Cells Flashcards
what is the basic structural unit of a living organism
a cell
what is an organelle
a structure made of chemicals within a cell with a specific function
what type of organelle breaks and recycles damaged intracellular protein
proteasomes
what type of organelle makes ATP for the cell
mitochondria
what type of organelle catabolizes or “oxidizes” fats and organic compounds
peroxisome
Oxidize - oxisome
what type of organelle removes damaged cell substances
lysosomes
what type of organelle stores and packs secretory products and lysosomal enzymes
Golgi Apparatus
what type of organelle controls metabolism and protein synthesis and contains all the DNA
nucleus
what organelle aids in protection, support, entry and exit of items and substances
cell membrane
what organelle is the watery medium within the cell containing everything between the nucleus to the cell membrane
cytoplasm
what organelle synthesizes proteins for outside of cell use
rough endoplasmic reticulum
Aka
Rough ER
what organelle synthesizes fats (lipids) and aids in detoxification
smooth endoplasmic reticulum
Aka
Smooth ER
what organelle synthesizes proteins for cell use
free ribosomes
what organelle aids in strength and support of the membrane
cytoskeleton
what is the cytosol
the liquid substance within the cell
what is another name for the cytosol
intracellular fluid
what is another name for the cytoplasm
Intracellular fluid
in regards to a cell, which fluid is high in potassium ion (K+)
intracellular fluid
in regards to a cell, what is high in sodium ions (Na+)
extracellular fluid
what is interstitial fluid
the extracellular fluid between tissues
what are functions of the cell membrane
- semipermeable
- structure
- cell signaling and recognition
- homeostasis
what is the membrane made of
phospholipid bilayer, proteins, cholesterol, glycolipids and glycoproteins
which type of fluid is high in concentration of Potassium (K+) ions?
intracellular fluid
which type of fluid is high in concentration of Sodium (Na+) ions?
extracellular fluid
Is the inside or outside of a cell more negative?
the inside in more negative
(due to the phospholipid heads facing the inside)
what do integral (intrinsic) proteins do
these are proteins through the membrane and functions as tunnels to let certain items in and out
what do peripheral (extrinsic) proteins do
these are on either side of the membrane and they can be removed without damage to the membrane. they bind to proteins to let them in or out of the cell
what are functions of the proteins in a cell membrane
they function as receptors, markers, in identifying other cells, transport channels and as enzymes
what type of organic compound is cholesterol?
a steroid
what does cholesterol do for the cell membrane
gives strength and rigidity to the membrane
what are glycolipids
lipids/fats with a couple of sugars attached with a particular function for the plasma membrane
what are glycoproteins
proteins with a couple of proteins attached with a particular function for the plasma membrane
extensions of the cell membrane are known as ____
microvilli
what type of cell would have microvili
cells in the gastrointestinal tract (more surface area to aid in digestion and absorption)
what is a tight junction
a junction made of proteins that connect in a way where nothing can get through
very tightly packed
where are tight junctions found
in areas where you would not want fluid to escape
ex: cavity walls
what is a desmosome
a junction made of proteins where it is made where cells can’t be broken apart
Cells with desmorones appear to be welded together
what is the purpose of desmosomes and where are they found
to keep cells wound tightly together - they are “welded”
they are found in areas where cells need to stretch and to keep cells from ripping apart
Ex: skin
what is a gap junction and where are they found
a junction made of proteins that acts as a form of a bridge for cell to cell communication
they are found between 2 or more cells for communication
Ex: cardiac muscles
what is a cell inclusion
a clump of insoluble materials, melanin, pigments, glycogen, with some sort of protein attached.
what is the difference between MEMBRANOUS and NONMEMBRANOUS organelles
MEMBRANOUS have a phospholipid bilayer and the NONMEMBRANOUS does not
why do some organelles contain a membrane while others don’t
for function
what is a nucleus
an organelle within a cell containing all the DNA information to make proteins
Y/N
can cells be multinucleated
yes
skeletal muscle cells have many nuclei
can cells be anucleate or not have a nucleus
yes
red blood cells do not have a nucleus
why is the nucleus considered the “control center” of the cell
it contains all the necessary information to “code” for all proteins that may be needed for the cell
_____ is present when the cell is not dividing. it is made of DNA wrapped around histones.
*loose DNA
chromatin
____ are present when the cell is dividing. these structures consist of more tightly coiled chromatin connected at the centromere
*X shaped
chromosomes
what does the nucleolus do
make ribosomes for the cell
what does the mitochondrion do
uses oxygen to breakdown glucose to make ATP for the cell
what is the inner membrane of the mitochondrion called
the crista
what is the equation for cellular respiration
Glucose + Oxygen -> Water + ATP + Heat/Energy
OR
C6H12O6 + O2 -> H2O + ATP + Heat/Energy
** Glucose = Glucose + Phosphate + ADP
what are free ribosomes and what do they do
free ribosomes are ribosomes that are free in the cytoplasm
they make proteins that stay within the cell
what are fixed ribosomes and what do they do
fixed ribosomes are ribosomes attached to the rough endoplasmic reticulum and make proteins that will be used outside of the cell
how do the ribosome “know” what proteins to make
they derive from the nucleolus inside of the nucleus
proteins are made by combining the building blocks called ________ through a process called ________
amino acids
protein synthesis
what is the difference in structure of the smooth and rough endoplasmic reticulum
the rough ER contains fixed ribosomes while the smooth ER does not
what does the rough ER do
functions in protein synthesis
what does the smooth ER do
functions in fat/lipid synthesis, detoxification of drugs, carbohydrate metabolism, and calcium storage (in muscle cells)
what are some examples of steroids within the body
estrogen, androgens, testosterone, progesterone
what organelle is a membranous sac that functions in packaging secretions (proteins or other substances) for export
Golgi Apparatus
what happens to proteins as they move through the golgi apparatus
they get modified as needed and get secreted out in a vesicle
what is a secretory vesicle
a sack that connects to the membrane of a cell to get a protein or substance out of the cell
what is a transport vesicle
a sack that moves proteins and/or other substances from one organelle to another
what is the membranous organelle that contains digestive enzymes to destroy/”eat” dead or old cell structures, carbohydrates, proteins, etc
lysosome
what do lysosomes digest
carbohydrates, proteins, lipids, dead or worn out cell organelles/structures
what is the function of proteases in the lysosome
they hydrolyze peptides and proteins
what is the function of polysaccharides in the lysosome
to digest sugars
what is the function of lipases within a lysosome
to digest fat
what is the function of nucleases within a lysosome
to move DNA
what is the non membranous organelle for protein hydrolysis that contains proteases and help breakdown misfolded proteins and degrade proteins that are no longer needed
proteasomes
protea -> protein
what membranous organelle breaks down or “oxidizes” fatty acids so the cell can use them for ATP
**These are very important in the liver for detoxification
peroxisome
T/F
peroxisomes neutralize free radicals
free radicals: harmful chemicals
True
what organelles is a series of microfilaments and microtubules that weave through the cytoplasm therefore supporting the cell structure and help with transport
cytoskeleton
microtubules are hollow tubes of protein that help move organelles and compounds. microtubules are made of proteins called _________
tubulin
what are 3 structures made of microtubules
microvilli, centrioles, cilia
________ contain centrioles that are made of microtubules. they are non-membranous and come in pairs (2) and help move cell items when dividing
centrosomes
T/F
passive cell transport is a type of cell transport that uses ATP
False
what characteristics does a substance need to have in order to be easily transported across the cell memrane
small in size
items in positive charge move easily
fat soluble
what type of transport is the general movement of a substance from higher concentration to lower concentration and also requires substances to be lipid (fat) soluble and DOES NOT require ATP
passive diffusion
what type of cell transport requires a carrier/integral protein in the membrane to move across a membrane and also does not require ATP
**this type of cell transport moves water soluble substances
facilitated diffusion
what compounds can move through the membrane through facilitated diffusion
glucose, amino acids, certain ions, polar items, other simple sugars
the movement of water through a semipermeable membrane is called ________
osmosis
Y/N
does osmosis require ATP
no
what is the protein channel for water called
aquaporins
aqua=water
a ______ solution is when 2 solutions are being compared and have the same amount of solute to osmotic concentration
these include 0.9% saline solutions and 5% glucose solutions
isotonic
what type of solution is where the solution contains more solutes than what it is being compared to
**type of solution where water would move OUT of a cell and cause it to shrivel (crenate)
hypertonic
what type of solution is where the solution has less solute than what it is being compared to
**when water would move INTO a cell and cause it to burst (hemolysis)
hypotonic
what type of transport requires ATP
active transport
what is an example of active transport
sodium potassium pump
or
Na+/K+ exchange pump
in active transport, substances are moving _______ their concentration gradients
against
in which way does the pump pump sodium
out of the cell
in which way does the pump pump potassium
into the cell
in the sodium potassium pump, how many sodium and potassium are involved
3 sodium leaves the cell
2 potassium enters the cell
why does the sodium potassium pump require ATP
the breaking of ATP releases the energy needed to release and take in sodium and potassium
what is endocytosis
taking a substance into the cell
what are types of endocytosis
phagocytosis - cell eating - taking in solids
pinocytosis - cell drinking - taking in liquids
what is receptor-mediated endocytosis
endocytosis where a protein receptor in the membrane combines to something to trigger endocytosis
what is exocytosis
substance exiting the cell
exo = exit
why does exocytosis and endocytosis require ATP
they both move substances against their concentration gradient
why can endo- and exocytosis be referred as “bulk transportation”
because it can move a lot of items into/through the membrane through vesicles
_______ is the process resulting in two (2) identical daughter cells
mitosis
T/F
each daughter cell resulting from mitosis contain identical DNA
True
how many chromosomes does the human body have
46 chromosomes
what are the three (3) phases of interphase
G1 phase, S phase, and G2 phase
what happens at the G1 phase
the cell is growing - it is developing enzymes and duplicating the organelles
what happens during S phase
the cell is synthesizing the proteins necessary for cell division, the DNA is duplicating along with all the organelles
what happens during G2 phase
the cell is preparing to divide - it is making the enzymes necessary for cell division
what are phases of mitosis
prophase
metaphase
anaphase
telophase e
what are phases of mitosis
prophase
metaphase
anaphase
telophase
what happens in prophase
chromatin condenses to make chromatids to then have 2 homologous chromatids be connected in the center by centromeres to make a chromosome
the nuclear membrane and nucleolus start to disintegrate and breakdown
the centrioles start to make spindle fibers and migrate to either side of the cell
what happens during metaphase
the chromosomes line up at the equator
the spindle fibers/mitotic spindle start to connect to either side of the cell at the centrioles or at the centromeres to separate the chromosomes
what happens during anaphase
the centromeres start to split due to the spindle fibers shortening therefore causing the chromosomes to split into their corresponding chromatids
the cleavage furrow starts to form
what happens during telophase
the chromatids start to form back into chromatin
the nuclear membrane and nucleolus start to reform
cleavage furrow starts to become more prominent
what is cytokinesis
the separation of the cytoplasm that overlaps with mitosis
Division of the cytoplasm
in which phase of mitosis does cytokinesis start
anaphase - the cleavage furrow is used to later separate the two cells during cytokinesis
what cells DO NOT undergo mitosis
skeletal muscle cells, cardiac cells and neurons
which cells rapidly undergo mitosis
epithelial cells (skin cells) and cells within the gastrointestinal (GI) tract
what is contact inhibition
where cells stop dividing/growing when they touch another cell
Y/N
do cancerous cells maintain contact inhibition
No
what is a benign tumor
a tumor that lost contact inhibition but only stays in the place where it formed
what is a malignant tumor
a tumor that has started to lose its contact inhibition and start to spread rapidly
what does it mean for a tumor to metastasize
the cancer cell broke away from the malignant tumor and has spread through the lymphatic system or blood stream and is now starting to “invade” or infect other tissues
_______ is the process where sperm and egg are made. cells derived from this contain half the number of chromosomes (haploid) than other human cells
meiosis
what are homologous chromosomes
2 chromatids or similar nature
1 from mom and 1 from dad
