Test #2

cells that experience high mechanical stress, like heart cells, typically connect to one another using a ___ junction allowing stress to be evenly distributed to a larger area.

anchoring

A cell you view under a microscope has a cell wall but no nucleus. The cell you are viewing could be a

bacterium

all steroid hormones derive from

cholesterol

All steroid hormones are hydrophobic. Where would you expect the receptor proteins for these hormones to be located? In the ____ of a cell.

cytoplasm

The fragrance of bread baking in a kitchen spread to other rooms by

diffusion

Cells in the liver typically acquire cholesterol by receptor-mediated

endocytosis

You observe a vesicle moving toward the plasma membrane from inside of a cell. Once it reaches and fuses with the plasma membrane, you will most likely see and example of

exocytosis

a membrane that is selectively permeable causes damage to the cell by allowing solutes to enter and leave the cell indiscriminately

false

mitochondria produce most of the energy used in a bacteria cell. True or False?

false

steroids are unable to cross plasma membrane

false

the subunits of eukaryotic ribosomes are 30s and 50s

false

To coordinate the contraction of the numerous muscle cells that form the hear, signals must travel rapidly between muscle cells.In order to allow this rapid communication, muscle cells in the heart are connected by

gap junctions

Insulin is produces only by a single organ the pancreas yet insulin is used to move glucose from the blood stream into cells and all over the body. What aspect of hormones makes it possible for insulin to work throughout the body.

hormones are long-range signaling molecules

you observe a cell swelling until it bursts. you just saw

hypotonic solution

signaling molecules can affect a cell from the outside by interacting with specific receptors that are located

in the plasma membrane

When the solute concentration outside of a cell is equal to the solute concentration inside of the cell, the cell is an_____ solution

isotonic

Which of the following is not a function of the plant vacuole

productions of ATP

Ribosomes a very small non membranous organelles associated with the synthesis of

protein

The membrane known as the ____ contains light capturing pigments like chlorophyll

thykaloid

Epithelial tissue in animals provides a barrier against the invasion of bacteria into they body. Which of the following is most likely responsible for creating tight enough barrier to prevent the passage bacteria

tight junctions

Which of the following structures is not found in all types of cells

nucleus

the_____ has a double membrane but no cristae

nucleus

The passive moment of water across a selectively permeable membrane is called

osmosis

During the process of _____ is given off as a by-product

oxgen

change shape upon binding to specific external molecules and then release the molecule on the other side of the membrane

passive carrier proteins

a white blood cell at the site of a puncture wound engulfs a large cluster of bacteria this is an example of

phagocytosis

What components of the plasma membrane of an animal cell would you find at its innermost surface directly exposed to the cytoplasm

phospholipid heads and proteins

The boundary structure that physically defines a cell is the

plasma membrane

Which of the following are found in plants

plasmodesmata

Which of the following would supply energy directly to an active carrier protein

ATP

Which of the following statements is false

Actin filaments define the paths for vesicle movement with the cell

Which of the following statements is false ?

Eukaryotes use RNA as the hereditary genetic material

bind to cell surface receptors and do not enter cells

Hydrophilic signaling molecules

Protist use cilia to move within their habit, but ciliated human cells like those in the bronchi are always anchored to one another and to an extracellular matrix; what benefit does cilia provide these cells?

all of the above

Using an electron microscope you notice an organelle that consists of stacks of membranes and appears to be producing vesicles. This organelle is most likely

a Golgi apparatus

The inner membranes of both mitochondria and chloroplasts are folded into various arrangements. What is the advantage of having a folded membrane rather than a simple interior membrane that follows the same oval shape as the exterior membrane

The folds allow for more surface area for the chemical reaction that occur across the inner membranes

Imagine examining a cell using a light microscope; a prokaryote could be distinguished from a eukaryote by the absence of

a nucleus

Which of the following statements is false?

The plasma membrane is the storehouse for each cells genetic information

is the where lipids destined for other cellular compartments are manufactured

The smooth endoplasmic reticulum

Which of the following statements is true of chloroplasts

They capture energy from sunlight

The plasma membrane of a cell and the membrane boundaries of organelles such as mitochondria and chloroplasts serve similar functions. What is one of the main functions of the membranes of both cells and organelles?

They keep reactants near each other to speed biological reactions

Which of the following would be the best analogy for the function of the Golgi Apparatus

a worker in a factory who places labels on products and then packs them into a shipping box

Muscle cells require high concentrations of calcium to function properly. As a result, the cells use ________ transport to move calcium from areas of low concentration outside the cell into the cytoplasm

active

the concentration of glucose inside of a cell is higher than the concentration outside of that cell, yet glucose continues to enter the cell. This is an example

active transport

The relative abundance of a specific organelle is often predictable when cell function is considered; for example, the _____ could be expected to contain more lysosomes than an average cell

cell that roam around your body engulfing and consuming bacteria

Which of the following components contribute to the structure of the cytoskeleton of a cell?

microtubules and actin filaments

Your muscle cells need large amounts of ATP to function in the movement of your body. Which of the following organelles would you expect to be especially abundant in muscle cell?

mitochondria

The boundary that surrounds the contents of the nucleus is the

nuclear envelope

The region of the nucleus where ribosome production begins

nucleolus

Which of the following could not easily diffuse across a plasma membrane

sugar molecules

Lysosomes are organelles responsible for the breakdown of macromolecules. Why is it useful to have the lysosomal reactions compartmentalized rather than allowing them to take place freely in the cytoplasm of the cell

the absence of lysosomes would cause animal cells' vacuoles to burst

Which of the following works like a propeller

the prokaryotic flagella

The word fluid in the term fluid mosaic model refers to the fact that

the proteins within a membrane freely move around

Which of the following statements about hormones is false

they are not used by multicellular organisms

Channel proteins require energy for transporting molecules across the plasma membrane

true

Gap junctions allow large molecules to move from cell to cell

true

Ligand is another name for signaling molecules

true

The pH of a solution is 10. This means the solution is basic

true

microtubules are composed of tubulin monomers

true