Cell Structure and Function Quiz

Cell Structure and Function

• Cells are the basic units of life, exhibiting a wide range of structures and functions.
• Prokaryotic cells (bacteria and archaea) are simpler, lacking membrane-bound organelles like a nucleus.
• Eukaryotic cells (plants, animals, fungi, protists) are more complex, possessing a nucleus and other membrane-bound organelles.
• Key organelles include the nucleus (controls cell activity), mitochondria (energy production), chloroplasts (photosynthesis - in plant cells), endoplasmic reticulum (protein synthesis and transport), Golgi apparatus (modifies and packages proteins), lysosomes (break down waste), and vacuoles (storage).
• Cell membranes are selectively permeable, controlling the passage of substances into and out of the cell.
• The cell membrane is primarily composed of a phospholipid bilayer containing embedded proteins.

Cellular Respiration

• Cellular respiration is the process by which cells break down glucose to release energy in the form of ATP.
• There are three main stages of cellular respiration: glycolysis, the Krebs cycle, and the electron transport chain.
• Glycolysis occurs in the cytoplasm and breaks down glucose into pyruvate.
• The Krebs cycle occurs in the mitochondria and further oxidizes pyruvate, producing NADH and FADH2.
• The electron transport chain occurs in the mitochondria's inner membrane, where electrons from NADH and FADH2 are passed along a chain, generating ATP through chemiosmosis.
• Aerobic respiration requires oxygen, while anaerobic respiration (fermentation) does not.

Photosynthesis

• Photosynthesis is the process by which plants and other organisms convert light energy into chemical energy in the form of glucose.
• Photosynthesis occurs in chloroplasts, specifically within the thylakoid membranes.
• The process has two main stages: the light-dependent reactions and the Calvin cycle.
• Light-dependent reactions capture light energy to produce ATP and NADPH.
• The Calvin cycle uses ATP and NADPH to convert carbon dioxide into glucose.
• Photosynthesis is essential for producing oxygen as a byproduct.

Genetics

• DNA is the hereditary material, carrying genetic information.
• DNA is a double helix structure composed of nucleotides.
• Genes are specific segments of DNA that code for proteins.
• The process of protein synthesis involves transcription (DNA to RNA) and translation (RNA to protein).
• Mutations are changes in DNA sequences, which can be beneficial, harmful, or neutral.
• Chromosomes are structures that organize DNA within the nucleus.

Evolution

• Evolution is the change in inherited characteristics of biological populations over successive generations.
• Natural selection is a key mechanism driving evolution, where organisms with advantageous traits are more likely to survive and reproduce.
• Adaptations are traits that enhance an organism's survival and reproduction in a particular environment.
• Speciation is the formation of new and distinct species in the course of evolution.
• Evolution is supported by evidence from fossils, comparative anatomy, molecular biology, and the distribution of organisms.

Ecology

• Ecology is the study of interactions between organisms and their environment.
• Ecosystems are composed of biotic (living) and abiotic (non-living) components.
• Organisms interact in various ways, including competition, predation, mutualism, and commensalism.
• Energy flows through ecosystems, typically starting with producers (plants) and moving through different trophic levels (consumers).
• Nutrient cycles, such as the carbon and nitrogen cycles, are essential for ecosystem function.

Microbiology

• Microbiology is the study of microorganisms, including bacteria, viruses, fungi, and protists.
• Microorganisms play crucial roles in various ecosystems, including decomposition, nutrient cycling, and disease.
• Different microbial groups have distinct metabolic capabilities and structures.
• Some microorganisms are beneficial (probiotics, food production, biotechnology), while others can cause diseases.
• Microbial interactions within and between species are essential to understanding their roles in ecosystems.