BIO EXAM 2 QUESTIONS/ANSWERS

In attempt to visualize the fluid mosaic model of a membrane, we could describe the ______ as floating in a sea ________.

Proteins; lipids

Which statement best describes the relationship between the RNA and DNA?

RNA is a copy of DNA that makes his own proteins

What is a role of proteins found in a eukaryotic plasma membranes:

Regulating the flow of a material through the membrane

What activity occurs in the nucleolus?

Ribosome parts are created

A cell without nucleoli is probably not producing

Ribosomes

The cell organelle that organizes protein synthesis is

Ribosomes

The secondary cell wall in plants add:

Rigidity to the cell

If a cell membrane is pierced with a very fined needle, the cell will subsequently ______.

Seal itself

Golgi bodies appear to function in:

Secretion of cell products

Not all substances can cross the cell membrane, for this reason, the cell membrane is said to be

Selectively permeable

In eukaryotic cells, the endoplasmic reticulum can

Serve as the internal transportation system of a cell

What are cilia?

Short, eyelash-like projections from the cell membrane that provide for locomotion

Organelles involved in the synthesis of steroids and other lipids in gland cells are

Smooth ER

Which of the following involved in lipid synthesis and modification?

Smooth ER

If a plant synthesizes a secondary wall, it is laid down:

Between the plasma membrane and the primary cell wall

The process where water is removed between two amino acids to build a dipeptide is called a:

Dehydration synthesis

Four of the five items listed below are cytoplasmic organelles. Select the exception

Nucleolus

The cell organelle or structure that stores in DNA and synthesizes RNA is the

Nucleus

The subunits for ribosomes are synthesized in the

Nucleus

A peptide bond forms

-By the removal of a water molecule -By a dehydration reaction -Between two amino acids

What role(s) does the cytoskeleton play in a living cell? (Hint: Check only one answer)

-Maintaining cell shape -Movement -Contraction -Internal cell support

________ can readily diffuse across a lipid bilayer.

-Oxygen -Carbon Dioxide

This organelle is more likely to be found in an plant cell than in a animal cell

Central vacuole

Ezymes are

-Very specific -Are organic molecules -Act as catalysts -Have special shapes that control their activities

A prokaryote has

A cell membrane

For diffusion to occur in a given direction, there must be

A gradient

The fluid-mosaic model represents the modern view of

A membranes structure

What is similar about exporting proteins for a cell and digesting food particles within a cell?

Both processes involve the formation of vesicles

The cell wall of plants consist largely of

Carbohydrates

Plants need which of the following to carry on photosynthesis?

Carbon dioxide and water

A cytologist would principally investigate:

Cell and cell organelles

The outer limit of a living cell is always the:

Cell membrane

The part of the cell that regulates movement of substances into and out of the cell is the

Cell membrane

Provides structure and support outside the plant cells

Cell wall

We usually compare all eukaryotic cells as a group to all prokaryotic cells. However, some types of eukaryotic cells have characteristics that are found in prokaryotic cells, but not found in other eukaryotic cells. What feature do plant cells share with prokaryotic cells, but not animal cells?

Cell wall

The fluid filled sac that may store food, acids, vitamins, ions or water in plant cells and is involved in fluid

Central vacuole

Plant cells generally lack:

Centrioles

What organelle in higher plant cells contain chlorophyll?

Chloroplasts

Which organelle releases oxygen?

Chloroplasts

Inside the nuclear envelope the DNA maybe found in the form of fine diffuse strands is called

Chromatin

Four of the five structures listed below are composed of membranes. Select the exception. -Endoplasmic reticulum -Granum -Nuclear envelope -Plasma membrane -Chromosomes

Chromosome

Deoxyribonucleic acid (DNA) is believed to be the most important substance of:

Chromosomes

In all cells DNA is located in

Chromosomes

The "blueprints" or "computer tapes" in a cell that control all its activity are the

Chromosomes

What is the difference between cilia and flagella?

Cilia are much shorter than flagella

In general the net movement of molecules in a fluid is a response to the

Concentration gradient

Lysosomes

Contain digestive enzymes

The inner layer of the mitochondrial membrane may be invaginated (infolded) to form:

Cristae

Protein fibers in the cytoplasm maintain the three-dimensional structure of animal cells

Cytoskeleton

What is the exact function of DNA?

DNA provides the blueprints for making proteins

This illustration of which cell organelle?

Dictyosome

The organelle directly responsible for packaging and exporting cellular products is the:

Dictyosome (Golgi)

The cell organelle that processes and packages substances produced by the cell is?

Dictyosomes

The net movement of molecules from a high concentration to a low concentration is described by which of the following?

Diffusion

Nucleic acids confined to the nucleus or nucleoid indirectly

Direct protein synthesis out in the cytoplasm

The nucleic acid DNA can do only two things, one is to make RNA and other is to:

Duplicate itself

The primary structural difference between plant and animal cells is that most plant cells are:

Enclosed by a cell wall

What cellular process involves an inward sinking of a small patch of membrane to form a cytoplasmic vesicle?

Endocytosis

Which of the following are sometimes referred to as a rough or smooth depending on surface structure?

Endoplasmic reticula

The system of canals, tubes, and sacs that transport molecules inside the cytoplasm is the:

Endoplasmic reticulum

Which of these is not found in the nucleus?

Functioning ribosomes

Scientists demonstrated the fluidity of plasma membranes by

Fusing the membranes of two different species

Which animal cell junction correctly matched with its function? -Adhering; allows rapid flow of substance -Tight; holds cells together -Gap; connects cytoplasm of adjoining cells -Adhering; seals adjoining cells -Gap; prevents passage of materials

Gap; connects cytoplasm of adjoining cells

Which of the following organelles is correctly matched with its function? -Nucleus; protein synthesis -ER; heredity -Golgi bodies; packaging -Mitochondria; digestion -Chloroplasts; storage of lipids

Golgi bodies; packaging

Vesicles pinched off from the ER most likely are on their way to the

Golgi body

Chloroplasts contain disk-like membraneous sac arranged in stacks. The stacks are called

Grana

The term cell comes from this scientist's work and his description of the compartmentation he saw in thin slices of corks:

Hooke

In a lipid bilayer, ______ of lipid molecules are sandwiched between ________.

Hydrophobic tails; hydrophilic heads

As a result of its involvement in a reaction, an enzyme

Is unchanged

All cell membranes and organelle membranes consist of two phospholipid layers called a:

Lipid bilayer

Two _____ act as a barrier between the inside and the outside of the cell

Lipid bilayers

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

Lipid manufacture

What are the flagella?

Long whip-like projections

Which of the following is a type of vesicle produced by the Golgi body?

Lysosome

The cell organelle that digests molecules, old organelles and foreigns substance inside cells is

Lysosomes

Which of the following contain enzymes, are the main organelles of intracellular digestion, and can digest whole cells?

Lysosomes

The largest cytoskeletal element is the:

Microtubule

Which of the components of cytoskeleton are used directly for movement?

Microtubules

Cells with high energy requirements, such as muscle (as in a humming bird), tend to have many

Mitochondria

Which of the following are the primary cellular sites for the release or capture of energy from carbohydrates?

Mitochondria

Which of the following organelles is most important in providing energy to the cells?

Mitochondrion

Which organelle below is capable of production its own protein?

Mitochondrium

This organelle is more likely to be found in an animal cell than in a plant cell: -Mitochondrion -Central vacuole -Cell membrane -Nucleus

None of the above

The RNA in the nucleus leaves through

Nuclear pores

The presence of which of the following features distinguishes prokaryotic cells from eukaryotic cells?

Nucleoid

Which structures are found in a prokaryotic cell?

Nucleoid, ribosomes, chloroplast, cell wall

Which of the following is a characteristic of DNA?

Occurs in all cells

A white blood cell is engulfing a bacterium is an example of ______.

Phagocytosis

Membranes are composed mainly of:

Phospholipids and proteins

Which structure(s) would be found in eukaryotic cells but NOT in prokaryotic cells?

Plastids and nuclear membrane

What is the smallest thing in the following list: -Mitochondrion -Prokaryote -Atom -Virus -Frog embryo

Prokaryote

Which of the following is a function of the Golgi apparatus?

Protein modification

Most membrane functions are carried out by ________.

Proteins

There are many kinds of ________ in cell membranes; they help to move material into and out of the cell

Proteins

What is the main product of the rough endoplasmic reticulum?

Proteins

What is the purpose of the cell wall?

Support and protection

If lysosomes bursts inside a cell, the immediate result is likely to be:

The cell will be digested within

Cilia and flagella are most similar in:

Their internal composition and structure

In a typical cell the substance found in the highest percentage is:

Water

In reference to diffusion, "passive" really means:

no ATP energy is required