Photosynthesis Quiz

Photosynthesis

• Photosynthesis is performed by autotrophic organisms, including plants and algae.
• Heterotrophic organisms, like animals, obtain nutrients by consuming other organisms.
• Photosynthesis requires carbon dioxide and water, using light energy.
• The products are oxygen and glucose, a carbohydrate.
• Glucose stores energy, originally from light absorbed during photosynthesis.
• Photosynthesis occurs within chloroplasts, specialized organelles.
• Chloroplasts include flattened membrane-bound thylakoids.
• Thylakoids stack into grana, connected by lamellae.
• The stroma is the fluid within the chloroplast.

Light-Dependent Reactions

• Light-dependent reactions happen on thylakoid membranes.
• They require light for function.
• These reactions yield ATP and NADPH, essential coenzymes.
• Water is split during light-dependent reactions, releasing oxygen.

Light-Independent Reactions

• Light-independent reactions, also known as the Calvin cycle, take place in the stroma.
• They don't need light.
• ATP and NADPH generated in the light-dependent reactions fuel glucose production from carbon dioxide.
• This process stops if ATP and NADPH levels fall due to lack of light.

Cell Structure and Function

• Cells are the fundamental units of life, exhibiting variation in shapes and sizes.
• Cells contain various organelles, each with specific functions.
• The cell membrane controls what enters and exits the cell.
• The cytoplasm is a gel-like substance in the cell, encapsulating organelles.
• The nucleus, frequently the largest organelle, houses the cell's DNA.
• Mitochondria generate energy through cellular respiration.
• Ribosomes synthesize proteins.
• The endoplasmic reticulum (ER) modifies proteins and synthesizes lipids.
• The Golgi apparatus processes and packages proteins for secretion.
• Lysosomes contain enzymes for intracellular digestion.
• Vacuoles are storage sacs, common in plant cells.
• Plant cells have a rigid cell wall for support.
• Chloroplasts, found only in plant cells, are the sites of photosynthesis.

Cell Processes

• Cellular respiration converts glucose into ATP (adenosine triphosphate).
• Photosynthesis, unique to plants, converts light energy into chemical energy stored in glucose.
• DNA replication produces identical copies of the DNA.
• Transcription converts DNA into RNA.
• Translation uses RNA to synthesize proteins.
• Mitosis creates two identical daughter cells from a parent cell.
• Meiosis produces genetically diverse cells for gamete generation.

Biological Molecules

• Carbohydrates (sugars and starches) are main energy sources.
• Lipids (fats and oils) store energy and form cell membranes.
• Proteins have diverse functions, including structural support, catalysis (enzymes), and transport.
• Nucleic acids (DNA and RNA) store and transmit genetic information.

Biological Systems

• Organisms exhibit emergent properties due to interactions among parts.
• Cells create tissues, tissues form organs, and organs make up organ systems.
• Organ systems work together for homeostasis, maintaining internal stability and responding to the environment.
• Examples of organ systems include the digestive, respiratory, circulatory, nervous, and musculoskeletal systems.

Genetics

• Genes, segments of DNA, control organismal traits.
• Alleles are different gene versions.
• Genotype is the genetic information, while phenotype is observable traits.
• Mendelian genetics describes patterns of simple trait inheritance.
• Non-Mendelian genetics shows inheritance beyond simple dominant/recessive relationships.
• Mutations alter DNA sequence and can have various effects.
• Genetic engineering manipulates genes for desired traits.

Evolution

• Evolution is the change in heritable characteristics within populations over time.
• Natural selection favors traits beneficial for survival and reproduction.
• Adaptation is the process that helps organisms be better suited to environments.
• Common ancestry connects all living organisms through evolutionary history.
• Speciation is the emergence of new species.

Ecology

• Ecology studies relationships between organisms and their environment.
• Ecosystems have biotic (living) and abiotic (nonliving) components.
• Energy flows through ecosystems via food chains and webs.
• Nutrient cycles, like carbon and nitrogen, are critical for ecosystem health.
• Biodiversity is the variety of life, from genes to ecosystems.

Classification of Organisms

• Organisms are categorized into taxonomic groups (domain to species) based on shared characteristics.
• The three domains of life are Bacteria, Archaea, and Eukarya.
• Eukarya includes protists, fungi, plants, and animals.
• Phylogenetic trees illustrate evolutionary relationships among organisms.