BIO Ch. 1 The Cell

Question 1

What is the role of the cytosol?

Answer 1

it allows for the diffusion of molecules throughout the cell

Question 2

What is the role of the nuclear envelope?

Answer 2

separates the nucleus from the cytoplasm

Question 3

What is the role of the nuclear pore?

Answer 3

allows for selective 2-way exchange of material b/w the cytoplasm and nucleus

Question 4

What is the role of the mitochondrial membranes?

Answer 4

outer - serves as a barrier b/w the cytosol and the inner environment of the mitochondrion
inner - folded into cristae that increase the surface area for the ETC
intermembrane/matrix - pumps protons that flow through ATP synthase to establish the proton motive force

Question 5

What is the role of the nucleolus?

Answer 5

It is where ribosomal RNA is synthesized

Question 6

What is cytoplasmic or extranuclear inheritance?

Answer 6

the transmission of genetic material independent of the nucleus.
ex: the mitochondria have it’s genes and replicate independently of the nucleus via binary fission

Question 7

What is the role of the lysosomes?

Answer 7

contains hydrolytic enzymes that can break down substances ingested by endocytosis and cellular waste products, and autolysis of the cell occurs

Question 8

What is the role of the endosomes?

Answer 8

transport, package, and sot cell material traveling to and from the membrane, trans-golgi, or the lysosomal pathway for degradation

Question 9

What is the role of the RER?

Answer 9

studded with ribosomes, which permit the translation of proteins destined for secretion directly into its lumen

Question 10

What is the role of the SER?

Answer 10

utilized primarily for lipid synthesis, and drug detoxification, and can transport proteins from the RER to the Golgi apparatus

Question 11

What is the role of the peroxisomes?

Answer 11

contains hydrogen peroxide that breaks down very long FA chains via b-oxidation, participates in the synthesis of phospholipids, and contains some of the enzymes involved in the PPP

Question 12

What is the role of the cytoskeleton?

Answer 12

provides stability, rigidity, and cell structure, and helps the cell maintain its shape. made up of microfilaments, microtubules, and intermediate filaments

Question 13

What is the role of the microfilaments?

Answer 13

helps to form cleavage furrows during cytokinesis In mitosis

Question 14

What is microfilament made of?

Answer 14

made up of solid polymerized rods of actin

Question 15

What is the role of actin?

Answer 15

actin filaments are organized into bundles and networks and are resistant to compression and fracture, protecting the cell. Actin also interacts with myosin to generate muscle contraction

Question 16

What are microtubules made of?

Answer 16

hollow polymers of tubulin proteins

Question 17

What is the diff b/w cilia and flagella?

Answer 17

cilia moves materials along the surface of the cell, while flagella is involved in the movement of the cell itself

Question 18

What is the structure of cilia and flagella?

Answer 18

9 pairs of microtubules form an outer ring with 2 microtubules In the center (9 + 2 structure)

Question 19

What is the role of centrioles?

Answer 19

organized centers of microtubules and are structures as 9 triples of microtubules with a hollow center

Question 20

What is the role of intermediate filaments?

Answer 20

involved in cell-to-cell adhesions or maintain the overall integrity of the cytoskeleton, and they help to anchor other organelles like the nucleus

Question 21

What is the difference in the layers of epithelial?

Answer 21

simple - have 1 layer
stratified - have multiple layers
pseudostratified - appears to have multiple layers due to differences in cells but in reality, are one 1 layer

Question 22

What are the different shapes of epithelial?

Answer 22

cubodal - cube shapes
columnar - long and thin
squamous - flat and scalelike

Question 23

What is the role of connective tissue?

Answer 23

support the body, provide a framework for epithelial cells to carry out their functions

Question 24

What is the diff in the contribution of epithelia vs. connective tissue?

Answer 24

epithelial cells contribute to the parenchyma (functional part) of an organ, connective tissue is the main contributor to the stroma or support structure by secreting materials to form an extracellular matrix

Question 25

What are examples of intermediate filaments?

Answer 25

filamentous proteins such as keratin, desmin, vimentin, and lamins

Question 26

What are examples of cells that are composed of epithelial cells?

Answer 26

nephrons in the kidney, hepatocytes in the liver, acid-producing cells of the stomach, endothelial cells, a-cells

Question 27

What are examples of connective tissue?

Answer 27

bone, cartilage, tendons, ligaments, adipose tissue, blood

Question 28

What are the different shapes of bacterial cells?

Answer 28

spherical = cocci
rod = bacilli
spiral = spirilla

Question 29

What is the role of the Golgi apparatus?

Answer 29

consist of stacked membrane-bound sacs in which cellular products can be modified, packaged, and directed to specific cellular locations

Question 30

What are the 4 classifications of bacteria?

Answer 30

obligated aerobes, obligated anaerobes, facultative anaerobes, aerotolerant anaerobes

Question 31

What is an obligate aerobe?

Answer 31

require oxygen for metabolism

Question 32

What is an obligate anaerobe?

Answer 32

cannot survive in oxygen-containing environments, and can only carry out anaerobic metabolism

Question 33

What is a facilitated anaerobe?

Answer 33

can survive with or w/o oxygen and will be used either for metabolism

Question 34

What is an aerotolerant anaerobe?

Answer 34

cannot use oxygen for metabolism, but can survive in oxygen-containing environments

Question 35

What is the diff in straining b/w gram-negative and positive?

Answer 35

gram-positive bacteria turn purple, while gram-negative bacteria turn pink-red

Question 36

What is the diff b/w gram-negative and positive?

Answer 36

Gram-positive bacteria have a thick cell wall composed of peptidoglycans and lipoteichoic acid
gram-negative bacteria have a thin cell wall composed of peptidoglycan and an outer membrane containing phospholipids and lipopolysaccharide

Question 37

What is the diff b/w eukaryotic and prokaryotic ribosomes?

Answer 37

prokaryotic ribosome - 30S and 50S
eukaryotic - 40S and 60S

Question 38

What is transformation?

Answer 38

the acquisition of genetic material from the environment, which can be integrated into the bacterial genome

Question 39

What is conjugation?

Answer 39

the transfer of genetic material from one bacterium to another across a conjugated bridge

Question 40

What is transduction?

Answer 40

the transfer of genetic material from one bacterium to another using bacteriophage as a vector

Question 41

What are transposons?

Answer 41

genetic elements that can inset into or remove themselves from the genome

Question 42

What are the bacterial growth phases?

Answer 42

lag - bacteria get used to the environment; little growth during this time
exponential - bacteria are available resources to multiply at an exponential rate
Stationary-bacterial multiplication ceases as resources are used up
death - bacteria die when resources are insufficient to support the colony

Question 43

What is a bacteriophage?

Answer 43

viruses that target bacteria

Question 44

How does a virus infect cells?

Answer 44

by attaching to specific receptors, and then either fusing with the plasma membrane, being brought in by endocytosis, or injecting their genome into the cell

Question 45

What are the 2 life cycles of bacteriophage?

Answer 45

lytic - the bacteriophage produces massive numbers of new virions until the cell lyses.
lysogenic - virus integrates into the host genomes as a provirus or prophage, which can then reproduce along with the cell, and enter the lytic phase at a later time

Question 46

What are prions?

Answer 46

infectious proteins that trigger the misfolding of other proteins are usually converted from an a-helical structure to a b-pleated sheet, which decreases the solubility and degradability of the misfolding protein

Question 47

What are virons?

Answer 47

plant pathogens that are small circles of complementary RNA that can turn off genes, resulting in metabolic and structural derangements of the cell and potential cell death