Anemia and Muscle Cell Differences

Flashcards on types of anemia and differences between cardiac and skeletal muscle cells.

What is the cause of Aplastic anemia?

Toxic chemicals, radiation

What defect is associated with Aplastic anemia?

Damaged bone marrow

What is the cause of Hemolytic anemia?

Toxic chemicals

What defect is associated with Hemolytic anemia?

Red blood cells destroyed

What is the cause of Iron deficiency anemia?

Dietary lack of iron

What defect is associated with Iron deficiency anemia?

Hemoglobin deficient

What is the cause of Pernicious anemia?

Inability to absorb vitamin B12

What defect is associated with Pernicious anemia?

Excess of immature cells

What is the cause of Sickle cell disease?

Defective gene

What defect is associated with Sickle cell disease?

Red blood cells abnormally shaped

What is the cause of Thalassemia?

Defective gene

What defect is associated with Thalassemia?

Hemoglobin deficient; red blood cells short-lived

What is the typical size of Cardiac Muscle Cells?

10-20 μm x 50-100 μm

How many nuclei do Cardiac Muscle Cells typically have?

Typically 1 (rarely 2-5)

What contractile proteins are found in Cardiac Muscle Cells?

Sarcomeres along myofibrils

What is the structure of internal membranes in Cardiac Muscle Cells?

Short T tubules; no triads formed with sarcoplasmic reticulum

How abundant are mitochondria in Cardiac Muscle Cells?

Abundant (25% of cell volume)

What inclusions are found in Cardiac Muscle Cells?

Myoglobin, lipids, glycogen

How extensive is the blood supply to Cardiac Muscle Cells?

Very extensive

What is the metabolism of Cardiac Muscle Cells at rest?

Aerobic, primarily using lipids and carbohydrates

What type of contractions do Cardiac Muscle Cells exhibit?

Twitches with brief relaxation periods; long refractory period prevents tetanic contractions

What stimulates contraction in Cardiac Muscle Cells?

Autorhythmicity of pacemaker cells generates action potentials

What triggers contraction in Cardiac Muscle Cells?

Calcium entry from the ECF and calcium release from the sarcoplasmic reticulum

What are the intercellular connections in Cardiac Muscle Cells?

Branching network with plasma membranes locked together at intercalated discs; connective tissue fibers tie adjacent layers together

What is the size of Skeletal Muscle Fibers?

100 μm X up to 40 cm

How many nuclei do Skeletal Muscle Fibers have?

Multiple (hundreds)

What contractile proteins are found in Skeletal Muscle Fibers?

Sarcomeres along myofibrils

What is the structure of internal membranes in Skeletal Muscle Fibers?

Long T tubules form triads with cisternae of the sarcoplasmic reticulum

How abundant are mitochondria in Skeletal Muscle Fibers?

Much less abundant

What inclusions are found in Skeletal Muscle Fibers?

Little myoglobin, few lipids, but extensive glycogen reserves

How extensive is the blood supply to Skeletal Muscle Fibers?

More extensive than in most connective tissues, but sparse compared with supply to cardiac muscle cells

What is the resting metabolism of Skeletal Muscle Fibers?

Aerobic, primarily lipid-based

What is the active metabolism of Skeletal Muscle Fibers?

Anaerobic, through breakdown of glycogen reserves

What type of contractions do Skeletal Muscle Fibers exhibit?

Usually sustained contractions

What stimulates contraction in Skeletal Muscle Fibers?

Activity of somatic motor neuron generates action potentials in sarcolemma

What triggers contraction in Skeletal Muscle Fibers?

Calcium release from the sarcoplasmic reticulum

What are the intercellular connections in Skeletal Muscle Fibers?

Adjacent fibers tied together by connective tissue fibers