Mod 8 Flashcards
Define metabolic efficiency.
Conditions within the body must be maintained at a constant level for optimal metabolic efficiency.
What environment do body cells live in?
Body cells live in extracellular fluid.
What do enzymes control in the cell?
Enzymes control all metabolic activities within the cell.
What are two constant factors needed for enzyme functioning?
Temperature and pH (optimal range).
What is homeostasis?
The process by which organisms maintain a relatively stable internal environment in response to changes.
What are the two stages of homeostasis?
Detecting changes and responding to them.
What is a negative feedback system?
A system where a response reverses a change to restore stability.
What are the roles of thermoreceptors?
Thermoreceptors detect temperature changes and send information to the hypothalamus.
What is the role of the hypothalamus in temperature regulation?
The hypothalamus is the control center for temperature regulation.
How does the body warm itself?
Heat gain center activates responses like raised hairs, vasoconstriction, shivering, and increased metabolism.
Define glucose homeostasis.
The regulation of blood glucose levels, normally about 90mg/100mL.
How does insulin lower blood glucose levels?
Insulin facilitates glucose transport from the blood to the cells and promotes glucose storage in the liver as glycogen.
How does glucagon increase blood glucose levels?
Glucagon stimulates the liver to break down glycogen and release glucose into the blood.
What are the main components of the nervous system?
The Central Nervous System (CNS) and the Peripheral Nervous System (PNS).
What is the function of the CNS?
The CNS processes and regulates body functions and coordinates responses.
Define hormone.
A chemical messenger produced by endocrine glands and released into the bloodstream.
What is the role of insulin and glucagon?
They regulate blood glucose levels.
What does antidiuretic hormone (ADH) regulate?
Water balance, osmolarity, and blood pressure homeostasis.
What does aldosterone regulate?
Blood pressure, by managing sodium and potassium levels in the blood.
What do thyroid hormones (T3 and T4) control?
They control metabolism, converting food into energy.
What is an axon surrounded by?
An axon is surrounded by a fatty insulating cover called the myelin sheath.
What are the types of neurons?
Sensory neurons, motor neurons, and connector neurons.
Define adaptation.
A feature that enables an organism to survive and reproduce in different environments.
Define endotherms.
Warm-blooded organisms that use internal processes to regulate body temperature.
Define ectotherms.
Cold-blooded organisms with body temperatures that fluctuate with the environment.
What is countercurrent exchange in penguins?
A process where closely aligned veins and arteries allow heat recycling to maintain internal body temperature.
List some behavioral adaptations to stay cool in endotherms.
Burrowing, stretching out, nocturnal activity, seeking shade, cooling down in water, and evaporative cooling (licking saliva).
List some structural adaptations to stay warm in endotherms.
Insulation (feathers, fur, blubber), small surface area-to-volume ratio, and countercurrent heat exchange.
What are the main adaptations in plants for water balance?
Thick waxy cuticles, reduced leaves, photosynthetic stems, sunken stomata, and water storage.
What are non-infectious diseases?
Diseases not caused by pathogens and not transmitted from one organism to another.
What causes genetic diseases?
Mutations in genes or chromosomes, or abnormal cell division.
What causes nutritional diseases?
Imbalanced diets, undernutrition (e.g., iron deficiency), or overnutrition (e.g., obesity).
What is cancer?
Uncontrolled cell growth and division that invades tissues and disrupts normal body functions.
Define epidemiology
Study of patterns of diseases in populations (distribution, frequency, and causes) to establish measures to prevent and control the spread of disease.
What are the key purposes of epidemiology?
Describing patterns, identifying causes of disease, and providing data essential for management, evaluation, and planning of treatment and control services.
What is the focus of public health data collection?
Surveillance to determine time, place, and purpose (who, where, when), essentially through descriptive studies.
What are the steps in epidemiological assessment?
Inference to draw conclusions and hypothesis testing to determine how and why.
What is intervention in epidemiology?
Action to prevent risk factors and promote healthy behaviors.
What is descriptive epidemiology?
The first type of study when investigating a disease, providing information about patterns, affected population sections, geographical location, and specific time periods.
What is analytical epidemiology?
Studies used to collect more data and test hypotheses about likely causes of disease by measuring associations between a factor and a disease.
What are case-control studies?
Studies comparing individuals with a disease (case) to those without (control), identifying differences in exposures that could cause the disease.
What are the advantages of case-control studies?
Inexpensive, smaller sample sizes, less time-consuming.
What are the disadvantages of case-control studies?
Difficult to select a control group representative of the entire population, inefficient for rare exposures, can only study one outcome at a time.
What are cohort studies?
Studies two or more groups without the disease, where one group is exposed to a risk factor and the other is not, followed over time to compare the incidence of the disease.
What are the advantages of cohort studies?
Shows exposure and outcome link, calculates incidences and prevalence, and can study multiple diseases.
What are the disadvantages of cohort studies?
Expensive, time-consuming, high dropout rate, requires a large sample size.
What are morbidity and mortality?
Morbidity is the number of cases of a disease; mortality is the percentage of the population that dies from the disease.
What are the factors for a valid epidemiological study?
Large sample size, extended time, representative participants, use of control groups, valid data collection, statistical analysis, peer review.