Key Takeaways
- Health topics cover approximately 8 items (~13%) of the NEX Science section
- Essential nutrients: carbohydrates, proteins, fats, vitamins, minerals, and water
- Water-soluble vitamins (B, C) are not stored and need daily intake; fat-soluble vitamins (A, D, E, K) are stored in fat tissue
- Infectious diseases are caused by pathogens: bacteria, viruses, fungi, and parasites
- The immune system has two types of response: innate (nonspecific, immediate) and adaptive (specific, memory)
- Communicable diseases spread person-to-person; non-communicable diseases (cancer, diabetes, heart disease) do not
- Risk factors for chronic disease include poor diet, physical inactivity, smoking, excessive alcohol, and stress
- Homeostasis is the body's ability to maintain stable internal conditions despite external changes
Health, Nutrition & Disease
Health topics account for approximately 8 items (~13%) of the NEX Science section. These questions bridge basic science knowledge with real-world health applications.
Essential Nutrients
| Nutrient | Function | Sources | Daily Need |
|---|---|---|---|
| Carbohydrates | Primary energy source | Grains, fruits, vegetables | 45-65% of calories |
| Proteins | Build/repair tissue, enzymes, immune function | Meat, fish, beans, dairy | 10-35% of calories |
| Fats | Energy storage, insulation, cell membranes | Oils, nuts, avocado, dairy | 20-35% of calories |
| Vitamins | Regulate body processes, support immunity | Fruits, vegetables, dairy | Varies by vitamin |
| Minerals | Bone health, fluid balance, nerve function | Vegetables, dairy, meat | Varies by mineral |
| Water | Transport, temperature regulation, digestion | Beverages, foods | ~8 cups/day |
Vitamins: Water-Soluble vs. Fat-Soluble
| Category | Vitamins | Key Fact |
|---|---|---|
| Water-soluble | B vitamins (B1, B2, B3, B5, B6, B7, B9, B12), Vitamin C | Not stored; need daily intake; excess excreted in urine |
| Fat-soluble | Vitamins A, D, E, K | Stored in fat tissue and liver; can accumulate to toxic levels |
Key vitamins for nursing:
| Vitamin | Function | Deficiency |
|---|---|---|
| Vitamin A | Vision, immune function, skin | Night blindness |
| Vitamin B12 | Red blood cell formation, nerve function | Pernicious anemia, neuropathy |
| Vitamin C | Collagen synthesis, immune function, wound healing | Scurvy |
| Vitamin D | Calcium absorption, bone health | Rickets (children), osteomalacia (adults) |
| Vitamin K | Blood clotting | Excessive bleeding |
| Folic acid (B9) | DNA synthesis, fetal development | Neural tube defects in pregnancy |
| Iron (mineral) | Oxygen transport in hemoglobin | Iron-deficiency anemia |
| Calcium (mineral) | Bone/teeth, muscle contraction, nerve function | Osteoporosis |
Disease Concepts
Communicable vs. Non-Communicable
| Type | Spread | Examples |
|---|---|---|
| Communicable | Person-to-person via pathogens | Influenza, COVID-19, tuberculosis, HIV |
| Non-communicable | Not spread between people; caused by genetics, lifestyle, environment | Heart disease, diabetes, cancer, asthma |
Types of Pathogens
| Pathogen | Description | Example Diseases |
|---|---|---|
| Bacteria | Single-celled prokaryotes; some beneficial, some harmful | Strep throat, UTIs, tuberculosis |
| Viruses | Non-living; require a host cell to reproduce | Influenza, COVID-19, HIV, measles |
| Fungi | Can be unicellular or multicellular | Athlete's foot, yeast infections, ringworm |
| Parasites | Organisms that live on/in a host | Malaria, tapeworms, lice |
The Immune System
| Response Type | Speed | Specificity | Memory | Examples |
|---|---|---|---|---|
| Innate (nonspecific) | Immediate | General (fights all pathogens) | No | Skin barrier, inflammation, fever, phagocytes |
| Adaptive (specific) | Slower (days) | Targeted (specific pathogen) | Yes | Antibodies, T cells, B cells |
Vaccination stimulates the adaptive immune system to produce memory cells without causing disease, providing future protection.
Homeostasis
Homeostasis is the body's ability to maintain a stable internal environment despite changing external conditions.
Negative feedback loops (most common): The body detects a change and acts to reverse it.
- Example: Body temperature rises → sweat glands activate → body cools down → sweating stops
Positive feedback loops (less common): The body amplifies a change until a process is complete.
- Example: During labor, contractions stimulate oxytocin release → more contractions → continues until delivery
Chronic Disease Risk Factors
| Risk Factor | Associated Conditions |
|---|---|
| Smoking | Lung cancer, COPD, heart disease, stroke |
| Physical inactivity | Obesity, type 2 diabetes, heart disease |
| Poor diet | Obesity, hypertension, type 2 diabetes |
| Excessive alcohol | Liver disease, certain cancers, pancreatitis |
| Obesity | Type 2 diabetes, heart disease, joint problems |
| Stress | Hypertension, immune suppression, mental health disorders |
| Genetics | Various conditions; cannot be modified but can be managed |
Which of the following vitamins is fat-soluble?
What type of feedback loop is responsible for regulating body temperature?
Which pathogen requires a host cell to reproduce?
Which of the following are functions of proteins in the body? (Select all that apply)
Select all that apply
The body's ability to maintain a stable internal environment despite changing external conditions is called _____.
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A deficiency in Vitamin C can lead to:
Which of the following diseases is classified as COMMUNICABLE (infectious)?
Match each vitamin deficiency to its associated condition.
Match each item on the left with the correct item on the right
The innate immune system differs from the adaptive immune system because the innate system:
During a positive feedback loop:
The fat-soluble vitamins are A, D, E, and _____.
Type your answer below