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
What’s the fiction of sER in the liver
Metabolism of glycogen and detoxification of noxious metabolic byproducts , drugs and alcohol
What are the faces of the Golgi apparatus
Cis and Trans
What’s the structure of the Golgi apparatus
The Golgi apparatus consists of stacked, saucer-shaped membrane-bound cisternae. The outermost cisternae take the form of a network of tubules known as the cis and trans Golgi networks.l
What do lysosomes contain
Acid hydrolases eg lipase, glucosidase, ACID PHOSPHATASES, nucleases, endoprotease
What do peroxisomes contain
Oxidases and Catalases
Function of lysosomes
involved in the degradation of particulate material ingested by endocytosis.
What do oxidase enzymes do
Oxidase enzyme leads to the production of H2O2 useful for killing ingested microorganisms.
What do catalase enzymes do
Catalase enzyme regulates H2O2 concentration and has a protective effect by oxidizing toxic substances such as phenols and alcohol.
What happens when the phagosomes don’t bind the lysosomes to create a bacteria
Leads to a disease called CHEDIAK HEGASHI SYNDROME
What’s the structure of a mitochondria
Relatively large, elongated organelles with smooth outer membranes and a convoluted inner membrane system.
What’s the site for aerobic respiration
Mitochondria
What’s the site for the oxidation of fatty acid to CO2 and water which releases ATP
Mitochondria
What’s the function of the Golgi apparatus
Site for the maturation of synthesized proteins
Difference in the cell membrane in necrosis and apoptosis
Necrosis : Cell membrane is destroyed
Apoptosis : Cell membrane is intact
What is hereditary stomatocytosis I’m RBC
Marked increase of
intracellular sodium because the cell is unable to
regulate cation homeostasis.
What is cystic fibrosis
Mutation in CFTR gene leading to
production of abnormally folded membrane protein
which is degraded by the cell.
What is Wilson’s disease
Mutation in Wilson disease protein
(ATP7B) gene. Leads to Cu accumulation.
