Cell Structures and Functions Flashcards
What are the taxonomic domains?
Bacteria, Archae, Eukarya
What are the similarities between eukaryotic and prokaryotic cells
One or more chromosomes, Ribosomes, Plasma Membrane, Cytoplasm
Where is DNA contained in Eukaryotic cells
The nucleus
Where is DNA in Prokaryotes
in the nucleoid, not membrane-bound
What is the difference in internal structure between eukaryotes and prokaryotes
Eukaryotes have a cytoplasm with specialized structures called organelles
Prokaryotes do not have compartmentalized structures
What is the size range of Eukaryotes and Prokaryotes
eukaryotes are larger (10-100um)
prokaryotes are smaller (~1 um)
What is the general role of the nucleus and ribsomes
genetic control
what is the function of the endomembrane system?
manufacturing, distribution, and breakdown
what is the general function of the mitochondria and chloroplasts
energy processing
what is the general function of the cytoskeleton
structural support, movement, communication
Describe the main function of the nucleus and what cells its found in
The nucleus is where most DNA is found and it acts as the genetic control center of the cell
it is found in both plant and animal cells
what are the various components of a nucleus?
The nuclear envelope, nucleolus, and chromatin
What is the nuclear envelope
it is composed of 2 phospholipid bilayers with pores that control the passage of materials in and out of the nucleus
it is attached to the endoplasmic reticulum
What is the nucleolus?
It is the site of rna synthesis
What is chromatin?
Thin fibers of DNA which carry all hereditary information + Protein
What is the Golgi Apparatus
It modifies proteins and membrane components/ materials into their finished forms
What is the general relationship of the endomembrane system
proteins and molecules move from the endoplasmic reticulum where they are synthesized through the golgi and finally out to the plasma membrane
What is the nucleus-endoplasmic reticulum complex?
it builds complex membranes, synthesizes proteins and prepares them for secretions. They are then sent to the golgi apparatus to be finalized
what are membrane-bound vesicles
they allow transport between organelles and the plasma membrane.
What is the endoplasmic reticulum?
a network of membranes sacs +tubes that are active in membrane synthesis, synthetic, and metabolic processes
Whats the difference between Rough and Smooth ER
Rough ER has ribosomes that modify proteins to be shipped
Smooth ER does not have ribosomes and is involved in the synthesis of lipids, fatty acids, phospholipids, and steroids
it also detoxifies molecules
What are lysosomes
They act as floating garbage disposals for cells, digesting and recycling cellular waste products and consumed materials
What are peroxisomes
they are oxidative organelles that rid the body of toxic substances that produce hydrogen peroxide as a by-product
what are Central vacuoles?
They are found in mature plant cells and hold organic compounds and water
What are flagella and Cilia
Cilia are short projections that beat swiftly to move fluid along and past a cell
Flagella are long, microtubule-based structures that move cells through their environment.
(Found in animals)
What is the mitochondria?
Mitochondria are found in both plant and animal cells
they harvest energy to be used for cellular functions
What are chloroplasts
they are the sites of photosynthesis and use light energy to build sugars ( found in plants)
What are the similarities in chloroplasts and mitochondria
they are not a part of the endomembrane system
they have a double membrane
contain their own DNA
have proteins made by free ribosomes
involved in energy metabolism
arose by endosymbiosis
What is the plasma membrane
all cells have a plasma membrane
they hold the contents of a cell in place, takes in food and nutrients, aids in building and exporting molecules, allows interactions with the environment and neighboring cells
What are ribosomes
granular bodies in the cytoplasm that convert genetic information into protein structure
what are cell walls
they protect and give shape to the cell
what is a centrosome
it is a structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles
What is the plasmodesmata?
They are specialized openings in the cell wall of plants that connect cytoplasm of adjoining cells
what is the purpose of the central vacuole in plants?
nutrient storage, waste management, predator deterrence, sexual reproduction, physical support
What is endocytosis
the transport of molecules into the cell
what is the role of intermediate filaments?
They have roles in cell shape and anchoring the nucleus and organelles
they are stable, not dynamic
What is the role of microtubules?
they have roles in intracellular transport, cell division, cell motility, and are highly dynamic
What are the extracellular components and what is its general role?
cell walls of plants
the extracellular matric of animals
and intercellular junctions
they help cells coordinate cellular activities
What are the functions of the extracellular matrix in animal cells?
Support, Adhesion, Movement, Regulation
What are the functions of cell walls in plants
maintain cell shape, protect cells, and prevent excess water uptake
What are junctions
they are facilitators of communication between neighboring cells
What do tight junctions do
they prevent the leakage of EC fluid across cells (animals)
what do desmosomes do
they fasten cells together in strong sheets (animals)
What do gap junctions do?
provide cytoplasmic channels from one cell to another (animals)
what do plasmodesmata do?
They are specialized openings in the cell walls of plants that connect the cytoplasm of adjoining cells
What are some other membrane proteins?
Receptor proteins for signal translation
enzymes (catalysts for biochem reactions)
cell-cell recognition
intercellular joining (tight junctions)
Attachment to the cytoskeleton and extracellular matrix
gap junctions (provide cytoplasmic channels from cell to cell)
desmosomes: fasten cells into tight sheets
What are the functions of mitochondria and chloroplasts
mitochondria created ATP through cellular respiration
cholorplasts create sugar energy through photosynthesis light energy
what is phagocytosis
lysosomes digest material derived from two other routes: phagocytosis and autophagy
