NLN NEX Science flashcards
NLN NEX Science · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Cell membrane function
- A selectively permeable phospholipid bilayer that controls which substances enter or leave a cell and helps maintain stable internal conditions.
- Photosynthesis inputs
- Carbon dioxide, water, and light energy are used by chloroplasts to produce glucose and oxygen during photosynthesis.
- Mitochondria role
- Organelles that produce most cellular ATP through aerobic respiration and are often called the powerhouse of the cell.
- Newton's first law
- An object remains at rest or in uniform motion in a straight line unless acted upon by a net external force.
- Ohm's law
- The relationship stating that voltage equals current multiplied by resistance, written as V = IR in electrical circuits.
- Kinetic energy formula
- Kinetic energy equals one-half the mass multiplied by the square of velocity, written as KE = ½mv².
- pH scale meaning
- A scale from 0 to 14 expressing hydrogen ion concentration; values below 7 are acidic, 7 is neutral, and above 7 is basic.
- DNA base pairing
- In DNA, adenine pairs with thymine and guanine pairs with cytosine through hydrogen bonds in the double helix.
- Left ventricle role
- The heart chamber that pumps oxygenated blood into the aorta and systemic circulation; its thick wall generates high pressure.
- Alveoli function
- Tiny lung sacs where oxygen diffuses into blood and carbon dioxide diffuses out across thin, moist surfaces.
- Nephron function
- The kidney's functional unit, which filters blood and adjusts water, electrolyte, and waste levels to form urine.
- Hemoglobin function
- An iron-containing protein in red blood cells that binds oxygen in the lungs and releases it in body tissues.
- Action potential
- A rapid electrical signal in a neuron caused by ion channels opening and changing the membrane's charge distribution.
- Insulin origin
- A hormone secreted by pancreatic beta cells that lowers blood glucose by promoting glucose uptake and storage.
- Systemic circulation path
- Blood flows from the left ventricle through arteries, capillaries, and veins, then returns to the right atrium.
- Skeletal muscle control
- Voluntary, striated muscle attached to bones that contracts under conscious nervous system control to produce movement.
- Gram-positive bacteria
- Bacteria with thick peptidoglycan cell walls that retain crystal violet stain and appear purple under a microscope.
- Antibiotic target
- Antibiotics commonly disrupt bacterial cell walls, protein synthesis, or DNA replication, which are processes absent or different in human cells.
- Virus replication
- Viruses must enter a host cell and use its machinery to copy their genetic material and make viral proteins.
- Antibody function
- Y-shaped proteins made by plasma cells that bind specific antigens and help neutralize pathogens or mark them for destruction.
- Vaccine mechanism
- A vaccine exposes the immune system to a harmless antigen, leading to memory cells that respond faster on later exposure.
- Nosocomial infection
- An infection acquired in a healthcare facility, often linked to invasive devices, surgery, or inadequate hand hygiene.
- Sterilization versus disinfection
- Sterilization destroys all microbial life including spores, while disinfection reduces pathogens on surfaces but may not eliminate spores.
- Normal microbiota
- Microorganisms that live harmlessly on or in the body and can compete with pathogens for nutrients and attachment sites.
- Independent variable
- The factor that a researcher deliberately changes or manipulates in an experiment to observe its effect.
- Dependent variable
- The outcome or response that is measured in an experiment and is expected to depend on the independent variable.
- Control group
- A comparison group that receives no treatment or a standard treatment and provides a baseline for evaluating experimental effects.
- Correlation meaning
- A statistical relationship in which two variables change together, but correlation alone does not prove that one causes the other.
- Median definition
- The middle value in an ordered data set; if there is an even number of values, it is the average of the two middle values.
- Standard deviation meaning
- A measure of how spread out data values are around the mean; a larger value indicates greater variability.
- Hypothesis definition
- A testable and falsifiable prediction about the relationship between variables that can be supported or rejected by evidence.
- Bar graph use
- A graph with rectangular bars used to compare quantities across discrete categories rather than show continuous trends.