Cell Structure and Function Quiz

Cell Structure and Function

• Cells are the basic units of life, varying in complexity.
• All cells contain: cytoplasm (internal fluid); DNA (instructions for proteins); ribosomes (protein synthesis); and a plasma membrane (selective barrier).
• The plasma membrane's semipermeability controls what enters and leaves the cell.
• Space between cells contains interstitial fluid.
• Organelles are cell structures performing specific cellular functions.

Organelles

• Chloroplasts and mitochondria are organelles involved in energy acquisition.
• Chloroplasts are found in plants and carry out photosynthesis.
• Mitochondria break down glucose to release energy as ATP.
• Plants, bacteria, and fungi have a cell wall for support and protection.
• Vacuoles store water, food, or waste.
• Lysosomes break down waste.

Nucleus

• Complex cells contain nuclei, which store DNA.
• DNA's code creates proteins for various cellular functions.
• Endoplasmic reticulum (ER) surrounds the nucleus, aiding protein synthesis.
• Proteins are modified and packaged by the Golgi complex for use inside or outside cells.

Cell Division

• Cells divide for growth, repair, and reproduction.
• Each new cell needs a complete copy of the parent cell's DNA.
• Mitosis produces two identical daughter cells from one parent cell.
• DNA condenses into chromosomes during preparation for mitosis.
• Chromosomes separate, ensuring each daughter cell has a copy.
• Meiosis creates sex cells with half the parent cell's DNA.

Organization Levels

• Single-celled organisms carry out all life functions.
• Multicellular organisms have specialized cells organized into tissues, organs, and organ systems.

Tissues

• Tissues are groups of cells with similar functions.
• Four main tissue types: muscle (contraction), nervous (neurons), connective (support), and epithelial (protection, absorption, secretion).

Organs

• Organs are groups of tissues working together for a specific function.
• Examples include the heart, stomach, brain, uterus, and femur.

Organ Systems

• Organ systems are networks of organs performing a larger function.
• Examples: circulatory (nutrients, waste), skeletal (support, movement), and muscular.

Organism

• Organ systems combine to form the organism, an individual living entity.

Cell Functions

• Cell membrane regulates material passage into and out of cells.

Methods of Transport

• Passive transport (no energy): diffusion and osmosis.
• Active transport (requiring energy): moving substances against their concentration gradient.

Passive Transport

• Diffusion: movement of substances from high to low concentration.
• Osmosis: the diffusion of water. - Isotonic: equal solute concentration inside/outside the cell; no net movement of water. - Hypertonic: higher solute concentration outside the cell; water moves out of the cell. - Hypotonic: lower solute concentration outside the cell; water moves into the cell..

Cellular Respiration

• Aerobic respiration: glucose breakdown using oxygen.
  • Products: Water and carbon dioxide.
• Anaerobic respiration: happens without oxygen; less efficient, and produces lactic acid.

Genetics

• Genes are sections of DNA coding for traits; Alleles are different forms of a gene.
• Genotype describes the genes present; phenotype describes expressed traits.

Dominance and Codominance

• Dominant alleles require only one copy to be expressed; recessive alleles need two copies.
• Codominant alleles are both expressed equally in heterozygous individuals.

Segregation and Independent Assortment

• Segregation: each individual can only pass down one copy of each gene to offspring;
• Independent assortment: traits from different chromosomes separate into gametes independently; traits from close chromosomes separate together more often.

DNA

• Deoxyribonucleic acid (DNA) is a double helix containing inheritance instructions.
• DNA nucleotides consist of phosphate, deoxyribose sugar, and four nitrogenous bases: adenine, thymine, cytosine, and guanine.

RNA

• Ribonucleic acid (RNA) is involved in protein synthesis
  • Transcription: mRNA copies a gene sequence from DNA.
  • Translation: mRNA code is used by tRNA to create amino acid chains forming proteins.

Plants and Photosynthesis

• Plants (angiosperms) are multicellular, autotrophic, and usually have seeds encased in fruit.
• Photosynthesis: Plants use solar energy to make food (glucose) from carbon dioxide and water.
  • Chlorophyll absorbs the solar energy.
• Pollination: Angiosperms rely on pollinators like insects or birds.

Evolution

• Evolution: Life on Earth has changed throughout its history.
  • Fossil record, biogeography, comparative embryology, comparative anatomy, molecular biology provide evidence.

Natural Selection

• Natural selection: Organisms with favorable traits are more likely to survive and reproduce.
• Adaptations: favorable traits increasing survival.

Common Descent

• Common descent: all living species share a single common ancestor.

Classification of Organisms

• Taxonomy: classifying organisms based on characteristics.

  • Six Kingdoms: Archaebacteria, Eubacteria, Protista, Fungi, Plantae, Animalia

• Classification levels: domain, kingdom, phylum, class, order, family, genus, species.

Ecology

• Ecology studies interactions of organisms and their environment.
• Food chains and food webs depict energy flow and relationships.
• Trophic levels: the positions of organisms in a food chain (producers, primary consumers, etc.).
• Symbiosis: close relationships between species.

Biosphere and Ecosystems

• Ecosystem: biotic (living) and abiotic (nonliving) components.
• Biome: large ecosystem with similar climate/dominant plants (forests, deserts, tundra, grasslands).

Ecological Problems

• Pollution (Air, water, soil): harm to organisms and human health.
• Climate change: rising temperatures, extreme weather, ecosystem disruption, human health impacts.
• Biodiversity loss: habitat destruction leading to species extinction, ecosystem imbalance, and public health challenges (zoonotic diseases).

Microbiology

• Microbiology studies microorganisms, including bacteria, viruses, fungi, and protozoa.
• Importance in nursing: infection prevention and control via understanding microorganisms and the immune response.
• Importance in relation to aseptic techniques and sterilization in healthcare.

Laboratory Procedures

• Scientific experimentation: controlled experiments, variables (independent, dependent, constants), data collection.

Microscopes

• Light microscopes use light for magnification, up to about 1500x for living specimens.
• Electron microscopes use high-energy particles for magnification, enabling images of very small objects.

Types of Data

• Quantitative: numerical data.
• Qualitative: descriptive data.
• Continuous: numerical data within a range.
• Discrete: numerical data with specific values.