The Human Cell Flashcards
What is cell differentiation
Modification of cells to perform specific actions
Components of plasma membrane
Phospholipid bilayer
•Cholesterol molecules
•Proteins
•Glycocalyx
Describe the phospholipid molecule in the cell membrane
Amphipatic
-Polar heads derived from glycerol conjugated to a nitrogenous compound e.g choline
-Non polar tail consists of two long chain fatty acids
What’s the ratio of cholesterol to phospholipid in the bilateral
1:1
Function of the cholesterol in the bilayer
Help to stabilize and regulate the fluidity of the phospholipid bilayer
Components of the nucleus
•DNA (making up less than 20% of its mass)
•Protein (nucleoprotein)
•Ribonucleic acid (RNA) –mRNA, tRNA, rRNA
Function of the nucleus
Protein synthesis (along with ribosomes)
How is protein synthesized in the nucleus
•The DNA template is copied to form a complementary messenger RNA (mRNA) copy (transcription)
What is the RER continuous with
The rER is continuous with the outer lipid bilayer of the nuclear membrane
What’s the structure of the endoplasmic reticulum
The endoplasmic reticulum consists of an interconnecting network of membranous tubules, vesicles and flattened sacs ramifying throughout the cytoplasm.
What’s attached to the rER
Proteins destined for export, lysosomal proteins, and integral membrane proteins are synthesised by ribosomes attached to the surface of the rER .
Function of the sER
The principal functions of the sER are lipid biosynthesis and membrane synthesis and repair.
In muscle cells, what’s sER called and what’s it’s function
Sarcoplasmic reticulum
Involved in the storage and release of calcium ions
Where are fatty acids and Triglycerides synthesized
Cytosol
Where are cholesterol and phospholipids synthesized
sER