1I Foundations 9 - Cellular Adaptations Flashcards
What is the underlying dysfunction in Chediak-Higashi syndrome?
Immunodeficiency syndrome where lysosomes of the phagocytes are ineffective
How does having a high cholesterol content in the plasma membrane affect the function of the plasma membrane?
- Decreased fluidity
- Increased melting temperature
A patient presents with an aganglionic colon and other neural crest derivative deficiencies. What other findings would you expect to see?
- PNS abnormalities
- Autonomic dysfunction
- Conductive hearing loss
- Anterior chamber eye problems
- Dental abnormalities
- Albinism
- Heart defects (Truncus arteriosus, Transposition of the great vessels)
What happens cellularly in hypertrophy
Cells become larger by laying down more myofibrils from increased protein production
Uterine muscle during pregnancy is an example of what kind of hypertrophy?
Hormone-induced
What is the most common cause of myocardial hypertrophy?
Chronic hypertension
What is the mechanism of myocardial hypertrophy caused by chronic hypertension?
Increased afterload –> cellular adaptation is hypertrophy –> Stiff left ventricle –> It can’t relax so can’t fill as easily.
What does left ventricular hypertrophy lead to?
Diastolic heart failure
Increase in the size of breasts because of estrogen production is an example of?
Hyperplasia (caused by hormonal changes)
What is metaplasia?
One cell type is replaced by another cell type in response to an ongoing stressor
What is the metaplastic change and other changes that happens in the trachea and bronchi of smokers?
- Ciliated columnar cells –> Squamous cells
- Less mucus production –> respiratory infections
- Transformation to cancer
What is the metaplastic change that happens in Barrett esophagus?
Squamous –> Columnar (Sometimes calles intestinal because columnar is therer)
What causes Barrett esophagus?
Chronic GERD
What’s a precursor to esophageal adenocarcinoma (the most common type of esophageal cancer in the USA)
Barrett esophagus
Define atrophy!
- Reduced size of individual cells
- Reduced number of cells
Causes of atrophy?
- Decreased hormone signals (uterus/vagina)
- Decreased innervation (motor neuron damage)
- Decreased O2 supply and nutrients
- Increased hydrostatic pressure (nephrolithiasis)
- Occlusion of secretory ducts (Cystic fibrosis)
What happens on a cellular level in atrophy?
- Fewer cell organelles
- Decreased metabolic activity –> Decreasedprotein synthesis
- Protein degradation by the Ubiquitin-proteasome pathway
- Autophagy and free radical oxidation
Free radical oxidation of lipids cause some yellow-brown particles to be produced. What are they called?
Lipofuscin
What are telomeres?
Long, non-coding DNA sequences on ends of chromosomes
What happens to telomeres during cell division?
They shorten with each round of cell division
Shorter the telomeres ..
older the cell
What is the function of telomerase?
Elongates telomeres
Where can you find telomerase?
Germ cells and stem cells
Where can you not find telomerase?
Mature somatic cells
How is a method cancer cells can stay alive forever by?
Expressing telomerase
How can you make cells live longer?
Caloric restriction
Does the myometrial growth in pregnancy occur primarily as a result of hyperplasia or hypertrophy?
Hypertrophy
