The Organelles Flashcards
The internal framework of a cell.
Provides shape, support, and scaffold for suspending and moving organelles.
Cytoskeleton
Gives cells a plasticity, or fluidity, that allows them to change shape or move organelles quickly.
Cytoskeleton
What are the 3 types of protein structure
- Microfilaments
- Intermediate Filaments
- Microtubules
The thinnest cytoskeletal structures
Microfilaments
Much stronger than microfilaments
Intermediate Filaments
Used as tracks for organelle movement.
Instrumental in chromosome movement during cell division.
Microtubules
Protect the cell from mechanical stresses.
Intermediate Filaments
Responsible for cellular locomotion, muscle contractions, movement during cell division.
Establish the basic shape and strength of the cell.
Microfilaments
Long, whip-like structures that propel cells forward.
Flagella
Give an example of a Flagella
Sperm: the only human cell that moves by flagellum
Shorter extensions that look like hairs or eyelashes.
More common in the human body than the flagella.
Cilia
They beat synchronously to move mucus across the surface of the cell or to circulate the extracellular fluid to increase diffusion – “power stroke”
Cilia
Networks of folded membranes that lie within the cytosol.
Endoplasmic Reticulum
What are the two types of ER in human cells?
- Rough Endoplasmic Reticulum
- Smooth Endoplasmic Reticulum
A processing and sorting area for proteins synthesized by ribosomes that stud its outer membrane.
Rough Endoplasmic Reticulum (RER)
Responsible for the synthesis of fatty acids and steroid hormones.
Has no attached ribosomes.
Smooth Endoplasmic Reticulum (SER)
Small organelles composed of protein and ribosomal RNA that serve as protein factories, synthesizing proteins that may be included in other organelles or in the plasma membrane itself, or are exocytosed through secretory vesicles.
Ribosomes
True or False
In both RER and SER, the end product is a vesicle filled with product ready for the next step in processing—to the cell membrane for exocytosis or to Golgi complex for further packaging.
True
Usually found near the end of the SER and resembles a stack of pancakes called SACCULES.
Golgi Complex/ Apparatus
Slightly curved, with concave and convex faces
Saccules
Used to transport substances within a cell
Circular Vesicles/ Transfer Vesicles
Face the Endoplasmic Reticulum (ER)
Concave portions
Face the plasma membrane.
Convex portions
Completes the processing of proteins and fatty acids, readying the products for the use in other organelles or in the cell membrane
Golgi Complex/ Apparatus
Chemical packages produced by the Golgi complex that contain hydrolytic enzymes
Lysosomes
Powerful enough to digest an entire cell from the inside.
Responsible for autolysis or “self-breaking”
Lysosomes
to break open or break apart
Lyse
True or False
Lysosome + endocytotic vesicle = pours its contents into the vesicles
True
It contains a cell’s genetic library and is usually the largest organelle in a cell.
Nucleus
Nucleus is covered by a phospholipid membrane, called?
Nuclear envelope
______ complete phospholipid bilayers surrounding the nucleus, whereas the cell membrane is a ___________.
Two; Single bilayer
The envelope is punctuated by ___________, which allows molecules to enter and exit the nucleus.
Nuclear pores
The _________ in the nucleus is analogous to the cell’s library, which is “read” by RNA
DNA
After RNA makes a perfect impression of the DNA, it leaves the nucleus and serves as ______
Templates for proteins
Its a process of forming RNA copies of nuclear DNA
Also means to “write elsewhere”
Transcription
Thread-like DNA within the nucleus of an active cell (neither resting nor dividing).
Chromatin
Condensed and coiled chromatic threads before cell division.
Chromosomes
Darker areas of chromatin found in the nucleus of most active cells
Nucleoli
True or False
Within nucleoli, ribosomal RNA is produced and ribosomes are assembled.
True
Bean-shaped organelle
Has smooth outer membrane and folded inner membrane
Mitochondria
Convert digested nutrients into usable energy for the body, in the form of ATP.
ATP forms within the inner membrane of the mitochondrion
Mitochondria
Folded inner membrane with folds called ________ (hallmark of mitochondria)
Cristae
