Ace Your Bio Midterm Practice Test

A cell is the fundamental unit of life as it carries out all necessary life functions. Tissues, organs, and organ systems are made up of cells.

Mitochondria generate most of the cell's supply of ATP, acting as the powerhouse of the cell. Other organelles have distinct functions such as housing genetic material or synthesizing proteins.

Photosynthesis is the process by which plants convert sunlight into chemical energy. This process produces glucose and oxygen, which are vital for the plant's survival.

DNA stores the genetic blueprint necessary for the structure and function of all living organisms. Unlike proteins, carbohydrates, or lipids, DNA directly carries hereditary information.

Homeostasis refers to the process by which living organisms regulate their internal environment to maintain stable, constant conditions. It is essential for the proper functioning and survival of cells and organs.

Cellular respiration breaks down glucose to release energy stored in ATP, which fuels cellular activities. This process is vital for the survival and functioning of cells.

Oxygen is released as a byproduct during the light-dependent reactions of photosynthesis. This release is critical for sustaining aerobic life on Earth.

Ribosomes are the cellular structures where proteins are synthesized by translating mRNA. Other organelles perform different tasks, such as folding proteins or modifying them.

Chlorophyll is the main pigment in chloroplasts responsible for absorbing light energy for photosynthesis. Although carotenoids also absorb light, chlorophyll is the primary driver of the process.

In anaphase, the sister chromatids are separated and pulled toward opposite poles of the cell. This separation is key to ensuring that each daughter cell receives the correct number of chromosomes.

An allele is a variant form of a gene that can result in different traits among individuals. This variation is fundamental to genetic diversity within a population.

Meiosis is the cell division process that creates gametes with half the number of chromosomes to ensure genetic balance during sexual reproduction. This reduction is essential for maintaining species-specific chromosome numbers.

During metaphase, chromosomes align along the cell's equatorial plane in preparation for their separation. This alignment is crucial for ensuring that each daughter cell inherits an equal set of chromosomes.

The centromere is the region that physically connects sister chromatids until they are separated during cell division. It ensures that each daughter cell receives the correct genetic material.

The cell membrane acts as a selective barrier, regulating the passage of ions, nutrients, and waste products in and out of the cell. This regulation is essential for maintaining cellular homeostasis.

A mutation in the promoter region can alter the binding affinity of transcription factors, thereby affecting the level of gene expression. It usually does not directly change the amino acid sequence of the protein.

Natural selection favors individuals with beneficial heritable traits, enabling them to survive and reproduce more successfully. Over generations, this leads to evolutionary changes within the population.

A keystone species plays a critical role in maintaining the structure and balance of its ecosystem despite not necessarily being the most abundant. Its removal can lead to significant changes in ecosystem dynamics.

Crossing over during meiosis involves the exchange of genetic material between homologous chromosomes, creating new combinations of alleles. This recombination is a major source of genetic variation in sexually reproducing organisms.

The endosymbiotic theory suggests that mitochondria and chloroplasts originated from free-living prokaryotes that were engulfed by ancestral eukaryotic cells. This theory helps explain the unique features of these organelles, such as their own DNA and double membranes.