Cell Structure and Function Quiz

Cell Structure and Function

• Cells are the fundamental units of life, exhibiting a wide variety of shapes and sizes.
• Prokaryotic cells lack a nucleus and other membrane-bound organelles, while eukaryotic cells possess a nucleus and other organelles.
• Common cellular structures include the cell membrane, which regulates the passage of materials, the cytoplasm, the jelly-like substance inside the cell, and the nucleus, which houses genetic material.
• Specialized organelles in eukaryotic cells perform specific functions. Examples include mitochondria (energy production), ribosomes (protein synthesis), endoplasmic reticulum (protein and lipid synthesis), and Golgi apparatus (protein modification and packaging).
• Plant cells differ from animal cells primarily by having a cell wall, chloroplasts (for photosynthesis), and large central vacuoles.

Biological Molecules

• Four major classes of biological molecules are carbohydrates, lipids, proteins, and nucleic acids.
• Carbohydrates are primarily used for energy storage and structural support. Examples include glucose, starch, and cellulose.
• Lipids include fats, oils, and phospholipids, performing functions such as energy storage, insulation, and as structural components of cell membranes.
• Proteins are involved in diverse functions including structural support, catalyzing reactions (enzymes), transporting molecules, and acting as hormones.
• Nucleic acids, DNA and RNA, store and transmit genetic information. DNA carries the genetic code, while RNA plays a role in protein synthesis and other cellular processes.

Cellular Respiration

• Cellular respiration is the process cells use to break down glucose and produce ATP, the cell's primary energy currency.
• The process involves glycolysis, the Krebs cycle (citric acid cycle), and the electron transport chain.
• Glycolysis occurs in the cytoplasm and involves the breakdown of glucose into pyruvate.
• The Krebs cycle occurs in the mitochondrial matrix, further extracting energy from pyruvate.
• The electron transport chain occurs in the inner mitochondrial membrane, producing a large amount of ATP through oxidative phosphorylation.

Photosynthesis

• Photosynthesis is the process by which plants and other organisms convert light energy into chemical energy (glucose).
• This process occurs in chloroplasts, specifically in the thylakoid membranes where light-dependent reactions happen and the stroma where the light-independent reactions (Calvin cycle) occur.
• Light-dependent reactions capture light energy to generate ATP and NADPH.
• Light-independent reactions use ATP and NADPH to fix carbon dioxide and synthesize glucose.

Genetics

• Genes, the basic units of heredity, are segments of DNA that code for specific proteins.
• DNA (deoxyribonucleic acid) carries genetic information in a double helix structure.
• Transcription converts DNA to RNA, and translation converts RNA to protein.
• Mutations in DNA can alter the proteins produced, impacting an organism.
• Mendelian inheritance describes how traits are passed from parents to offspring.

Ecology

• Ecology studies the interactions between organisms and their environment.
• Ecosystems consist of biotic (living) and abiotic (non-living) components.
• Energy flows through ecosystems via food chains and food webs.
• Nutrient cycles (e.g., carbon and nitrogen) are essential for ecosystem function.
• Organisms in an ecosystem exhibit various interactions like competition, predation, and symbiosis.
• Biotic factors include living things in an ecosystem (e.g., producers, consumers, decomposers).
• Abiotic factors encompass the non-living components of an ecosystem (e.g., temperature, water, sunlight).

Evolution

• Evolution is the process of change in the heritable characteristics of biological populations over successive generations.
• Natural selection is a key mechanism where organisms with advantageous traits are more likely to survive and reproduce.
• Evidence for evolution comes from fossils, comparative anatomy, molecular biology, and biogeography.
• Speciation is the process by which new species arise.
• The diversity of life on Earth arose through evolutionary processes.

Biotechnology

• Biotechnology utilizes biological systems, organisms, or their components to develop various products, technologies, or processes.
• Modern biotechnology includes genetic engineering, where scientists manipulate an organism's genetic material to introduce new traits or modify existing ones.
• Recombinant DNA technology creates new combinations of genetic materials.
• Biotechnology is relevant in medicine, agriculture, and industry.

Test your understanding of cell structure and function, including differences between prokaryotic and eukaryotic cells. Explore specialized organelles and their roles, as well as the unique features of plant cells. This quiz covers essential concepts related to biological molecules as well.