Test 2: paper review Flashcards
What is the site of protein synthesis
ribosomes
what digests worn-out cell parts and invading bacteria
lysosomes
what produces a usable form of energy for the cell
Mitochondrion
What transports materials within the cell
vesicles
what organelle controls all cell functions
nucleus
What makes proteins for transport out of the cell
rER
where is the site where ribosomes are made
nucleolus
What organelle produces lipids
sER
Where is DNA stored
nucleus
What is the structure that controls what enters and exits the cell
cell membrane
what contains powerful enzymes for detoxification
sER
composed of a phospholipid bilayer
membrane
do all cells in the human body have a nucleus? Do any have more than 1?
No, red blood cells have none and skeletal muscles have multi
Name 2 organelles with double membranes
chloroplast and mitochondrion
some cells, such as the neuron, produce protein-based neurotransmitters and use large quantites of ATP to send nervous signals throughout the body. which ORGANELLES would you expect ot find large quantities.
Mitochondrion
What does the fluid mosaic model describe the plasma membrane consiting of
diverse proteins embedded in a phospholipid bilayer
most of the functions of a cell membrane, including transport and enzmatic function, are preformed by:
proteins
Relaying a message from a membrane receptor to a molecule that performs a specific function within a cell occurs when
a signaling molecule binds to a protein that extends to the outside of the cell
Plasma membranes are semipermeable. This means:
the plasma membrane allows some substances to enter or leave a cell more easily than others
Small, nonpolar, hydrophoic molecules such as fatty acids ______________ thorough a membranes lipid bilayer
easily pass thru the layer
Which of the following would have the most trouble crossing through a biological membrane by diffusing through the lipid bilayer?
O2
CO2
Na+
a small nonpolar molecule such as butane
Na+
Oxygen crosses the plasma membrane via ______
simple diffusion
Is diffusion a result of the thermal energy of atoms and molecules
Yes
Does diffusion require energy
no
does diffusion occur when particles spread from areas where they are less concentrated to areas where they are more concetrated
No
Does diffusion occur even after equilibrium is reached and no net charge is apparent?
Yes
Diffusion does not require ATP. therefore atp diffusion is concedered _______ transportation
passive
When 2 aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place, the water will:
move from the side with lower solute concentration to the side with higher solute concentration
Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. the presence of these organelles tells you that the enviroment is:
is hypotonic to the protozoan
A cell that has neither a net gain of water nor net loss of water when it is immersed in a solution must be ______ to its environment
isotonic
In a hypotonic solution an animal cell will
lyse
You are adrift in the Atlantic Ocean and, being thirsty, drink the surrounding seawater. As a result, you ______
dehydrate yourself
Facilitated diffusion across a biological membrane requires _______ and moves a substance _______ its concentration gradient
transport proteins; down
The molecules responsible for membrane transport are
proteins
what do aquaporins do
allow water to cross the plasma membrane via facilitated diffusion
What moves a solute against its concentration gradient
active transport
Which of the following is a typical feature of an ATP-driven acitve transport mechanism
The transport protein must cross to the correct side of the membrane before the solute can bind it
The trasport protein is irreversibly phosphorylated as transport takes place
The transport protein catalyzes the conversion of ADP to ATP
The solute moves against the concentration gradient
The trasport protein is irreversibly phosphorylated as transport takes place
Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. This enzyme is a protein. Which of the processes could be responsible for its secretion
exocytosis
The process of a white blood cell engulfing a bacterium is
phagocytosis
Kinetic energy differs from chemical energy in that
kinetic energy is the energy of a moving object, whereas chemical energy is th potenital energy of molecules
which law of thermodynamics states energy cannot be created or destroyed
1st
Which of the following direct energy transfers is impossible in living systems:
Light energy to chemical energy
Chem to kinetic
Light to potential
Heat to light
Heat to light
Which of the following processes is endergonic
Burning wood
synthesis of glucose from CO2 & water
Breakdown of glucose
Cellular respiration
synthesis of glucose from CO2 & water
What is the basic difference btw exergonic and endergonic reactions
exergonic releases energy while endergonic absorbs it
Does ATP release energy when one phosphate group leaves it?
yes
how many phosophate groups make up ATP
3
When an enzyme catalyzes a reaction, it ______ the activation energy of the reaction
lowers
Substrates bind to an enzymes ____ site
active
What are the 4 structures that plant cells have that animal cells do not
cell wall, chloroplasts, plastids, and a central vacuole
What are the 6 structures in the endomembrane system? how are they related
Nuclear envelope, ER, Golgi, Lysosomes, Vesicles, Membrane, work together to package and transport lipids/proteins
4 functions of the smooth ER
synthesis of lipids, steroid hormones, the detoxification of harmful metabolic byproducts and the storage and metabolism of calcium ions within the cell.
What are the 2 types of endocytosis
pinocytosis and phagocytosis
Name the 3 types of protein fiber in cytoskeleton
Microfilaments, intermediate filaments, and microtubules
What is a fluid mosaic model
The fluid mosaic model explains various characteristics regarding the structure of functional cell membranes
What is osmosis
the moement of water down its concentration gradient
What is the difference btw exergonic and endergonic? examples?
Exergonic breaksdown molecules while endergonic builds them. Endergonic takes lower potential energy and makes high. Exer takes high potential energy and creates low energy products
Is exergonic catabolic or anabolic
catabolic
Is endergonic catabolic or anabolic
anabolic
