Mastering Biology Chapter 4

What is the function of a bacterium's capsule? 1. protein synthesis 2. DNA storage 3. propulsion 4. protection 5. adhesion

4. protection A bacterium's capsule has a protective role.

Which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell? A. Mitochondrion. B. Chloroplast. C. Central vacuole. D. Golgi apparatus. E. Plasma membra

Answer: A. Mitochondrion. In both plant and animal cells, it's the mitochondria that convert chemical fuel into packets of chemical energy that can power the cell.

Which of the following describes the function of the chloroplast? A. The chloroplast creates internal pressure for a cell. B. The chloroplast functions as the site of lipid synthesis. C. The chloroplast stores compounds produced by the cell. D. The chloroplast serves as a protein manufacturing facility. E. The chloroplast converts light energy to chemical energy.

Answer: E. The chloroplast converts light energy to chemical energy. The chloroplast makes food for the plant cell by converting light energy to chemical energy.

_____ are found only in plant cells, but _____ are found in both plant and animal cells.

Central vacuoles; ribosomes

_________________________is the self-replicating material present in nearly all living organisms; it is the main constituent of chromosomes and the carrier of genetic information is the self-replicating material present in nearly all living organisms; it is the main constituent of chromosomes and the carrier of genetic information.

DNA

Function and structure of chloroplast

Found only in plant cells and some algae. Converts solar energy to chemical energy Organelle of Photosynthesis Produces O2 as a waste product.

Where is the genetic information of the cell stored?

Nucleus

Which organelle stores genetic information of the cell?

Nucleus

____________________is used in all steps of protein synthesis and carries the genetic information of many viruses.

RNA

works with mRNA to synthesize proteins

Ribsome

Which organelle is the site of lipid synthesis?

Smooth ER

What carries instructions for making proteins from the nucleus into the cytoplasm?

mRNA

Mitochondria appear in the greatest numbers in cells that are _____

metabolically active

Which of the following clues would tell you whether a cell is prokaryotic or eukaryotic?

whether or not the cell is partitioned into compartments by internal membranes

The round body that sits inside the nucleus of a eukaryotic cell and makes ribosomal subunits from proteins and ribosomal RNA is known as the

nucleolus

_______________is the most prominent membrane-bound organelle in eukaryotic cells, and it houses most of a cell's DNA.

nucleus

Lysosome

-Found in animal cells -Inside the cytoplasm of the cell -Looks like a really small ball -Breaks down waste. It can digest bacteria, food, and even itself if necessary

Smooth Endoplasmic Reticulum

-Found in both plant and animal cells -Cytoplasm of the cell next to the nucleus -Looks like coral, a long collection of tubes without dots -Transports nutrients, breaks down steroids, detoxifies organic compounds

Cell Membrane

-Found in both plant and animal cells -Surrounds the entire cell -Two phospholipid layers that are studded with protein and lipids that move freely (Fluid Mosaic Model) -The membrane is "selectively permeable" allowing certain molecules to enter or leave the cell

The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell. 1. plasma membrane 2. nucleoid region 3. ribosome 4. pili 5. cell wall

1. plasma membrane The plasma membrane is selectively permeable. Bacterial DNA is found in the nucleoid region.

In a bacterium, where are proteins synthesized? 1. ribosomes 2. nucleus 3. peroxisome 4. nucleoid region 5. capsule

1. ribosomes Ribosomes are involved in the manufacture of polypeptides (proteins).

1 meter = _____ centimeters

100 cm

________________are surface appendages that allow a bacterium to stick to a surface. 1. Ribosomes 2. Mitochondria 3. Fimbriae 4. Flagella 5. Cell walls

3. Fimbriae Fimbriae enable bacterial cells to stick to a surface._____

What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell? 1. capsule 2. pili 3. cell wall 4. flagella 5. nucleoid region

3. cell wall The cell wall is a rigid supporting structure

A 100 mm x 100 mm x 100 mm cell has a surface area that is _____ and a volume that is _____. When this volume is broken into many smaller cells, that are 10 mm x 10 mm x 10 mm, the sum of the surface areas of the smaller cells is _____ than the surface area of the initial cell.

60,000 mm2 ... 1,000,000 mm3 ... larger

Flagella and cilia are both composed of tubulin subunits. Despite this similarity, key differences exist between these two structures. For example, __________.

Flagella and cilia are both composed of tubulin subunits. Despite this similarity, key differences exist between these two structures. For example, __________.

Function and structure of Mitochondrion

Found in both animal cells and plant cells Produces CO2 as a waste product Organelle of cellular respiration Harvests chemical energy from food

Nuc

Found in both plant and animal

aid in the coordination of the activities of adjacent animal cells.

Gap junctions

Which of the following is part of the endomembrane system?

Golgi apparatus

. In both plant and animal cells, it's the________________________ that convert chemical fuel into packets of chemical energy that can power the cell.

Mitochondrion

Which technique allowed scientists to figure out that all cells, and not just muscle cells, contained actin filaments?

electron microscopy

Which of the following is a function of the central vacuole?

Storing compounds produced by the cell

D

The DNA-containing region of this bacterial cell is indicated by the letter _____. The figure shows the structure of a bacterial cell. Its surface is labeled

One function of the central vacuole in plant cells is facilitating cell growth: the central vacuole absorbs water and increases in size, expanding the volume and size of the plant cell while doing so. Animal cells, however, do not grow by this method. What is an essential difference between animal and plant cells that could explain how a plant cell can withstand this expansion of the central vacuole?

The plant cell wall provides a more rigid structure.

The plasma membrane is selectively permeable.

The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____. 1. A 2. B 3. C 4. D 5. E

What do the rough endoplasmic reticulum, Golgi apparatus, and lysosomes have in common?

They are constructed of interrelated membranes.

Mitochondria are found in ____

both plant cells and animal cells

are tightly coiled bundles of DNA and protein found in the nucleus of most living cells.

chromosomes

__ is the most prevalent glycoprotein in the extracellular matrix

collagen

The structural framework in a cell is the?

cytoskeleton

The primary role of _____ is to bind animal cells together.

desmosomes

What changes would you expect to see in the liver cells of someone suffering from chronic alcoholism?

increased levels of endoplasmic reticulum activity

Breaks down macromolecules using digestive enzymes

lysosome

Which of the following organelles breaks down worn-out organelles?

lysosomes

The cilia and flagella of eukaryotic cells are composed of ____

microtubules

When elongated, tube-shaped cells from the lining of the intestine are treated with a certain chemical, the cells sag and become rounded. The internal structures disrupted by this chemical are probably __________.

microtubules

Where in a cell is ATP made?

mitochondria

_______________________is the two-layered membrane that encases the nucleus of a eukaryotic cell, separating the nucleus from the cytoplasm.

nuclear envelope

A protein-lined channel in the nuclear envelope that regulates the transportation of molecules between the nucleus and the cytoplasm is called a

nuclear pore

Where is a bacterial cell's DNA found?

nucleoid region

Digestive cells produce and secrete many enzymes that break down ingested food. These cells have a large number of ribosomes ___

on the rough endoplasmic reticulum

What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?

plasma membrane

In plants, __________ are the cell junctions that allow the free exchange of small molecules that assist in communication. In animal cells, similar cell junctions are known as ________

plasmodesmata-gap junctions

Of the following organelles, which group is involved in manufacturing the substances needed by the cell?

ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum

One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by

ribosomes

You would expect a cell with an extensive Golgi apparatus to _____.

secrete a lot of material

Pancreatic cells produce large amounts of protein. About how many ribosomes would you expect there to be in a pancreatic cell?

several million

Where are lipids made in the cell?

smooth endoplasmic reticulum (ER)

Lysosomes are derived from __________ and function in __________.

the Golgi apparatus and rough endoplasmic reticulum ... digestion of worn-out organelles

Which of these cell junctions form a barrier to the passage of materials?

tight junctions