Biology Midterm Preparation: Cellular Structures and Functions

All cells share fundamental components such as plasma membrane, cytoplasm, ribosomes, dissolved enzymes, water, and DNA, while the incorrect answers represent specific organelles or structures found only in certain types of cells.

Prokaryotes do not contain mitochondria and chloroplasts as those are found in eukaryotic cells. Similarly, cytosol and endoplasmic reticulum are present in both prokaryotic and eukaryotic cells. The nucleus and Golgi apparatus are specific to eukaryotic cells.

Eukaryotic cells belong to kingdoms Protist, Plantae, Fungi, and Animalia. Bacteria, Archaea, and viruses are not considered eukaryotic kingdoms.

Compartmentalization in cells helps to separate and organize different cellular processes, which increases the efficiency of cellular functions and allows for more surface area for important interactions to occur.

The correct answer is 'to synthesize proteins'. The Rough Endoplasmic Reticulum (RER) is responsible for protein synthesis in the cell, where ribosomes attached to its surface help in the assembly of proteins.

Cotranslational transport involves the protein being transported to the ER while translation is still ongoing, allowing for immediate integration into the ER membrane or lumen.

The correct types of transport in the Golgi involve vesicular transport and cisternal maturation, as described in the answer. The incorrect answers provided do not accurately depict the transport processes that occur in the Golgi apparatus.

Proteins are sent to their correct cellular location by a carbohydrate tag, which acts as a signal for transport to the appropriate organelle.

Lysosomes are membrane-bound organelles containing digestive enzymes. They are responsible for breaking down cellular waste and recycling materials in the cell. The acidic environment inside a lysosome is maintained by a proton pump.

Peroxisomes are organelles responsible for breaking down lipids and detoxifying harmful substances in the cell.

The endosymbiosis theory explains the origin of mitochondria and chloroplasts in eukaryotic cells, highlighting the symbiotic relationship between different types of organisms within a cell.

The cytoskeleton is made up of microfilaments, intermediate filaments, and microtubules, which provide structural support, cell motility, and intracellular transport within the cell.

Protein fibers in cells refer to structures like microfilaments, intermediate filaments, and microtubules which have specific functions related to cell movement, support, and division. The incorrect options provided are organelles with different functions than protein fibers.

Microtubule motors in flagella exhibit directional movement based on the type of motor protein present. Dynein moves towards the - end (towards the cell body), while kinesin moves towards the + end (outside of the cell). Understanding this directional movement is crucial in understanding flagellar motility.

The Griffith experiment is a classic experiment in microbiology that showcased the transformation of genetic material between different strains of bacteria and the implications of this exchange.

Avery's experiment built upon Griffith's work and ultimately proved that DNA was the molecule responsible for genetic transformation.

The Hershey and Chase experiment was a groundbreaking study that conclusively proved that DNA, and not protein, is the genetic material of viruses. By labeling viral DNA and protein with radioactive isotopes and tracking their entry into host cells, they demonstrated that only the DNA from the virus is injected and acts as the genetic material.

The correct answer refers to three models proposed for DNA replication. Semi conservative, conservative, and dispersive are the three theories that have been studied to understand how DNA replicates.

The Meselson and Stahl experiment was specifically designed to determine the mechanism of DNA replication by using isotopic labeling and density gradient centrifugation.

Prokaryotes and eukaryotes have distinct differences in their replication processes, including the number of replication forks, the shape of DNA, and the presence of leading/lagging strands.

In DNA replication, the leading strand is synthesized in the same direction as the replication fork, allowing for continuous replication. The lagging strand is synthesized away from the replication fork in short, discontinuous fragments called Okazaki fragments. This process requires multiple enzymes to facilitate the synthesis of both strands.

The proteins involved in DNA replication and function are specific to the replication process itself and are not directly related to transcription or translation, which are processes involving RNA polymerase, transcription factors, and ribosomes. As such, these incorrect answers are not part of the DNA replication and function proteins.

Telomerase is the enzyme responsible for repairing short ends of DNA strands by bringing an RNA template to lengthen the 3' end. This process involves the addition of repeating sequences, an essential mechanism for maintaining genomic stability.

Cell division involves a series of steps that ensure accurate replication and distribution of genetic material to daughter cells. The correct steps include: replicating DNA, separating DNA to two ends of the cell, and dividing the cytoplasm. The incorrect answers provided do not accurately represent the stages of cell division.

The correct stages that correspond with the sections on the curve are G2, S+M, and G2+G1. The incorrect answers provided do not accurately match the stages to the sections on the curve.

Cell division primarily serves the purpose of reproduction and growth by creating new cells. Repair and maintenance, energy production, and waste elimination are functions performed by other cellular processes.

Mitosis is a process that includes distinct stages - prophase, prometaphase, metaphase, anaphase, and telophase, which eventually leads to the division of the cell. Cytokinesis is actually the last stage of the cell cycle, not mitosis itself. Telophase is the stage where chromosomes move to opposite ends of the cell, not align at the equator. Interphase occurs before mitosis, where the cell prepares for division but is not a stage of mitosis.