Conquer Biology OST Practice Test

Cells are the fundamental building blocks of all living organisms. They carry out essential functions necessary for life.

Mitochondria generate most of the cell's ATP, serving as the primary energy source. This is why they are often referred to as the powerhouse of the cell.

Photosynthesis allows plants to convert light energy into chemical energy stored in glucose. It is a fundamental process that supports life on Earth.

The cell membrane regulates the movement of substances into and out of the cell. This selective permeability is crucial for maintaining a stable internal environment.

DNA contains the genetic blueprint for the development and functioning of all living organisms. It is responsible for heredity and guides protein synthesis.

Ribosomes are the sites where proteins are synthesized by translating mRNA into polypeptide chains. They are essential for cell function and can be found free in the cytoplasm or attached to the rough ER.

Osmosis is the passive movement of water from an area of lower solute concentration to an area of higher solute concentration. It occurs across a semipermeable membrane without the input of energy.

During metaphase, chromosomes line up along the metaphase plate at the center of the cell. This proper alignment is critical for ensuring equal distribution of chromosomes to daughter cells.

DNA replication is a semi-conservative process, meaning each new DNA molecule includes one original strand and one newly synthesized strand. This mechanism maintains the integrity of genetic information between generations.

Chlorophyll is essential for absorbing sunlight, which is then used to drive the light-dependent reactions of photosynthesis. This absorbed energy is converted into chemical energy for the plant.

Approximately 10% of the energy from one trophic level is passed on to the next, with most energy lost as heat. This concept is fundamental to understanding energy flow in ecological systems.

Prokaryotic cells do not have a nucleus or any membrane-bound organelles, distinguishing them from eukaryotic cells. This simplicity is a defining characteristic of prokaryotes.

ATP, or adenosine triphosphate, is the molecule that directly provides energy for cellular functions. Its hydrolysis releases energy necessary for various metabolic processes.

Oxygen serves as the final electron acceptor in the electron transport chain, combining with electrons and protons to form water. This step is vital for efficient ATP production during aerobic respiration.

Enzymes act as catalysts by lowering the activation energy required for biochemical reactions, thereby speeding up the reaction rate. They are not consumed in the process, which allows them to be used repeatedly.

Crossing over during prophase I of meiosis facilitates the exchange of genetic material between homologous chromosomes. This process increases genetic diversity in the resulting gametes.

Natural selection favors individuals with beneficial alleles, thereby increasing their frequency in the population over time. This process drives adaptive evolution and improved fitness.

Aerobic respiration requires oxygen to efficiently produce ATP, whereas anaerobic respiration occurs without oxygen and yields less ATP. This difference is critical for understanding how cells adapt to varying oxygen conditions.

Intracellular signaling involves ligands that enter the cell and bind to internal receptors, directly influencing gene expression. This mechanism differs from extracellular signaling, where ligands interact with cell surface receptors.

Allopatric speciation occurs when populations are geographically separated, leading to reproductive isolation and genetic divergence. Over time, these isolated populations accumulate differences that result in the formation of new species.