Chapter 6 (Endomembrane system) Flashcards
What are cells?
the simplest collection of matter that lives
What are the two types of cells?
eukaryotic and prokaryotic
Humans have which type of cell?
eukaryotic cell
ALL types of cells share which common features?
plasma membrane to the different interior from exterior
cytosol that keeps the organelles floating around
chromosomes that store genetic material
ribosomes which are the unit that creates proteins
Prokaryotic cells are characterized by having…
NO nucleus
DNA that is kept free in one area called the nucleoid region
NO membrane-bound organelles
Eukaryotic cells are characterized by having
membrane-bound nucleus and organelles, they are generally much larger than prokaryotic cells
What is the endomembrane system?
one interconnected system of membrane consisting of the nucleus, endoplasmic reticulum, and the Golgi apparatus, and lysosomes
Where are most of the DNA held in the cell?
the nucleus
DNA is found in what state in the nucleus?
as chromatin, strings of protein
What is the condensed version of chromatin called?
chromosomes
Where is the nucleolus?
within the nucleus
What is the nucleolus?
the site of RNA synthesis
What is the nuclear envelope?
it encloses the nucleus, has pores, has a nuclear lamina
What are the pores in the nuclear envelope for?
regulation of entry and exist of genetic molecules mostly in the form of RNA
What is the nuclear lamina?
it is the proteins that help structure and network to maintain the shape of the nuclear envelope (crosshatches)
Where is the endoplasmic reticulum found?
attached to the nucleus, for the ease of genetic transfer
What are the two types of endoplasmic reticulum?
smooth and rough
What does the rough ER do and have?
the rough ER has proteins bound to it
it reads genetic material from the nucleus and forms proteins
What does the smooth ER do and have?
no proteins bound to it
assemblers phospholipids for the membrane
generates steroid lipids
stores calcium
What does the ER receive?
raw protein products getting filtered into it
What happens to the raw protein products after they go through the ER?
distributed to transport vesicles leading to the Golgi apparatus
What does the Golgi apparatus consist of?
flattened membrane sacs
What is the purpose of the Golgi apparatus?
receiving raw material at the cis-face side (inward curve) and move throughout the layers to get process until the trans face
What are the functions of the Golgi apparatus?
sorts and package into vesicles
makes modifications so that materials go to the right place
modify ER products
delivers to different areas using vesicles
What are lysosomes?
membrane vesicles aka the molecular stomach
What is the purpose of a lysosome?
to digest molecules using enzymes
What are peroxisomes?
membrane vesicles that ARE NOT PART OF THE ENDOMEMBRANE SYSTEM
What is the purpose of peroxisome?
use oxygen to breakdown components and metabolizes lipids
What are the energy-producing organelles?
mitochondria and chloroplasts
____ and ____ are called autonomous organelles because _____
the mitochondria and chloroplast are called autonomous organelles because they have their own DNA and divide themselves
The mitochondria is unique because it has 2 ____ of its own
The mitochondria are unique because it has 2 membranes of its own
What are the mitochondria for?
cellular respiration, produce energy
What is the intermembrane space?
space between the two membranes of a mitochondrion
What is the matrix?
the space inside a mitochondrion
The inner membrane of a mitochondrion is folded because
there is more surface area for chemical energy conversion of ATP
Where are chloroplasts found?
in plants and algae
What do chloroplasts use for energy conversion?
light energy
What catches the light energy in the chloroplasts?
chlorophyll
What is the cytoskeleton?
protein network of fibers extending throughout the cytoplasm
What does the cytoskeleton do?
supports cell and helps maintain shape, regulation of movement
What are the components of the cytoskeleton?
microtubules, microfilaments, intermediate filaments
What are microtubules?
hollow tube aka tracks for vesicles movement like a highway road
What are microfilaments?
globular filaments that are rod like
What is the thinnest component of the cytoskeleton?
microfilaments
What are intermediate filaments?
ropes of proteins that are hard to break down and are tightly packed that are able to withstand stress
Motor proteins use this to move in one certain direction
motor proteins use microtubules to move in one certain direction (growing is positive and negative is anchored)
What do microtubules produce?
structures for mitosis to occur, cilia, and flagella
What is a centrosome?
microtubule organized center, contains a pair of centrioles
What are microfilaments used for?
push and pull of plasma membrane by forming the cortex
What transitions do microfilaments make?
sol-gel transitions (solid to fluid)
Where can you find microfilaments?
muscles, near the inner part of plasma membrane
What is the outside of the cell called?
extracellular matrix (ECM)
What is the ECM made of?
proteins excreted from cells, structures outside the cells (fibronectin)
What is fibronectin?
an outside protein that connections the membrane to the extracellular environment
What is proteoglycan?
protein+carbohydrate that helps connect external environment for support, adhesion, movement, and regulation
What are intracellular junctions?
neighboring cells in tissues or organ systems often adhering, interacting, and communicating through physical contact
What are some types of intracellular junctions?
tight junctions, desmosomes, gap junctions, and plasmodesmata
What are tight junctions?
line of demarkation, separates environments
What are desmosomes?
an anchor, two cells adhere and become a unit
What are gap junctions?
pores between two different cells for communication
What are plasmodesmatas?
they are found in plant cells, have to communicate through cell walls and plasma membranes (a type of gap junction)
What is the nucleus for?
primarily for messaging, copying DNA, and converting to RNA, holding genetic material
What protein makes microtubules?
tubulin
What does tubulin (protein) make?
microtubules
What is the structure of microfilaments under the plasma membrane called?
the cortex
