AP Bio - Ch. 4-5 Test Study

What is the pink blob on the diagram?

Peripheral Protein

What is the purple thing?

Cholesterol

What is the red thing?

Glycolipid

What component in the fluid membrane mosaic model helps membranes resist fluidity at high and low temperatures?

Cholesterol

Which component in the fluid mosaic model that plays an important role in cell-cell recognition?

Peripheral Protein

What tonicity is line A?

Isotonic

What tonicity is line C?

Isotonic

What tonicity is line E?

Isotonic

What tonicity is line B?

Hypertonic

What tonicity is line D?

Hypotonic

Primary Structural Components of the cell membrane

Phospholipids and Proteins

At human body temperature (37C), cholesterol in membranes function to;

Make the membrane less fluid by restricting the movement of phospholipids

How do membrane phospholipids move?

Laterally along the plane of the membrane

Kind of molecule that can pass through a cell membrane most easily

Small Hydrophobic

Characteristic Feature of a Carrier Protein in a plasma membrane

Exhibits a specificity for a particular type of molecule

Molecule that diffuses through the lipid bilayer of a plasma membrane most rapidly

O2

Is this statement about diffusion correct?: It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.

True

Is this statement about diffusion correct?: It is a passive process in which molecules move from a region of lower concentration to a region of higher concentration.

False

Water can move quickly through the plasma membrane of some cells because

Aquaporin Channel Proteins

Mammalian blood contains the equivalent of 2% NaCl. Seawater contains an equivalent of 5% NaCl. What will happen if red blood cells are transferred to seawater?

Water will leave the cells, causing them to shrivel and collapse (Hypertonic)

Hypertonic Solution with Animal Cells

Water leaves, cell shrivels (crenation)

Hypotonic Solution with Animal Cells

Water enters, cell expands (lyse)

Isotonic Solution with Animal Cells

Equilibrium, Perfect for cell

Hypertonic Solution with Plant Cells

Water leaves, cell plasmolyzes

Hypotonic Solution with Plant Cells

Water enters, keeps cell shape, perfect for cell (turgid)

Isotonic Solution with Plant Cells

Equilibrium, Flaccid Cell

Submerging a plant cell in distilled water will result in;

The cell becoming turgid

Submerging a red blood cell in distilled water will result in;

Lysis of the cell

Does this membrane activity require energy from ATP hydrolysis? movement of sodium ions from a lower concentration in a mammalian cell to a higher concentration of extracellular fluid

Yes

What kind of transport is the phosphate transport system?

Cotransport

What is required for the sodium-potassium pump to transport potassium ions into an animal cell?

Energy from ATP

Proteins that allow the diffusion of ions across membranes in the direction of their concentration gradients are most likely;

channel proteins

The difference between pinocytosis and receptor-mediated endocytosis is;

Pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis does not.

When biologists wish to study the internal infrastructure of cells, they can achieve the finest resolution by using a;

TEM (transmission electron microscope)

What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?

Standard Light Microscopy

Large numbers of ribosomes are present in cells that specialize in producing which molecule?

Protein

If a treatment were available that would disrupt the nuclear lamina in living cells, what would you expect to be the most likely immediate consequence for the cell?

A change in the shape of the nucleus

Which structure is the site of the synthesis of proteins destined for export from the cell?

rough ER

The liver is involved in detoxification of many poison and drugs which structure is primarily involved in this process and therefore abundant in liver cells?

smooth ER

What is the function of the golgi apparatus?

Protein modification and sorting

Hydrolytic Enzymes must be segregated and packaged to prevent general destruction of cellular components. In animal cells, which organelle contains these hydrolytic enzymes?

Peroxisomes

Which organelle occupies much of the volume of a plant cell?

Central Vacuole

Which of the following correctly describes the pathway taken by a protein destined for secretion?

Rough ER → Transport Vesicle → Golgi Apparatus → Transport Vesicle → Plasma Membrane

A cell has the following molecules and structures: Enzymes, DNA, ribosomes, Plasma Membrane, chloroplasts, and mitochondria.

An archaeal cell or a plant cell

Archaeal Cell

unicellular prokaryotic microorganisms

Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen?

Peroxisomes

Thylakoids, DNA, and ribosomes are all found in:

Chloroplasts

The evolution of eukaryotic cells most likely involved:

Endosymbiosis of an oxygen using photosynthetic bacterium in a larger host cell--the endosymbiont evolved into mitochondria

Movement of vesicles in the cell depends on what cellular structures?

Microtubules and Motor Proteins

The extracellular matrix may influence animal cell behavior by communicating information from the outside to the cytoskeleton of the cell via which molecule or structure?

Integrin

Plasmodesmata in plant cells are most similar in function to which structures in animal cells?

Gap Junctions

Which structure plays a key role in maintaining the structural integrity of animal tissues?

Desmosomes and intermediate filaments

Which structure plays a major role in making skin water tight?

tight junctions

Which structure is not a part of the endomembrane system?

Chloroplast

Which structure is common to animal and plant cells?

Mitochondrion

Is this structure;function pair matched correctly?: microtubule;muscle contraction

Mismatched

Cyanide binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the;

Mitochondria

Free Water

Water that moves freely and is not attached to other molecules, able to pass through cell membranes.

Bound Water

Water that is attached to molecules inside a cell, like proteins, and doesn't move around easily.

Hypertonic

A solution with a higher concentration of dissolved substances than inside the cell, causing water to leave the cell.

Hypotonic

A solution with a lower concentration of dissolved substances than inside the cell, causing water to enter the cell.

Isotonic

A solution with the same concentration of dissolved substances as inside the cell, so water moves in and out at the same rate.

Osmosis

The movement of water through a membrane from an area of high water concentration to low concentration to balance things out.

Plasma Membrane

Selective barrier of the cell that controls what enters and exits, made of a phospholipid bilayer with embedded proteins.

Phospholipid Bilayer

A double layer of phospholipids that forms the core of cell membranes, with hydrophilic heads and hydrophobic tails.

Integral Proteins

Proteins embedded in the phospholipid bilayer, important for transport and communication across the membrane.

Peripheral Proteins

Proteins attached to the surface of the membrane, involved in signaling or maintaining the cell's shape.

Cholesterol

A lipid molecule that stabilizes the membrane's fluidity in varying temperatures by preventing it from becoming too rigid or too fluid.

Cytoskeleton

A network of protein filaments inside the cell that helps maintain shape, offers support, and facilitates movement.

Nucleus

The cell's control center, housing DNA and directing protein synthesis through the production of RNA.

Ribosomes

Structures responsible for protein synthesis, either free in the cytoplasm or attached to the rough endoplasmic reticulum.

Endoplasmic Reticulum (ER)

A network of membranes involved in protein (rough ER) and lipid (smooth ER) synthesis and transport.

Golgi Apparatus

An organelle responsible for modifying, sorting, and packaging proteins and lipids for delivery inside or outside the cell.

Lysosomes

Organelles containing digestive enzymes, responsible for breaking down waste materials and cellular debris.

Mitochondria

The powerhouse of the cell, generating ATP (energy) through cellular respiration by breaking down glucose and oxygen.

Chloroplasts

Organelles found in plant cells that carry out photosynthesis, converting sunlight, carbon dioxide, and water into glucose and oxygen.

Vacuole

A storage organelle that holds materials like water, nutrients, or waste; large central vacuole is found in plant cells.

Cell Wall

A rigid structure found in plant cells, fungi, and some prokaryotes, providing protection and structural support outside the plasma membrane.

Diffusion

Movement of molecules from an area of high concentration to low concentration without the need for energy.

Facilitated Diffusion

Movement of molecules across a membrane with the help of transport proteins, still not requiring energy.

Active Transport

Movement of molecules against a concentration gradient, requiring energy in the form of ATP and the use of transport proteins.

Endocytosis

Process by which cells take in large molecules by engulfing them, forming a vesicle from the membrane.

Exocytosis

Process by which cells expel large molecules by fusing a vesicle with the plasma membrane and releasing its contents outside.