrulation occur?
Week 3 of development
When does the bilaminar disc become a trilaminar disc?
Gastrulation
How are the three layers formed?
During gastrulation, there is a signal from the primitive node for cells to migrate through the primitive streak and form: Ectoderm, Mesoderm, & Endoderm
What is the most common teratoma in infancy?
Sacrococcygeal teratoma
What forms the musculoskeletal system?
Mesoderm
What forms the GI system?
Endoderm
What forms the neural and skin layers?
Ectoderm
What is the most important factor for viability of the fetus at birth?
The presence of surfactant in the lungs
When does surfactant start to be secreted into the lungs?
Weeks 21-28 of development
What is the purpose of surfactant in the lungs?
Decrease the surface tension so they lungs can breath air
What are the four basic tissue types?
Connective tissues, neuronal tissue, epithelia, muscle
What are the changes that occur in adaptive processes?
Hypertrophy, hypotrophy, metaplasia, hyperplasia
What are the characteristics of hypertrophy?
Growth of the cell
What is an example of hypertrophy?
Pregnant uterus, left ventricular hypertrophy
What are the charactertistics of atrophy?
Cell compensates by getting smaller
What is an example of atrophy?
Muscles wasting away with malnutrition/decreased stimulation
What are the characteristics of metaplasia?
Cell changes its function
What is an example of metaplasia?
Pulmonary alveolar tissue from cigarette smoke
What are the characteristics of hyperplasia?
Cell will proliferate (grow in number)
What is an example of hyperplasia?
Liver regeneration, endometrial, lactation
Which period of development has the highest mortality rate for embryos?
Early development; fertilization to week 2 (approx 25-50 percent loss)
Which period has the most significatn risk for development of embryonic birth defects?
weeks 3-8; Embryonic period
Surge of what hormone causes Ovulation?
Luetinizing Hormone (LH)
What two hormones build up during the ovarian cycle?
Follicle stimulating hormone (FSH) and Leutinizing hormone (LH)
What hormone will be released by? What cells are involved?
human chorionic gonadotrophin released by the implanted conceptus: syncitiotrophoblasts
What hormone maintains the uterine wall? How is this caused?
Feed back loop; hCG stimulates the corpus leutum to release Progesterone
What is involved in capacitation?
“Take off your coat and stay awhile” Uterine enzymes aid removal in the glycoproteins and seminal proteins on the spermatozoa head
What are the phases of fertilization?
Phase 1: Penetration of Corona Radiata; Phase 2: Penetration of Zona Pellucida; Phase 3: Fusion of the Sperm and Oocyte membranes
What does Fusion of the oocyte and sperm membranes cause?
Acrosomal events: including hardening of the zona pellucida to prevent poly-spermia
When does the Oocyte finish meiosis II?
Between penetration of zona pellucida and fusion of the spermatzoa/oocyte membranes
At what stage does the zygote lose its zona pellucida? What does it become?
Morula; Morula becomes a Blastocyst
What cells make up a Blastocyst? What days of development does this occur?
Embyoblasts and Trophoblasts; Day 4
What is the process of implantation called?
Embryonic Rolling
What cell layers make up an embryoblast? What days does this occur?
Epiblast, hypoblast, cytotrophoblast, synctiotrophoblast, Amnioblasts - days 8-9
What is the orientation of the epiblast cells? What does it give rise to?
Dorsal; amnioblast (placenta)
What is the orientation of the hypoblast cells?
Ventral, yolk sac, embryo
What does the Embryobalst comprised of? What days does this occur?
Trophoblastic Lacunae, endoderm cells, mesoderm cells, ectoderm cells, exocelomic cavity, exocoelomic membrane, extraembryonic somatic mesoderm, extraembryonic splanchnic mesoderm, extraembryonic cavity; Week 2
What occurs in preeclampsia?
The syncytiotrophoblast cells are unable to invade into the maternal sinusoids and cause the bursting of the spiral arteries to form the placenta
What are the 4 fetal membranes?
Amnion, yolk sac, allantois, placenta
What is the one ectopic pregnancy condition that can be a viable fetus?
Placenta Previa; implantation over the cervix (high risk pregnancy) usually requires bed rest of the mother
What condition(s) are classified by “cluster of grapes”?
Hydatidiform Mole/Partial Moles - consisting of water filled cysts.
How are hydatidiform moles created?
- Resulting from fertilization of an empty Oocyte - male pronucleus replicates and there is significant trophoblastic cells without embriocytes 2. Partial Moles - poly spermia from poor corital reaction
What is persistent trophoblastic disease?
The hydatidiform mole is not completely removed and remains invasive proliferative tissue (creates choriocarcinomas)
When does gastrulation occur?
Week 3 of development
When does the bilaminar disc become a trilaminar disc?
Gastrulation
How are the three layers formed?
During gastrulation, there is a signal from the primitive node for cells to migrate through the primitive streak and form: Ectoderm, Mesoderm, & Endoderm
What is the most common teratoma in infancy?
Sacrococcygeal teratoma
What forms the musculoskeletal system?
Mesoderm
What forms the GI system?
Endoderm
What forms the neural and skin layers?
Ectoderm
What is the most important factor for viability of the fetus at birth?
The presence of surfactant in the lungs
When does surfactant start to be secreted into the lungs?
Weeks 21-28 of development
What is the purpose of surfactant in the lungs?
Decrease the surface tension so they lungs can breath air
What are the four basic tissue types?
Connective tissues, neuronal tissue, epithelia, muscle
What are the changes that occur in adaptive processes?
Hypertrophy, hypotrophy, metaplasia, hyperplasia
What are the characteristics of hypertrophy?
Growth of the cell
What is an example of hypertrophy?
Pregnant uterus, left ventricular hypertrophy
What are the charactertistics of atrophy?
Cell compensates by getting smaller
What is an example of atrophy?
Muscles wasting away with malnutrition/decreased stimulation
What are the characteristics of metaplasia?
Cell changes its function
What is an example of metaplasia?
Pulmonary alveolar tissue from cigarette smoke
What are the characteristics of hyperplasia?
Cell will proliferate (grow in number)
What is an example of hyperplasia?
Liver regeneration, endometrial, lactation
