A & P Ch.4 Biology of the Cell - Study Guide

Cells similar in structure and function are arranged into structural units called _.

tissues

The process by which a DNA gene is copied into RNA is called _ .

transcription

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

translation

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

translation

The process that occurs on ribosomes by which a mRNA transcript is read and a new protein produced is called _____.

translation

Microtubules are composed of a protein called _ .

tubulin

Most human body cells have _ chromosomes in their nucleus.

46

Rapid digestion of a cell by its own lysosomes is called _ .

autolysis

Lysosomes remove old organelles through a process called _ .

autophagy

The centrosome contains two _ that lie perpendicular to one another.

centrioles

DNA and its associated proteins make up the substance

chromatin

A _ contains a single, long, tightly coiled molecule of DNA and is found in a dividing cell.

chromosome

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

concentration gradient or molecular size

Gap junctions are bridged by proteins called?

connexons

Which of the following are common cell shapes?

cube-like, spherical, column-like

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

cytokinesis

The study of cells is called:

cytology

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

cytoplasm

The three components of the cytoplasm of a cell are _, _, and _ .

cytosol, inclusions, organelles

Some membrane proteins catalyze (speed up) the rate of metabolic reactions. Those proteins are acting as _ .

enzymes

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

exocytosis; endocytosis

Forms of passive transport across cell membranes are _ .

facilitated diffusion, osmosis, and diffusion

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

glycocalyx

The plasma membrane is made up of three types of lipids: _, _, and _ .

glycolipids, phospholipids, cholesterol

In active transport processes, materials often flow from a region of _ concentration of the material to a region of _ concentration of the same material.

high; low

The extracellular fluid found outside and between cells is called _ .

interstitial fluid

There are two main types of active transport. These two types are: _ and _ .

ion pumps; bulk transport

Metaphase of mitosis is occurring when the chromosomes _ .

line up along the equatorial plate.

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

lysosomes

The two types of organelles found in cells are _ and _ bound.

membrane; non-membrane

The cytoskeleton has three 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

The organelle that has a double membrane, its own small piece of DNA, and synthesizes ATP is the _ .

mitochondrion

In the cell cycle, division of the nucleus is called _ .

mitosis

The nuclear envelope is made up of two membranes and has holes in it called _ _ . Similar to the plasma membrane, each layer of the nuclear envelope is made up of a _ bilayer.

nuclear pores; phospholipid

The parts of the subunits of ribosomes are assembled in the _ while the subunits are assembled into ribosomes in the _ .

nucleolus / cytosol

DNA wrapped around histones forms a complex known as a _ .

nucleosome

The _ is the cell's control center.

nucleus

The organelle in which transcription takes place is the _ .

nucleus

When water moves across a semi-permeable membrane, the pressure it exerts is _ pressure.

osmotic

The _ membrane is also called the cell membrane.

plasma

All materials that enter or leave the cell must pass across the __ __.

plasma membrane

The cell structure that functions as a 'gatekeeper' to regulate the passage of gases, nutrients, and wastes between the internal and external environments is the _ .

plasma membrane

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

plasma membrane structure

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

proteasomes

Chromatin is composed of _ and _ .

proteins; DNA

Match each type of RNA with it's description: rRNa tRNA mRNA

rRNa - structural component of ribosomes tRNA - match amino acids with codons in translation mRNA - synthesized in transcription, read in translation.

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

receiving

The primary cellular sites for the production of proteins are the _ .

ribosomes

Cell membranes can regulate the transport of materials into and out of the cell. Thus, cell membranes are said to be _ .

semi permeable

Which statements characterize smooth ER?

- It stores lipids. - It does not have ribosomes attached to it. - It is continuous with rough ER.

Which are required for translation?

- Amino acids - Ribosomes - mRNA - tRNA

Match the event of mitosis with each phase.

- Anaphase - centromeres that hold sister chromatid pairs separate - Prophase - nucleolus disappears - Metaphase - microtubules from mitotic spindle attach to centromeres - Telophase - chromosomes arrive at poles

Which statement(s) describe the G1 phase?

- Cells produce new organelles during this phase. - Near the end of this phase, centrioles begin to replicate. - Cells carry out specific metabolic activities during this phase. - Cells grow during this phase.

Which statement(s) characterize metaphase?

- Chromosomes line up along the equatorial plate of the cell. - It directly follows prophase.

Which statement(s) characterize the S phase of interphase?

- DNA replicates during this phase. - It directly follows the G1 phase.

Which statements characterize organelles?

- Each type of organelle has a specific function. - They are located within cells. - They play roles in growth, repair, and cellular maintenance.

Examples of how cells communicate through direct contact:

- Fertilization on an ovum (egg) by a sperm. - The immune system differentiates healthy body cells and foreign cells. - Regrowth of cells following an injury.

Match the tonicity to its definition.

- Isotonic - The cytosol and solution outside the cell have the same concentration of solutes. - Hypotonic - The solution outside the cell has a lower concentration of solutes than the cytosol. - Hypertonic - The solution outside the cell has a higher concentration of solutes than the cytosol.

True statements regarding the cell membrane:

- It consists of a phospholipid bilayer. - It can merge with intracellular membranous vesicles. - It is a selectively permeable membrane. - It isolates the cytoplasm from the surrounding environment.

Which statements correctly describe the nuclear envelope?

- It controls the entry of substances into and out of the nucleus. - It is a double membrane. - It contains phospholipids - It is continuous with the ER.

Which statement(s) characterize telophase?

- It directly follows anaphase. - It is the last phase of mitosis. - It overlaps with cytokinesis.

Which statement(s) describe the G2 phase of interphase?

- It is a growth phase. - Organelle production occurs during this phase. - It directly follows the S phase of interphase.

Which statements correctly characterize cytosol?

- It is also called intraceullar fluid. - It has a high water content. - It contains proteins and carbohydrates. - It contains many dissolved solutes.

Match the membrane-bound organelle with its structure.

- Lysosomes - Membrane sacs with digestive enzymes - Smooth ER - Interconnected network of membrane tubules and vesicles; no ribosomes attached - Golgi apparatus - Stacked series of flattened, smooth membrane sacs with associated transport vesicles - Rough ER - Flattened intracellular network of membrane sacs called cisternae; ribosomes attached on cytoplasmic surface

Match the non-membrane bound organelles with their function.

- Microfilaments - aid is muscle contraction and intracellular movement - ribosomes - synthesize proteins - intermediate filaments - stabilize cell junctions - cytoskeleton - provides structural support within cells

Which statements are true regarding proteins?

- Proteins make up about half of the plasma membrane by weight. - Proteins can 'float' and move about the fluid bilayer.

Which statement(s) characterize anaphase?

- Spindle fibers pull sister chromatids apart. - It directly follows metaphase.

Which are functions of rough ER?

- Storage of proteins to be exported from the cell. - Transporting enzymes that are to be stored in lysosomes. - Production of proteins.

Match the name of each phase of mitosis with its description.

- Telophase - chromosomes arrive at poles - Prophase - nuclear envelope disappears - Metaphase - chromosomes line up on the equatorial plate - Anaphase - centromeres split and chromosomes move toward opposite poles

Which statement(s) characterize prophase?

- The nuclear envelope disappears - It is the first stage of mitosis. - Chromatin condenses into chromosomes.

Which of the following statements correctly describe enzymes?

- They are catalysts. - They are important for metabolic activites of a cell. - They are proteins.

Which statements characterize microvilli?

- They are microscopic projections of the plasma membrane. - They are smaller than cilia. - They function to increase the surface area of the plasma membrane.

Which statements describe chromosomes?

- They are more condensed than chromatin. - They contain DNA and proteins.

Which statements are true regarding peripheral proteins?

- They can "float" and move about the phospholipid bilayer. - They are attached loosely at the cell membrane. - They may serve as enzymes.

Which of the following statements are true regarding integral proteins?

- They can act as receptors. - They can act as membrane channels. - They are embedded within the phospholipid bilayer.

Match each membrane protein type with its function.

- Transport - channels, carriers, and pumps - identity markers - tell the immune system they belong to the body - enzymes - catalysts - cell-adhesion proteins - attachment to other cells - cell surface receptor - ligands

Match the DNA structures.

- Uncoiled chromatin - genes within the DNA direct the production of cellular proteins - Chromosomes - becomes visible only when the cell is dividing - Nucleosome - DNA double helix wound around a cluster of histones - Chromatin - finely flamented mass of DNA and protein

A codon can code for all of the following:

- a stop signal where the reading of the mRNA ends - the start of protein synthesis - an amino acid

Types of transport proteins include:

- carriers - pumps - channels

Which of the following are found in the cell membrane?

- cholesterol - phospholipids - transport proteins

Match the components of cells with their function.

- cytoplasm - Place of many metabolic processes of the cell - nucleus - acts as cell control center - organelles - carry out specific metabolic activities of the cell - cytosol - provides support for organelles, serves as medium through which intracellular diffusion occurs. - nucleolus - synthesizes rRNA and assembles ribosomes in the nucleus

Match the components of cells with their functino.

- cytoplasm - place of many metabolic processes of the cell - nucleus - acts as cell control center - organelles - carry out specific metabolic activities of the cell - nucleolus - synthesizes rRNA and assembles ribosomes in the nucleus - cytosol - provides support for organelles; serves as medium through which intracellular diffusion occurs

Peroxisomes break down harmful substances including:

- fatty acid molecules - alcohol - hydrogen peroxide

Match the components of cells with their structure.

- flagella - long, singular membrane extension containing microtubules - microvilli - numerous thin membrane folds projecting from the free cell surface - cilia - short, membrane-attached projections containing microtubules, occur in large numbers on exposed membrane surfaces - centrioles - paired perpendicular cylindrical bodies; composed of microtubule triplets

Match the components of cells with their structure.

- inclusions - droplets of melanin, protein, glycogen granules, or lipid - centrosome - amorphous region adjacent to nucleus; contains a pair of centrioles - centrioles - paired perpendicular cylindrical bodies; composed of microtubule triplets - cytoskeleton - organized network of protein filaments or hollow tubules throughout the cell

Match the components of cells with their structure.

- inclusions - droplets of melanin, protein, glycogen granules, or lipid - cytoplasm - contains cytosol, a viscous fluid, and inclusions and organelles - organelles - membrane-bound and non-membrane-bound structures that have unique functions and activities - smooth ER - interconnected network of membrane tubules and vesicles; no ribosomes attached

Sister chromatids are:

- joined together by a centromere. - for the most part genetically identical.

Match the components of cells with their structure.

- mitochondria - double membrane structures with cristae - rough ER - flattened intracellular network of membrane sacs called cisternae; ribosomes attached on cytoplasmic surface - lysosomes - membrane sacs with digestive enzymes - golgi apparatus - stacked series of flattened, smooth membrane sacs with associated transport vesicles

Select all of the following that are required for transcription.

- ribonucleotides - DNA - RNA polymerase

Which of the following forms of RNA are required in translation?

- ribosomal - transfer - messenger

Place the steps of transcription in order:

1. DNA is unwound and RNA polymerase attaches to the promoter of the gene. 2. RNA polymerase forms an RNA copy of the gene. 3. The RNA strand is released from the DNA strand.

Place the following steps in correct order to describe how materials move through the Golgi apparatus.

1. New proteins in the rough ER are put into a transport vesicle. 2. Transport vesicle fuses with the Golgi apparatus. 3. Proteins are modified as they move through Golgi apparatus. 4. Modified proteins are packaged into secretory vesicles.

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 methionine. 3. Anticodons and codons are paired; amino acids are joined. 4. A stop codon is read. 5. Ribosomal subunits separate releasing the protein.

The steps of exocytosis:

1. Vesicle nears plasma membrane. 2. Fusion of vesicle membrane with plasma membrane. 3. Plasma membrane opens to outside cell. 4. Release of vesicle components to interstitial fluid.

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

Which of the following is required for osmosis to occur?

A selectively permeable membrane

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

Channel-mediated

Match the non-membrane-bound organelles with their function.

Cilia - move fluid, mucus, and materials over the cell surface Microvilli - increase membrane surface area for increased absorption and/or secretion Flagellum - propels sperm cells in human male Microtubules - move chromosomes during cell division

_ is the tendency of molecules to move down their concentration gradient.

Diffusion

True or False: In transcription a DNA gene is read and copied to produce a newly formed strand of DNA.

False

True or False: Loosely coiled DNA is referred to as a chromosome.

False

True or False: The steeper the concentration gradient, the lower the osmotic pressure.

False

True or False: DNA is considered the "boss of the cell" because it directs the synthesis of carbohydrates that carry out body functions.

False. DNA is considered the cell's control center because it directs the synthesis of proteins that carry out body functions.

_ 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

Cell A is in which phrase?

Interphase

What are the two phases of the cell cycle?

Interphase and the mitotic phase

_ are thin, microscopic projections extending from the surface of the plasma membrane. They are smaller than cilia.

Microvilli

Which organelles are the 'powerhouses' of the cell because they perform aerobic respiration?

Mitochondria

_ is the cell division that takes place in somatic cells.

Mitosis.

Sodium ions enter the cell through _____ _____channels as they move _____ their concentration gradient.

Na+ leak down

Which of the following is correct about transcription?

RNA polymerase builds an RNA copy of a DNA gene

This is NOT one of the major passive transport processes.

Receptor mediated endocytosis

Stages of mitosis in the proper sequence:

Prophase, metaphase, anaphase, and telophase

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

Proteasomes

_ are complex, diverse molecules composed of chains of amino acids.

Proteins

The synthesis of steroid hormones occurs in the _ .

smooth ER.

The microscope of choice for a detailed three-dimensional study of the surface of a cell specimen is the:

Scanning electron microscope

Which type of microscope scans an electron beam over the surface of a specimen?

Scanning electron microscope

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

Simple

_ cells include all of the cells in the body except sex cells.

Somatic

The process by which cells commit suicide is called _ .

apoptosis

True or False: A transmission electron microscope (TEM) uses an electron beam to create an image for viewing.

True

True or False: Cilia and flagella are projections that extend from the surface of some cells.

True

True or False: Osmosis is a passive form of transport across the cell membrane.

True

Intestinal cells are joined by what type of membrane junction in order to prevent digestive juices from moving between and damaging adjacent cells?

Tight junctions

Which of the following is a general function performed by all cells?

To obtain nutrients

What is the synthesis of a new protein from an mRNA transcript called?

Translation

True or False. Ion pumps are important in creating and maintaining steep concentration gradients of sodium ions and potassium ions between the internal and external environments of some human cells.

True

True or False. Some human cells are large enough to be seen with the naked eye.

True

When viewed under a transmission electron microscope, the Golgi apparatus looks like _ .

a stack of pancakes