Bio 101: A tour of the Cell: mastering

Which of the following statements about cellular metabolism is false?

Cellular metabolism occurs in animal but not plant cells.

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

Central vacuoles; ribosomes (Central vacuoles are found only in plant cells. Ribosomes are found in both plant and animal cells.)

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

Storing compounds produced by the cell (One of the functions of the central vacuole is to store compounds produced by the cell.)

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

They are constructed of interrelated membranes. ( Each of these organelles is a member of the endomembrane system and is constructed of the same type of membrane.)

Can you label the structures of an animal cell?

a) cytoskeleton b) ribosomes c) nucleus d)smooth ER e) cytosol f) Golgi apparatus g) rough ER h) mitochondrion I) plasma membrane

Can you label the structures of a prokaryotic cell?

a) fimbriae b) nucleoid c) plama membrane d) cell wall e) capsule f) flagella g) bacterial chromosome h) ribosomes

Can you label the structures of a plant cell?

a. central vacuole b. cell wall c. chloroplast d. Golgi apparatus e. smooth endoplasmic reticulum (ER) f. rough endoplasmic reticulum g. nucleus h. mitochondrion

The membranous compartmentalization of a cell

allows different chemical conditions to be maintained in different parts of the cell.

Mitochondria are found in _____.

both plant cells and animal cells ( Mitochondria are found in nearly all eukaryotic cells.)

Tay-Sachs disease

causes an accumulation of lipids in brain cells.

The nucleoid region of a prokaryotic cell

contains the cell's DNA.

The function of the chloroplast is to _____.

convert light energy to chemical energy (The function of the chloroplast is to convert light energy from the sun to the chemical energy of a glucose molecule.)

the Plant cell wall

is a protective structure made of cellulose fibrils. ( The cell wall is a structure that protects the plant cell and is made of cellulose fibrils.)

Part complete Protein synthesis requires the use of mRNA, which

is translated by the ribosomes into the amino acid sequences of proteins.

The maximum size of a cell is limited by _____.

its need for enough surface area to make exchanges with its environment ( Because volume increases at a faster rate than surface area, large cells have proportionately less plasma membrane surface area.)

The cells of a person with adrenoleukodystrophy (ALD) swell with a buildup of fatty acids. In other words, fatty acids are not being broken down. Which organelle is most likely failing to function correctly?

lysosome ( This organelle functions to remove unwanted or unneeded material from the cell.)

Tay-Sachs disease results from the malfunction of

lysosomes

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

lysosomes (Lysosomes contain digestive enzymes and break down worn-out organelles.)

The protein actin is a component of a(n) __________.

microfilament ( Microfilaments are primarily composed of actin, a globular protein.)

Where is the genetic information of the cell stored?

nucelus (DNA is the genetic information of the cell, and it is stored in the nucleus.)

The genetic center of the eukaryotic cell is the __________.

nucleus ( The nucleus is the genetic center of the cell, and it contains the hereditary information.)

Chloroplasts are found in __________.

plant cells and some protists (Chloroplasts are lens-shaped organelles found in leaves and other green organs of plants and photosynthetic protists.)

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

plasma membrane ( The plasma membrane surrounds the cell and regulates the movement of materials into and out of the cell.)

Part complete Which of the following structure(s) is/are found in prokaryotic cells?

ribosomes ( Both prokaryotic and eukaryotic cells do have ribosomes)

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

secrete a lot of material (The Golgi apparatus intercepts ER vesicles, modifies the contents for export, and repackages the material in a Golgi vesicle that can fuse with the plasma membrane.)

Where are lipids made in the cell?

smooth endoplasmic reticulum (ER) (make lipids)

Which of the following is a function of the rough endoplasmic reticulum?

synthesizing receptor proteins ( These proteins are made by the rough endoplasmic reticulum and then processed by the Golgi apparatus before being inserted into the cell membrane.)

As cell size increases, the

volume increases proportionally more than the surface area

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 ( Prokaryotic cells lack any internal membranous compartmentalization whereas eukaryotic cells have membrane-bound organelles.)

To enter or leave any cell, substances must pass through _____.

the plasma membrane ( defines the boundary of the cell)

The function of the nucleolus is

to manufacture ribosomal RNA.

Your throat is dry, and you want the last cough drop in the box to last a long time in your mouth. What should you do?

Keep the cough drop whole. This maintains the smallest surface-to-volume ratio and slows the dissolution of the cough drop.

Which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell?

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 statements about the cytoskeleton is false?

Once laid down, the elements of the cytoskeleton are fixed and remain permanently in place.

Which of the following describes the function of the chloroplast?

The chloroplast converts light energy to chemical energy. ( The chloroplast makes food for the plant cell by converting light energy to chemical energy.)

Which of the following statements regarding the endomembrane system is false?

The endomembrane system is a system of interrelated membranes that are all physically connected.

What is the relationship between the Golgi apparatus and the plasma membrane?

The finished products of the Golgi apparatus may leave the cell through vesicles that fuse with the plasma membrane. (Transport vesicles from the Golgi move to the plasma membrane for export. In some cases the finished products become part of the plasma membrane or part of another organelle.)

The structural framework in a cell is the

cytoskeleton (The cytoskeleton is the structural framework in a cell ("cyto" refers to cell and "skeleton" refers to a structural framework).

Where would ribosomes be located that are responsible for producing enzymes which play a role in sugar metabolism?

cytosol ( The first steps of sugar metabolism occur within the cytosol. Therefore, the ribosomes in the cytosol are responsible for making the necessary enzymes.)

Which of the following is part of the endomembrane system?

golgi apparatus (The endomembrane system includes the ER, the Golgi apparatus, lysosomes, and vesicles. It manufactures, processes, and transports lipids and proteins. The Golgi apparatus processes and packages proteins.)

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

mRNA (The "m" in mRNA stands for "messenger"; mRNA is the messenger that carries genetic instructions from the nucleus to the cytoplasm.)

Mitochondria appear in the greatest numbers in cells that are _____.

metabolically active ( Mitochondria are the sites of cellular respiration, the catabolic process that generates ATP by extracting energy from food molecules, with the help of oxygen.)

Which of the following cytoplasmic structures functions in the transport of vesicles from the endoplasmic reticulum to the Golgi apparatus?

microtubules ( Vesicles travel along microtubules as they move from one part of the cell to another.)

The internal skeleton of a cell is composed of _____.

microtubules, intermediate filaments, and microfilaments ( these three types of fiber make up the cytoskeleton )

Where in a cell is ATP made?

mitochondria ( ATP is made in mitochondria.)

Much of the intracellular structure of a eukaryote cell is involved in protein synthesis. The accompanying figure shows the amounts of protein in cells at different parts of the cell cycle between two cell divisions. G1 is a stage just after the cell has divided, and G2 is the stage just before the cell divides again. S is a stage when the cell is synthesizing material such as DNA, mitochondria, and other organelles. The protein measured in the cells was likely synthesized by

ribosomes

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

ribosomes (Ribosomes dock on the rough ER, and proteins are completed inside the rough ER.)

The skin is the body's largest organ. It's made up of many different types of cells. Oils, produced by the sebaceous glands, prevent the skin from drying and splitting. The pigment melanin, produced by melanocytes in the epidermis, protects the skin from the harmful effects of ultraviolet radiation. Sweat, released through ducts to the skin surface, helps to cool the body. The types of cells that produce these compounds have different numbers of specific organelles, depending on their function. Melanocytes use many enzymes to produce melanin. Based on their function, you would expect melanocytes in the skin to have a higher than usual number of

ribosomes.

The Golgi apparatus

stores, modifies, and packages proteins.

The plasma membrane would fit into which general function category?

support, movement, and communication ( The plasma membrane is an important structure for cell communication with the external environment.)

Membrane proteins are synthesized by ribosomes that are attached to __________.

the endoplasmic reticulum (Ribosomes bound to endoplasmic reticulum generally make proteins destined either for inclusion into membranes; for packaging within certain organelles, such as lysosomes; or for export from the cell. The ribosomes attached to its surface are what give the RER its "rough" appearance.)

Which part of the mitochondrion shown enhances its ability to produce ATP by increasing the surface area of a mitochondrial membrane?

structure D