Biology Exam Review: Neural Pathways, Transport, Pathogens, and Physiology

A complete set of practice flashcards covering cell transport, neural transmission, plant physiology, disease transmission, and immunity based on lecture review notes.

What are the distinct functions of sensory neurons, motor neurons, and interneurons in neural pathways?

Sensory neurons transmit sensory information from receptors to the central nervous system, motor neurons convey signals from the central nervous system to effectors like muscles and glands, and interneurons process information and connect sensory and motor pathways.

What is the biological definition of a pathogen?

A pathogen is an agent or microorganism that causes disease in a host organism.

What is the structure and primary function of the cell membrane and its phospholipid bilayer?

The cell membrane consists of a phospholipid bilayer with hydrophilic heads and hydrophobic tails, acting as a selective barrier that regulates the entry and exit of substances to maintain cellular homeostasis.

How do prokaryotic cells differ from eukaryotic cells?

Eukaryotic cells contain a membrane-bound nucleus and specialized membrane-bound organelles, whereas prokaryotic cells lack a nucleus and membrane-bound organelles.

How do active transport, simple diffusion, osmosis, and facilitated diffusion differ?

Simple diffusion is the passive movement of solutes down a concentration gradient; osmosis is the passive diffusion of water across a semi-permeable membrane; facilitated diffusion uses transport proteins passively; and active transport moves molecules against a concentration gradient using cellular energy in the form of $\text{ATP}$.

What are the differences between hypotonic, hypertonic, and isotonic tonic states?

A hypotonic state has a lower solute concentration than the cell (causing net water movement into the cell), a hypertonic state has a higher solute concentration (causing net water movement out of the cell), and an isotonic state has an equal solute concentration with no net water movement.

What is the key difference between the lock and key model and the induced fit model of enzyme action?

The lock and key model asserts that the enzyme active site and substrate fit together perfectly without change, while the induced fit model states that the active site changes shape slightly upon substrate binding to optimize the fit.

What does a RIP diagram (optimal growth diagram) illustrate?

A RIP diagram shows the optimal growth or activity level of an organism or enzyme in response to environmental conditions like temperature or pH, indicating optimal zones and decline due to denaturation or stress.

Where do the light-dependent and light-independent reactions of photosynthesis take place in plant cells?

Light-dependent reactions occur in the thylakoid membranes of chloroplasts, whereas light-independent reactions occur in the stroma.

What are the primary methods behind disease transmission?

Disease transmission occurs through direct contact, indirect contact, airborne transmission via droplets, vector-borne transmission, and vehicle transmission through contaminated water or food.

What are histamines (histomeans) and what function do they serve in the body?

Histamines are chemical substances released by immune cells during an immune or allergic response that dilate blood vessels and increase capillary permeability to facilitate immune cell movement to sites of infection or injury.

What are the functions of xylem, phloem, and vascular tissue in vascular plants?

Xylem transports water and dissolved mineral nutrients upward from roots to leaves; phloem transports organic nutrients such as sugars throughout the plant; and vascular tissue provides overall structural support and bulk transport.

How do plant pathogens attack host plants?

Plant pathogens attack by breaching physical barriers (such as entering through stomata or cell walls), releasing enzymes to break down plant tissue, producing toxins, or manipulating host cell processes.

What are the definitions of active, passive, specific, and herd immunity?

Active immunity develops when the host's own immune system produces antibodies in response to an antigen; passive immunity is gained from receiving external antibodies; specific immunity involves targeted responses to distinct pathogens; and herd immunity occurs when widespread population immunity protects non-immune individuals.

What is the main difference between infectious and non-infectious diseases?

Infectious diseases are caused by transmissible pathogens and can spread between host organisms, whereas non-infectious diseases are caused by genetic, environmental, or lifestyle factors and cannot spread from organism to organism.

What strategies are used to prevent the spread of infectious disease?

Disease spread prevention strategies include proper hygiene and sanitation practices, vaccination programs, isolation or quarantine of infected individuals, vector control, and public health education.

How can xylem and phloem be identified in structural plant diagrams?

Xylem is identified by larger, vessel-like cells with thick walls positioned toward the interior of vascular bundles, while phloem features smaller sieve tubes and companion cells positioned toward the exterior of vascular bundles.

Why is the surface area to volume ($\text{SA:V}$) ratio significant within cell biology?

A higher $\text{SA:V}$ ratio enables efficient exchange of nutrients, gases, and wastes across the cell membrane relative to the internal cell volume, limiting cell size to ensure optimal metabolic transport.

How are transpiration, action potential, and thermoregulation defined?

Transpiration is the loss of water vapor from plant leaves via stomata; action potential is the rapid electrical impulse generated by a sudden change in membrane potential along a neuron; and thermoregulation is the process by which an organism maintains its internal body temperature within an optimal range.

How is depolarisation defined and described during transmission of nervous system messages?

Depolarisation occurs when an incoming signal alters cell membrane polarity by changing its charge chemistry; this shift pushes along adjacent nerve cells continuously to transmit the message while previous membrane sections return to their resting state.

What is the structure and question format of the upcoming biology exam?

The exam consists of 20 multiple-choice (multi-guess) questions and 12 short-answer questions (which do not require full sentence responses).