Cellular Physiology I Flashcards
membranes
provide protection and regulate the movemnt of substances in and out of the cell
organelles
internal structure of a cell resposible for performing specialised metablic tasks
What is the largest organelle in a cell?
Nucleus
Typically 5 µm in diameter and stores most of the cell’s DNA.
What are the two main functions of the nuclear envelope?
double membrane with poses regulating molecular traffic
Regulates molecular traffic in and out of the nucleus
RNA exits while enzymes, proteins, and materials for DNA/RNA synthesis enter.
what is the Nucleolus
largest structure in the nucleus and the site of ribosome production
What is the primary function of mitochondria?
Generate ATP
Known as the ‘powerhouse’ of the cell.
what is the structure of the mitocondria
Double membrane
- inner membrane forms folds (cristae) where ATP synthesis occurs.
- Matrix: Space between cristae containing ribosomes, DNA, and enzymes.
What is the structure of the Golgi apparatus?
Modifies, sorts, and packages proteins (for secretion, membrane insertion or lysosomes)
Also synthesizes carbohydrates and refines proteins.
what is the endoplasmic reticulum (ER)
a structure continuous with the outer membrane of the nuclear envelope
What does the rough endoplasmic reticulum do?
Synthesizes proteins destined for organelles, secretion, or the plasma membrane
Covered in ribosomes.
What is the function of lysosomes?
enzyme-filled vesicles
Digest cellular debris and pathogens
Facilitates autophagy to recycle organelles.
What do peroxisomes do?
Oxidise organic molecules and neutralize toxins
Break down fatty acids for ATP synthesis.
What is the primary role of ribosomes?
Translate mRNA into proteins
Known as ‘protein factories’.
What does the cytoskeleton provide?
Structural support, cell division, and movement
Maintains shape and organizes organelles.
What is the function of centrioles?
Organize microtubules during cell division
Important for chromosome separation.
What is the structure of the plasma membrane?
Hydrophilic heads and hydrophobic tails
Acts as a selective barrier controlling substance entry/exit.
What are the four primary tissue types?
Nervous, Muscular, Epithelial, Connective
Each has distinct functions and structures.
What is the function of nervous tissue?
Control and communication via electrical/chemical signals
Composed of neurons and neuroglia.
What type of tissue is responsible for movement?
Muscular tissue
Includes skeletal, cardiac, and smooth muscle types.
What is the function of epithelial tissue?
Covers surfaces and lines organs
Includes various types such as simple and stratified.
What are tight junctions?
Seals the gap between cells
Prevents substances from passing between cells.
What are desmosomes?
Strong attachments resisting mechanical stress
Do not prevent substances from going between cells.
What do gap junctions allow?
Passage of ions and molecules between cells
Formed by connexons and connect cytoplasms.
What is autocrine communication?
Cell signals itself
Involves short distances (<20µm).
