Biology 168

what is the function of chloroplast

- cover light energy to chemical energy - perform photosynthesis

how are materials delivered to lysosomes?

- phagocytosis -autophagy - receptor:mediated endocytosis(the process of the cell membrane can pinch off a vesicle/to bring outside material into the cell/ a third type of endocytosis is pinocytosis; it brings fluid into the cell)

give a list of tasks performed by bacterial organelles

- storing calcium ions or other key molecules - holding crystals of the mineral magnetite

list several things about the nucleus structure

- surrounded by a double membrane nuclear envelope - the nuclear envelope is studded with pore-like openings - the inside surface is linked to fibrous proteins - the nucleus has a distinct region called the nucleolus

Mitochondria have two membranes. Describe both

- the inner one is folded into a series of sac-like cristae -the solution inside the cristae is the mitochondrial core function

list some things about the structure of ribosomes

- they are non-membranous thus are not considered organelles - they have large and a small subunit - both contain RNA molecules - can both be attached to the rough ER - can be free in the cytosol, the fluid part of the cytoplasm

when are proteins packaged into vesicles?

- when they move from the RER to the golgi apparatus - when the golgi apparatus to the cell surface

describe the cytoskeleton structure

-composed of protein fibers -gives the cell shape and structural stability

what does the secretary pathway propose?

-proteins intended for secretion from the cell are synthesized - they are processed in a highly prescribed set of steps

list some facts about eukaryotes

-range in size from very small to very large (microscpic algae to 100-meter tall redwood trees) -many are multicellular (occasional unicellular) - most eukaryotic cells are larger than most prokaryotic cells

describe the mitochondria

-they have their own DNA - they manufacture their own ribosomes

Name three domains and tell whether they are prokaryotic or eukaryotic

1. Bacteria: pro 2. Archaea: neither 3. Eukarya: euk

Name and describe four things all cells have

1. Nucleic Acids: store and transmit information 2. Proteins: performs most of cells functions 3. Carbs: chemical energy, carbon, support, identity 4. Plasma Membrane: selectively permeable membrane barrier

Name and Describe the two groupings of life

1. Prokaryotes: lack a membrane-bound nucleus 2. Eukaryote: have a nucleus

there are four key differences between eukaryotic and prokaryotic cells and they have been identified as what?

1. eukaryotic chromosomes are found inside a membrane-bound compartment termed nucleus 2. eukaryotic cells are often much larger 3. eukaryotic cells contain extensive amounts of internal membrane 4. eukaryotic cells feature a diverse and dynamic cytoskeleton

Give some structural similarities of bacteria

1. plasma membrane 2. a single chromosome 3. ribosomes; which synthesize proteins 4. stiff cell wall

the compartmentalization of eukaryotic cells offers two primary advantages, what are they?

1. separation of incompatible chemical reactions 2. increasing the efficiency of chemical reactions

what is the function of the mitochondria?

ATP production is a mitochondrion's core function

Which of the following statements is true? D.) Larger cells have less volume than smaller cells. A.) As cells get larger, the volume increases more than the surface area. B.) Larger cells have less surface area than smaller cells. C.) As cells get larger, the surface area increases more than the volume.

As cells get larger, the volume increases more than the surface area.

Using concepts from Chapter 3, which statement best explains why proteins—and not RNA, DNA, carbohydrates, or lipids—are the molecules responsible for "reading" the array of molecular zip codes in cells?

Because proteins can have diverse structures and chemical properties, different proteins can "read" different zip codes by interacting specifically with them.

T or F. Cell components and structures do not correlate with their functions.

False. they do correlate with their function

Which answer most accurately summarizes the (1) structural and (2) functional properties of actin filaments, intermediate filaments, or microtubules?

Intermediate filaments: (1) many subunit types; (2) one cellular role

How are proteins transported to their correct location in the cell?

Proteins contain molecular "zip codes" that allow them to be shipped to the correct cellular compartment.

For prokaryotic cells, which statement is correct concerning how the structure of a particular cell component correlates with its function?

The cell wall is a tough, fibrous layer that protects the cell and gives it shape and rigidity.

T or F. Inside the membrane, all the contents of a cell excluding the nucleus (eukaryotes) are collectively termed the cytoplasm

True

what is the dynamic cytoskeleton?

a dense and complex network of fibers that helps maintain the cell shape by providing structural support

in the prokaryotic species the chromosome contains what?

a long strand of DNA and a few support proteins. The DNA double helix coils itself with the aid of enzymes to form a compact "supercoiled" structure.

define organelle && give two things that are contained inside an organelle

a membrane-bound compartment inside the cell 1. enzymes or structures specialized for a particular function 2. commonly found in eukaryotic cells

What three distinct elements make up the cytoskeleton in eukaryotic cells?

actin filaments, intermediate filaments, and microtubules

_______ and _______ cell walls are composed of a tough, fibrous layer that surrounds the plasma membrane

bacteria && archaeal

_____ is/are identical in structure to centrioles. A. Chromatin B. Nuclear envelopes C. Microfilaments D. Mitochondria E.Basal bodies

basal bodies

Which of the following cell structures is only found in algal and plant cells? A.) cell walls B.) a cytoskeleton C.) chloroplasts D.) Golgi apparatus

chloroplasts

The _____ is composed of DNA and protein. A. ribosome B. mitochondrion C. centriole D. chromatin E. flagellum

chromatin

ribosome

consists of RNA molecule and protein and are used for protein synthesis

how is cargo brought into the cell?

endocytosis: ("inside-cell-act") refers to - any pinching off of the plasma membrane -resulting in the uptake of material from outside the cell

some prokaryotes have a tail-like __________ on the cell surface that spin around to move the cell

flagella

give the function of of bacterial organelles

functions as a compass needle to help cells sense a magnetic field and swim in a directed way/organizing enzymes responsible for synthesizing complex carbon compounds from carbon dioxide

many species have an additional layer outside the cell wall and what is it composed of?

glycolipids

specialized peroxisomes in plants are called what?

glyoxysomes

in prokaryotic cells, where are the other structures contained?

in the cytoplasm

What does the ER signal sequence do?

it binds to a signal recognition particle (SRP) that then binds to a receptor in the ER membrane

what does the plasma membrane consist of?

it consists of a phospholipid bilayer and has proteins that either span the bilayer or attach to one side

what does the signal hypothesis predict?

it predicts proteins bound for the endomembrane system have a zip code which directs the growing polypeptide to the ER. This zip code is a 20 amino-acid-long ER signal sequence.

describe some peroxisome oxidation reactions

liver cell peroxisomes contain enzymes that remove electrons from, or oxidize, the ethanol in alcoholic beverages. Specialized peroxisomes in plants called, glyoxysomes are packed with enzymes and they oxidize fats to form a compound for energy storage

Which organelle plays a role in intracellular digestion? chloroplast A.) plasmodesma B.) Golgi apparatus C.) lysosome D.) ribosome

lysosome

The cilia and flagella of eukaryotic cells are composed of _____. A.) monofilaments B.) microtubules C.) pili D.) microfilaments E.) intermediate filaments

microtubules

Which of these are hollow rods that shape and support the cell? A. plasma membrane B. chloroplasts C. peroxisomes D.microtubules E. microfilaments

microtubules

Which of these organelles carries out cellular respiration? A. smooth endoplasmic reticulum B. mitochondrion C. nucleolus D. chromatin E. ribosomes

mitochondria

what type of chromosomes do most prokaryotic species have

most have one supercoiled chromosome in the nucleoid region of the cell

describe chloroplasts

most plant and algae cells have cholorplasts (they have a double membrane and contain their own DNA) They contain membrane-bound, flattened vesicles called thylakoids. They are stacked into piles called grant.

what are most vacuoles used for?

most vacuoles are used for storage of water and/or ions to help the cell maintain its normal volume

fimbriae

needlike projections that extend from the plasma membrane of some bacteria to promote attachment to other cells or surfaces

Ribosomal subunits are manufactured by the _____. A. smooth endoplasmic reticulum B. nucleolus C. lysosome D. peroxisome E. rough endoplasmic reticulum

nucleolus

flagella

on the cell surface that spin around to move the cell

what are internal compartments in many bacterial species referred to as?

organelles (little organs)

peroxisomes are the center of what type of reactions?

oxidation reactions

Which of these organelles produces H2O2 as a by-product? A. centrioles B. mitochondrion C. peroxisome D. flagellum E. nucleus

peroxisome

what are peroxisomes?

peroxisomes are globular organelles bound by a single membrane. They originate as buds from the ER.

The _____ is a selective barrier, regulating the passage of material into and out of the cell. A. nuclear envelope B. plasma membrane C. chloroplast D. nucleus E. lysosome

plasma membrane

Nucleus

power house of the cell that is large and highly organized

what is the function of ribosomes?

protein synthesis

in the endomembrane system, what is tightly regulated?

proteins and other large molecules

What happens in the RER lumen?

proteins are folded and glycosylated and carbs are attached to the protein

_____ are the sites of protein synthesis. A. Golgi apparatuses B. Microfilaments C. Ribosomes D. Mitochondria E. Peroxisomes

ribosomes

Which of these manufactures cellular membranes by adding membrane proteins and phospholipids to its own membrane? A. ribosomes B. lysosomes C. rough endoplasmic reticulum D. Golgi apparatus E. nucleolus

rough endoplasmic reticulum

define lysosomes

single-membrane-bound structures that contain approx 40 different digestive enzymes. Found only in animal cells

many bacteria contain plasmids, define plasmids

small, supercoiled, circular DNA, usually contain genes that help the cell adapt to unusual environmental conditions and are physically independent of the cellular chromosomes

the endomembrane system is composed of what?

smooth and rough ER and the golgi apparatus (this is the primary system for protein and lipid synthesis)

Where is calcium stored? A. smooth endoplasmic reticulum B. rough endoplasmic reticulum C. mitochondria D. microtubules E. centrioles

smooth endoplasmic reticulum

What is the solution outside of the thylakoids called?

stroma

describe the function of the cytoskeleton

the cytoskeleton organizes.... -all other organelles -cellular structures into a cohesive whole the cytoskeleton also aids in cell movement and helps transport materials within the cell

the cell wall of prokaryotes forms what

the exoskeleton

what do the fibrous proteins of the cytoskeleton do

the fibrous proteins move and change to alter

What is the function of the rough ER?

the function is synthesis of specific proteins that will be inserted into the plasma membrane, secreted to the cell exterior or shipped to an organelle

what is the function of the nucleus?

the function is to store information and process that info. It contains the cells chromosomes and ribosomal RNA synthesis (in the nucleolus)

what is the function of lysosomes

the function of lysosomes is to aid in digestion- wast processing

what is the function of the golgi apparatus

the functions include - processes, sorts, and ships proteins synthesized in the rough ER - cis side of the golgi apparatus receives products from the rough er - trans side ships them out to other organelles or the cell surface - membranous vesicles carry materials to and from the organelle

describe the golgi apparatus

the golgi app is formed by a series of stacked flat membranous sacs called cisternae. there is a distinct polarity or sidedness.

cytoskeleton

the inside of the cell is supported by a network of long, thin protein filaments

Which features are common to all cells? flagella and fimbriae the cell wall photosynthetic membranes the endoplasmic reticulum the plasma membrane chloroplasts mitochondria vacuoles the nucleus ribosomes lysosomes genetic information (DNA) in chromosomes cytoskeleton the cytoplasm

the plasma membrane, ribosomes, genetic information (DNA) in chromosomes, cytoskeleton, the cytoplasm

in eukaryotic cells, what makes it difficult for molecules to diffuse across the entire cell & how is the problem solved

the relatively large size of the eukaryotic cells ......... the problem is solved by breaking up the large cell volume into several smaller membrane-bound organelles

describe the rough ER

the rough ER is a network of membrane-bound tubes and sacs studded with ribosomes. The inside interior is called the lumen and it is continuous with the nuclear envelope

when does the sequence of events start in reference to endocytosis

the sequence begins when.... - macromolecules outside of the cell bind to receptors on the plasma membrane

Morphology

the study of the form of things

where are most proteins found in peroxisomes, mitochondria, and chloroplasts imported from?

they are mainly imported from cytosol

Which statement most accurately describes what happens to proteins that lack an ER signal sequence? A.)They bypass the ER but enter the Golgi apparatus. B.) They are released into the cytosol. C.) They are inserted into the plasma membrane. D.) They are inserted into the ER membrane but do not enter the ER lumen.

they are released into cytosol.

Molecular zip codes direct molecules to particular destinations in the cell. How are these signals read? A.)They bind to motor proteins. B.) They are glycosylated by enzymes in the Golgi apparatus. C.) They enter transport vesicles. D.) They bind to receptor proteins.

they bind to receptor proteins

since the inside surface of the nucleus is linked to fibrous proteins what does that linkage form?

they form a lattice-like sheet called the nuclear lamina

what do bacterial organelles do to generate chemical energy

they sequester enzymes to generate chemical energy from ammonium ions

What are vacuoles?

vacuoles are large, membrane-bound structures found in plants and fungi, some vacuoles are specialized for digestions. Some vacuoles contain digestive enzymes. Inside seeds, they are filled with proteins. In flower petals or fruits, they are filled with colorful pigments

exocytosis

where proteins are sent to the cell surface in vesicles that fuse with the plasma membrane to release their contents to the exterior wall