biology exam #2

how are substances brought across the membrane?

-passive transport *simple diffusion( movement from an area of high concentration to an area o low concentration

function of plasma membrane

-protect the cell from its surroundings -regulates what goes in and out of the cell -selectively permeable -certain substances are allowed to pass through freely

membrane proteins Function

-responsible for moving substances across the membrane and communicating with other cells

membrane proteins examples

-transport protein:(doorway) form channels or acts as carriers -receptor proteins:(receive-lock on door)when a specific molecule binds to them it triggers a specific cellular response -recognition protein: serve as cell ID tags or cell surface attachment sites

Cells are more like a _____ canned drink than a _____ canned drink.

12oz, 40 oz

structure of plasma membrane

2 layers of phospholipids -hydrophilic heads(outer) -hydrophobic "tails"(inner)

Plasmodesmata are cell junctions in plant cells that are similar in function to Select one: a. gap junctions in animal cells. b. tight junctions in animal cells. c. adhering junctions in animal cells. d. the cuticle in plant cells. e. stomata in plant cells.

A. gap junctions in animal cells

Four of the five items listed below are cytoplasmic organelles. Select the exception. Select one: a. nucleolus b. mitochondrion c. ribosome d. Golgi body e. chloroplast

A. nucleolus

As a cell increases in size its ___ increases faster than its ___. Select one: a. volume, surface b. surface, volume c. surface, size d. membrane, cytoplasm e. none of these

A. volume, surface

Which of the following are NOT found in prokaryotic cells? Select one: a. ribosomes b. membrane-bound organelles c. polysaccharide capsules d. cell walls e. flagella

B. membrane-bound organelles

Which of the following organelles is correctly matched with its function? Select one: a. nucleus: lipid synthesis b. ER: heredity c. Golgi bodies: packaging d. mitochondria: digestion e. chloroplasts: storage of lipids

C. Golgi bodies:packaging

Four of the five answers listed below are types of intercellular connections. Select the exception. Select one: a. tight junctions b. gap junctions c. plasmodesmata d. adhering junctions e. plasmalemma

C. plasmodesmata

Which is the correct sequence of polypeptide transport in the secretory pathway? Select one: a. plasma membrane >>> Golgi bodies >>> ER >>> ribosome b. plasma membrane >>> ER >>> Golgi bodies >>> ribosome c. ribosome >>> Golgi bodies >>> ER >>> plasma membrane d. Bound ribosome on Rough ER >>> Golgi bodies >>> plasma membrane e. Golgi bodies >>> ribosomes >>> ER >>> plasma membrane

D

Which of the following contain enzymes, are the main organelles of intracellular digestion, and can digest whole cells? Select one: a. Golgi bodies b. vesicles c. peroxisomes d. lysosomes e. endoplasmic reticula

D. lysosomes

Cilia and flagella are most similar in which of the following? Select one: a. length. b. the kinds of cells that have them. c. the number that cells usually have. d. made from microtubules e. their location along the cell's periphery.

D. made from microtubules

All of the following are found in both plant and animal cells EXCEPT Select one: a. nuclei. b. ribosomes. c. Golgi bodies. d. plastids. e. vacuoles.

D. plastids

Which of the following are sometimes referred to as rough or smooth depending on structure? Select one: a. Golgi bodies b. plasma membrane c. nuclear membrane d. lysosomes e. endoplasmic reticula (ER)

E. Endoplasmic Reticula (ER)

Only plant cells possess Select one: a. a central vacuole. b. chromoplasts. c. amyloplasts. d. chloroplasts. e. all of these

E. all of these

Prokaryotes A. have nuclide regions B. are unicellular C. may have cell walls D. are either bacteria or archeans E. all of these

E. all of these

the organelle that pinches off portions of its membrane to form a compartment used for storage or transport is the

Golgi body

Who coined the term "cell"?

Robert Hooke

the idea that all living cells arise from preexisting living cells was proposed by

Rudolf Virchow

the activity of which organelle helps detoxify drugs?

Smooth ER

Why are cells so small?

a call needs to have more surface area than volume in order to obtain nutrients and eliminate waste efficiently with the environment

Which of the following are the primary structures that package cellular secretions for export from the cell? Select one: a. Golgi bodies b. ribosomes c. mitochondria d. lysosomes e. endoplasmic reticula

a. Golgi bodies

Starch is stored in plant organelles called

amyloplasts

Which animal cell junction is correctly matched with its function? Select one: a. adhering; allows rapid flow of substance b. tight; holds cells together c. gap; connects cytoplasm of adjoining cells d. adhering; seals adjoining cells e. gap; prevents passage of materials

c. gap; connects cytoplasm of adjoining cells

Which of the following are the primary cellular sites for the capture of energy from carbohydrates? Select one: a. Golgi bodies b. ribosomes c. mitochondria d. lysosomes e. endoplasmic reticula

c. mitochondria

Which of the following contain enzymes used in the breakdown of glucose and generation of ATP? Select one: a. Golgi bodies b. ribosomes c. mitochondria d. lysosomes e. endoplasmic reticula

c. mitochondria

the fluid-filled sac that may store waste, ions, or water in plant cells and that is also involved in growth and turgor pressure is the

central vacuole

All of the following are tenets of the cell theory EXCEPT ___. Select one: a. all organisms consist of one or more cells. b. the cell is the smallest unit that retains the characteristics of life. c. all cells come from pre-existing cells. d. all cells have a nucleus e. none of the above

d. all cells have a nucleus

The pseudopodia of amoebas are produced by action of ____ and motor proteins. Select one: a. myosin b. microtubules c. intermediate filaments d. microfilaments (actin) e. all of these

d. microfilaments (actin)

Photosynthesis is associated with all of the following EXCEPT Select one: a. chloroplasts. b. plastids. c. grana. d. thylakoid. e. lysosomes

e. lysosomes

which of the following are sometimes referred to as rough or smooth depending on structure?

endoplasmic reticulum

Cholesterol

makes the bilayer stronger, more flexible, and less permeable to water- soluble substances such as ions and simple sugars

The Cytoskeletal element that is a guide wire or track for vesicles to follow

microtubule

what cell feature is absent in bacterial cells?

nucleus

The major component of cell membranes

phospholipids

Which organelle is involved in protein synthesis?

rough endoplasmic reticulum