Chapter 1: The Cell Flashcards
____ cells contain a true nucleus enclosed in a membrane.
Eukaryotic
____ cells do not contain a nucleus
Prokaryotic
____ allows for the diffusion of molecules throughout the cell.
Cytosol
Within the nucleus, genetic material is encoded in ____. Which is organized into ____.
DNA Chromosomes
The nucleus is surrounded by the ____ or ____.
Nuclear membrane Envelope
____ a double membrane that maintains a nuclear environment separate and distinct from the cytoplasm.
Nuclear membrane Envelope
____ the entire content within the cell.
Cytoplasm
____ the fluid contained in the cell cytoplasm.
Cytosol
The genetic material (DNA) contains coding regions called ____.
Genes
Linear DNA is wound around organizing proteins known as ____, and is then further wound into linear strands called ____.
Histones Chromosomes
____ is where ribosomal RNA (rRNA) is synthesized.
Nucleolus
Mitochondria contains two layers called the _____ and ____ layer.
Outer Inner
The inner layer of the mitochondria is arranges into numerous inholdings calls ____.
Cristae
The Cristae contains ___.
molecules and enzymes for the ETC
The space between the inner and outer membrane of the mitochondria is called the ____.
Intermembrane Space
The space inside the intermembrance Space is called the ____.
mitochondrial matrix
Briefly describe the functions of each of the organelles: -Nucleus: -Mitochondrion: -Lysosome: -Rough Endoplasmic Reticulum: -Smooth Endoplasmic Reticulum: -Golgi Apparatus: -Peroxisome:
-Nucleus: stores genetic information and is the site of transcription -Mitochondrion: involved in ATP production (ETC and Oxidative phosphorylation) and apoptosis. Also, involved in Aerobic respiration -Lysosome:break down cellular waste products and molecules. Can be involved in apoptosis -Rough Endoplasmic Reticulum: synthesizes proteins -Smooth Endoplasmic Reticulum: synthesized lipids and does detoxification -Golgi Apparatus: packages, modifies, and distributes cellular products -Peroxisome:break down long chain fatty acids, synthesizes lipids, and contributes to the pentose phosphate pathway.
A child is diagnosed with an enzyme deficiency that prevents the production of hydrogen peroxide. What would the likely outcome be of such a deficiency?
Peroxisomes are dependent on hydrogen peroxide for their functions, so an enzyme deficiency that results in an inability to form hydrogen peroxide for their functions, so an enzyme deficiency that results in an inability to form hydrogen peroxide would likely result in an inability to digest very long chain fatty acids. These fatty acids would build up in peroxisomes until they displaced cellular contacts, ultimately resulting in cell death.
What are the predominant proteins in each cytoskeletal element? -Microfilaments: -Microtubules: -Intermediate Filaments:
-Microfilaments:composed of actin -Microtubules:composed of tubulin -Intermediate Filaments:differ by cell the, but may be composed of keratin, desmin, vimentin, and lamens.
How do the cytoskeletal structures of centrioles and flagella differ.
Centrioles: consists of nine triplets of microtubules around a hollow center. Flagella: consists of nine doubles on the outside, with two microtubules on the inside. (9-2 structure)
Classify each of the following cells as epithelial or connective tissue. -Fibroblast, which produces collagen in a number of organs. -Endothelial cells, which line blood vessels. -Alpha Cells, which produce glucagon in the pancreas. -Osteoblasts, which produce osteoid, the material that harden into bone. -Chondroblasts, which produce cartilage.
-connective -Epithelial -connective -epithelial -connective -connective
Where does transcription happen?
Nucleus
Where does translation happen?
Cytoplasm (inside ribosomes)
____ tissue supports the body and provides a framework for the epithelial cells to carry out their functions.
Connective
____ tissue cover the body and line its cavities, providing a means for protection in against pathogen invasion and desiccation.
Epithelial
Mutualistic Symbiotes
both humans and bacteria benefit from the relationship.
Parasites
They provide no advantage or benefit to the host and rather cause disease.
Chemotaxis
The ability of a cell to detect chemical stimuli and move toward or away from the cell.
Plasmids
Carry DNA that is not necessary for survival of the prokaryote and therefore is not considered part of the genome of the bacterium.
What is special about plasmids?
They bring an advantage which is ANTIBIOTIC RESISTANCE
Transformation (Define)
The integration of foreign genetic material into the host genome.
Conjugation (Define)
The transfer of genetic material from one bacterium to another across a conjugation bridge, a plasmid can be transferred from F+ cells to F- cells (Unidirectional Male+ to Female-), or a portion of the genome can be transferred from an Hfr cell to a recipient.
Transduction (Define)
The transfer of genetic material from one bacterium to another by a bacteriophage.
What are the three mechanisms of bacterial genetic recombination called?
Transformation Conjugation Transduction
What are the four phases of the bacterial Growth Curve? (Explain them)
- Lag Phase: Bacteria get used to environment; little growth. 2. Exponential Phase: Bacteria use available resources to multiple at an exponential rate. 3. Stationary Phase: Bacterial multiplication shows as resources are used up. 4. Death Phase: Bacteria die as resources become insufficient to support the colony.
A type of asexual reproduction characteristics in which there is equal nuclear and cytoplasmic division.
Binary Fission
Plasmids can also carry ____.
Virulence Factors
Virulence Factors
Traits that increase pathogenicity.
A specialized subset of plasmids capable of integrating into the genome of bacteria under specific circumstances.
Episomes
Why are viruses considered obligate intracellular parasites?
Viruses do not contain organelles such as ribosomes; therefore, in order to reproduce and synthesize proteins, viruses must infect cells and hijack their machinery.
Coronavirus, which causes the common cold, is described as an enveloped, single-stranded positive sense RNA virus. What does this indicate about the virus?
This description indicates that the virus contains an outer layer of phospholipids with an inner capsid. Within the capsid, there is single-stranded RNA that can be immediately translated to protein by the ribosomes of the host cells.
Briefly describe the pathway of retroviral nucleic acids from infection of a host cell to release of viral progeny.
- The nucleic acids enters as single-stranded RNA, which undergoes reverse transcription (using reverse transcriptase) to form double-stranded DNA. 2. This DNA enters the host genome and replicates with the host cell. 3. The DNA is transcribed into mRNA, which can be used to make structural proteins. 4. This mRNA doubles as the viral genome for new virions. 5. Once new virions are assembled from the structural proteins and mRNA (single-stranded RNA) genome, the virions can be released to infer other cells.
What are the differences between the lytic cycle and lysogenic cycle.
Lytic Cycle: Bacteriophages replicate in the host call in extremely high numbers until the host cell. lyses and releases the virions. Lysogenic Cycle: The bacteriophage genome enters the host genome and replicates with the host cell as a provirus. In the response to an appropriate stimulus, the provirus may leave the host genome and can be used to synthesize new virions.
How do prions cause disease?
Prions cause disease by triggering a change in the conformation of a protein from an alpha-helix to a beta-pleated sheet. This change reduces solubility of the proton and makes it highly resistant to a degradation.
Bacteriophages
viruses that specifically target bacteria.
Bacteriophages Capsid (Define) Tail Sheath (Define) Tail Fibers (Define)
Capsid: The protein coat (head) Tail Sheath: injects genetic material into a bacterium Tail Fibers: Help the bacteriophage recognize and connect to the correct host cell .
Positive-Sense
Single-stranded genome made of ribonucleic acid. The positive-sense genome can act as messenger RNA and can be directly translated into viral proteins by the host cell’s ribosomes.
Negative-Sense
Negative-strand RNA viruses are a group of related viruses that have negative-sense, single-stranded genomes made of ribonucleic acid. They have genomes that act as complementary strands from which messenger RNA is synthesized by the viral enzyme RNA-dependent RNA polymerase (RNA Replicase).
Negative-sense RNA virus must carry an ____ in the vision to ensure the complementary strand is synthesized.
RNA replicase
Single stranded RNA viruses may be ___ or ___.
Positive-Sense Negative-Sense
Retroviruses
enveloped, single stranded RNA viruses in the family retroviridae usually, the virions contains two identical RNA molecules.
Retroviruses carry an enzyme know an ____.
Reverse Transcriptase
How does reverse transcriptase work?
synthesizes DNA from single-stranded RNA. The DNA then integrates into the host cell genome, where it is replicated and transcribed as if it were the host cell’s own DNA.
