A&P Chap 4

Put the steps of translation into the proper order.

1. Ribosomal subunits bind the mRNA and a tRNA 2. Protein synthesis begins with the amino acid methoinine 3. Anticodons and codons are paired; amino acids are joined 4. A stop codon is read 5. Ribosomal subunits separate releasing the protein

The sodium-potassium exchange pump transports ________ (number) sodium ions out of the cell for every _________ (number) potassium ions it transports into the cell.

3, 2

Primary active transport uses phosphate from the breakdown of _________ to phosphorylate the membrane transport pump resulting in the change in a _____________ conformation (shape) and the subsequent movement of a solute across a membrane.

ATP, protein's

Exocytosis is a means by which cells release substances to the outside. This process requires the cell to expend energy in the form of _____________. Typically the secretion is packaged into __________ which fuse with the __________ membrane prior to release.

ATP, vesicles, plasma

Match DNA structures:

Chromatin: finely filamented mass of DNA and proteins Chromosomes: become visible only when the cell is dividing Nucleosome: DNA double helix wound around a cluster of histones

Match the function of the plasma membrane with its mechanism of action.

Communication: contains receptors that recognize and respond to molecular signals Intercellular connection: junctions form between neighboring cells Physical barrier: phospholipid bilayer separates substances inside and outside the cell Selective permeability: regulates entry and exit of ions, nutrients, and waste molecules through the membrane

All cells are able to undergo cell division and make more cells of all types.

False

The steeper the concentration gradient of a solute, the lower the osmotic pressure.

False

________ junctions allow small solutes to travel between adjacent cells.

Gap

The primary structure for the processing and packaging of proteins for transport out of the cell is the _________.

Golgi apparatus

Match the stage of translation with the events that occur within it.

Initiation: mRNA binds to ribosomal subunits and a tRNA carrying methioline Elongation: amino acids are added to form a protein Termination: ribosome subunits separate and the protein is released

Match the components of the nucleus with their structure and function.

Nuclear envelope: double membrane boundary between cytoplasm and nuclear contents Nuclear pores: openings through the nuclear envelope Nucleolus: synthesizes rRNA and assembles ribosomes in the nucleus Chromosome: filamentous association of DNA and histone proteins

___________ detoxifies harmful substance produced by the cell or taken into the cell.

Peroxisomes

__________ are protein-digesting organelles in the nucleus and cytosol of cells.

Proteasomes

Select all of the following that are required for the transcription.

RNA polymerase, ribonucleotides, DNA

Which os the following is not a type of cell membrane junction?

Synapse

Peroxisomes are usually smaller in diameter than lysosomes.

True

A transmission electron microscopes (TEM) produces what kind of image?

Two-dimensional

Microfilaments are made up of trow strands of the protein ______________.

actin

A codon can code for all of the following except:

an anticodon of mRNA

The process by which cells commit suicide is called ____________.

apoptosis

Rapid digestion of a cell by its own lysosomes if called ________.

autolysis

The centrosome contains 2 _____________ that lie perpendicular to one another.

centrioles

Ion movement through small proteins in the membrane is an example of what type of diffusion?

channel-mediated

Types of transport proteins include:

channels, carriers, pumps

K+ movement out of the cell is facilitated by its ____________ ____________ gradient but opposed by the ______________ gradient.

chemical composition, electrical

A type of lipid called _____________ is scattered within the hydrophobic regions of the phospholipid bilayer, where it strengthens the membrane and stabilizes it at extreme temperatures.

cholesterol

Which of the following functions to strengthen the plasma membrane and stabilize it at extreme temperatures?

cholesterol

A 3 nucleotide unit of mRNA is known as a __________.

codon

In the cell cycle, division of the cytoplasm is called __________.

cytokinesis

The study of cells if called ________.

cytology

The _________ is the general term for all cellular contents between the plasma membrane and the nucleus.

cytoplasm

A difference in solute concentration can exist between the ___________ and the interstitial fluid because solutes are prevented from moving across the plasma membrane.

cytosol

The watery, syrup-like fluid of the cytoplasm is called ___________.

cytosol

__________ is the viscous fluid of the cytoplasm.

cytosol

The 3 components of the cytoplasm of a cell are ____________, _______________, and _____________.

cytosol, inclusions, and organelles

The 3 components of the cytoplasm of a cell are _______________, _____________, and __________.

cytosol, inclusions, organelles

Cells induced to undergo apoptosis exhibit all of the following signs:

destruction of organelles, abnormal development in plasma membrane structure, DNA degradation, condensation of the cytosol

The ______________ gradient is dependent on the combination of the ______________ gradient and the chemical concentration gradient.

electrochemical, electrical

Which of the following is NOT correct regarding simple diffusion?

energy (ATP) for the action is provided by the plasma membrane

Bulk transport refers to the movement of macromolecules across a selectively permeable membrane. There are 2 categories of bulk transport mechanisms, _____________ and ____________.

exocytosis, endocytosis

Which of the following moves across the plasma membrane easiest?

fatty acids

Exocytosis if the process whereby large molecules are secreted _________ the cell.

from

Ligands are molecules released from one cell that bind to the receptor of another cell. Which of the following are types of receptors that can bind ligands?

g protein-coupled, enzymatic, channel-linked

Body cells communicate to other immune cells that they both belong to the body and are healthy through direct contact that involves which part of the cell?

glycocalyx

The 'coating of sugar' on the cell's surface is called the _________.

glycocalyx

Proteins with attached carbohydrate groups are ____________.

glycoproteins

Peroxisomes break down harmful substances including:

hydrogen peroxide, fatty acid molecules

Which of the following are classified as plasma membrane proteins?

identity markers, receptor, enzymes, transport proteins

Desmosome membrane junctions are reinforced by what type of protein filament?

intermediate filaments

What are the 2 phases of the cell cycle?

interphase and the mitotic phase

After transcription, RNA undergoes splicing in which the ________ are removed and the _________ are spliced together.

introns, exons

Active transport mechanisms that move ions across a selectively permeable membrane are referred to as _____ pumps. Those that move one type of ion into the cell and another type out of the cells are specifically called _________ pumps.

ion, exchange

In facilitated diffusion, __________ and _____________ diffuse across a selectively permeable membrane down their concentration gradient.

ions, small polar molecules

What statements characterize smooth ER?

it can detoxify drugs, it stores lipids, it does not have ribosomes attached to it

Which statements correctly describes the nuclear envelope?

it contains phospholipids, it is continuous with the ER, it is a double membrane, it controls the entry of substances into and out of the nucleus

Which statements correctly characterize cytosol?

it contains proteins and carbohydrates, it has a high water content, it is also called intracellular fluid, it contains many dissolved solutes

Which of the following is NOT true regarding the cell membrane?

it is primarily made of cytosol

Which statements characterize prophase?

it is the first stage of mitosis, the nuclear envelope disappears, chromatin condenses into chromosomes

Which statements characterize telophase?

it is the last phase of mitosis, its processes are the reverse of prophase, it directly follows anaphase

Which statements are true regarding cholesterol?

it strengthens the plasma membrane, it is scattered within the hydrophobic regions of the phospholipid bilayer

Sister chromatids are:

joined together by a centromere, separated by spindle fibers during anaphase

Light microscopy passes _______ through the structures within a cell whereas electron microscopy uses a _____________ of ___________ to "illuminate" the specimen.

light, beam, electrons

Old or worn out organelles in a cell are removed by what organelle?

lysosomes

Which of the following are considered to be membrane-bound organelles.

lysosomes, peroxisomes, golgi apparatus, mitochondria, rough/smooth ER

Which of the following are classified as part of the endomembrane system?

lysosomes, peroxisomes, rough/smooth ER, golgi apparatus

Which of the following describe the general functions of cell.

maintain shape of the cell, dispose of wastes, obtain nutrients

The cytoplasm has 3 separate protein filament components; they are _______ filaments, _______________ filaments, and microtubules.

micro, intermediate

Internally, cilia and flagella contain cytoplasm and _______________. They are enclosed by the plasma membrane.

microtubules

One of the main factors that influences membrane permeability is __________.

molecular size

A resting membrane potential is essential in the normal function of ________ cells.

nerve, muscle

DNA wrapped around histones forms a complex knowns as a _____________.

nucleosome

The building blocks that form the double helical molecule called DNA are ____________.

nucleotides

The building blocks that form the double helical molecule called DNA are _____________.

nucleotides

The 3 components of most human body cells are a plasma membrane, cytoplasm, and _____________.

nucleus

The ________ is the cell's control center.

nucleus

The organelle in which transcription takes place is the ____________.

nucleus

During cell division, the centrosome functions to:

organize the microtubules that help move the chromosomes

The net diffusion of water across a selectively permeable membrane that is freely permeable to water but not to solute is called ____________.

osmosis

The cytosol close to the plasma contains relatively more __________ potassium than does the interstitial fluid that is close to the plasma membrane.

potassium

__________ diffusion is the most important factor in establishing the specific value of the resting membrane potential.

potassium

The 'garbage disposals' for unwanted and/or excess protein in a cell are the ___________.

proteasomes

Non-membrane bound organelles are composed of which of the following?

protein, RNA

Cells induced to undergo apoptosis exhibit all of the following signs except:

rapid replication of it's genetic material

The cis-face of the Golgi apparatus is also called the ___________ region.

receiving

Which of the following are NON membrane-bound organelles?

ribosomes, centrosomes, the cytoskeleton, proteasomes

__________ diffusion occurs when substances move across cell membranes unaided because they are either small, nonpolar, or both.

simple

Sodium diffusion into cells occurs _________ to the loss of K+.

simultaneously

Where might you find tight junctions in the body?

small intestine, urinary bladder

The synthesis of steroid hormones occurs in the _________.

smooth ER

Match the membrane-bound organelles with their structure.

smooth ER: interconnected network of membrane tubules and vesicles; no ribosomes attached rough ER: flattened intracellular network of membrane sacs called cisternae; ribosomes attached on cytoplasmic surface golgi apparatus: stacked series of flattened, smooth membrane sacs with associated transport vesicles mitochondria: double membrane structures with cristae

Which of the following is NOT an example of how cells communicate through direct contact?

the cells of hypothalamus send out pyrogens to induce fever

Which of the following statements are true regarding integral proteins?

they act as identity markers for the cell, they can act as membrane channels, they can act as receptors

Which statements are true regarding peripheral proteins?

they are attached loosely to the cell membrane, they may serve as enzymes, they cal "float" and move about the phospholipid bilayer

Which of the following statements correctly describe enzymes?

they are proteins, they are catalysts, they may be attached to the internal or the external surface of a cell

Which statements are true regarding glycolipids?

they are unique to each individual except identical twins, they are located only on the outer later of the plasma membrane

Which of the following statements are true regarding integral protein?

they can act as receptors, they can act as membrane channels, they act as identity markers for the cell

____________ junctions are found between adjacent epithelial cells and prevent substances from leaking between them

tight

The process in which mRNA copy of a gene is read by ribosomes in the cytoplasm to produce a protein is called __________.

translation

Microtubules are composed of a protein called _____________.

tubulin

Both Na+ and K+ are pumped by the Na+/K+ pumps ________ their concentration gradients in maintaining the resting membrane potential.

up

When a solute concentration exists, a _________ also exists.

water concentration

Flagellum means _______.

whip-like