Chapter 3 Flashcards
Life of the Cell
What is a Prokaryote
single celled orgsnism include bscteria and cyanobacteria
What is a Eukaryote
contains a well-defined nucleus surrounded by nuclear membrane. can be single celled or multicellular
what are the the two main compartments in the cell structure.
the nuclear compartment which contains the nucleus and the cytoplasmic compartment.
What makes up the nuclear component
contains the genetic information and regulates the structure and function of the cell.
What makes up the cytoplasmic compartment
it is the space between the nucleus and the plasma membrane. it contains numerous cellular organelles, which perfrom specific functions.
What is a Plasma Membrane
The plasma membrane is the outermost boundary of the cell.
What makes up the structure of the plasma membrane
it contains lipids protein and carbohydates
What is different about the lipids in the plasma membrane
in the plasma membrane, lipids form a double layre in which many of the proteins float freely
What is the plasma membrane role in maintaining homeostasis
the plasma membrane is essential to cellular homestasis. it regulates the flow of the molecules and ions in and out of the cell. it is selectively permeable.
what are the five ways in which molecules can move through the plasma membrane
Diffusion
Carrier Proteins and Diffusion
Active Transport –molecules are also actively transported across the membrane
Endocytosis
Exocytosis
what is diffusion
the movement of the molecules from high to low concentrations
explain carrier proteins and diffusion
carrier molecules help water molecules diffuse through membranes
what is active transport
The movement of molecules across membranes with:
the aid of protein carrier molecules in the plasma membrane and energy supplied by ATP.
what is endocytosis and what are its two types
endocytosis: large molecules and cells are ingested by endocytosis
Two Types: phago and pino cytosis
What is phagocytosis
“cell eating.”
Process: In this process, a cell engulfs large particles or even other cells. The cell membrane extends around the target, forming a pocket that eventually closes off to create a vesicle.
what is pinocytosis
“cell drinking.”
Process: In this process, a cell takes in small amounts of fluid and dissolved substances. The cell membrane invaginates (folds inward) to form small vesicles that capture the fluid.
What is Exocytosis
it is when cells also regurgitate materials, releasing large molecules
what is Osmosis
The diffusion of water across the plasma membrane
Situation: two fluids with different concentrations of solute are separated by a selectively permeable membrane.
Result: the fluid will flow from one side to the other, moving down the concentration gradient.
In humans, osmosis helps regulate the concentration of fluid surrounding the cell.
What is the differnece between diffusion and osmosis
Diffusion is the movement of particles from a high to lower concentration. Osmosis is the diffusion of water across a membrane. Active transport moves particles from low to higher concentration.
what is the nucleus
The nucleus houses the genetic information that controls the structure and function of the cell.
what is the nucleolus
The nucleolus is a small, dense structure found within the nucleus of eukaryotic cells. Here are its key features:
Function: The primary role of the nucleolus is to produce and assemble ribosomes, which are essential for protein synthesis.
Composition: It is made up of RNA, DNA, and proteins. The nucleolus is not surrounded by a membrane, which makes it distinct from other cellular structures.
