Physiology Exam 2 Review Session Slides - Part II

What are calories used for in the body?

To provide fuel for ATP production

What is the difference between a calorie and a Calorie?

1 Calorie = 1000 calories

What are macronutrients?

Nutrients consumed in large amounts: proteins, fats, and carbohydrates

What are micronutrients?

Nutrients needed in small amounts: vitamins and minerals

Where are carbohydrates stored in the body?

Muscles, liver, and blood

Why are carbohydrates considered fast fuel?

They are readily available for ATP production

What happens if carbohydrate stores are insufficient?

The body increases oxidation of fats for energy

Which stores more energy: fats or carbohydrates?

Fats

What are saturated fats?

"Bad" fats

What are unsaturated fats?

"Good" fats

What are triglycerides?

Lipids used to produce ATP; excess is stored in adipose tissue or liver

What is cholesterol?

A lipid that can be consumed or synthesized by the body; used in plasma membranes and to make bile salts and steroids

What are eicosanoids?

Lipids derived from fatty acids involved in inflammation, blood clotting, tissue repair, and smooth muscle contraction

What are phospholipids?

Lipids that form plasma membranes and myelin sheaths

Why are proteins important?

They perform most functions in the body and require proper dietary balance

What can happen with excessive protein intake?

Rapid growth

What can happen with inadequate protein intake?

Muscle atrophy

What is nitrogen balance?

A state where nitrogen intake equals nitrogen excretion

What is the chief dietary source of nitrogen?

Proteins

How is nitrogen primarily excreted?

As nitrogenous wastes

What is positive nitrogen balance?

More nitrogen is ingested than excreted

What promotes positive nitrogen balance?

Growth hormones and sex hormones

What is negative nitrogen balance?

Body proteins are broken down for fuel

What is a major consequence of negative nitrogen balance?

Muscle atrophy

What do glucocorticoids do to proteins during stress?

Promote protein catabolism

What are minerals?

Inorganic elements originating from plants that make up about 4% of body mass

What mineral is most abundant in the body?

Calcium

What are the major functions of calcium?

Bones and teeth

What are the major functions of phosphorus?

Component of phospholipids, ATP, creatine phosphate, buffers, and nucleic acids

Which minerals act as enzyme cofactors?

Calcium, iron, magnesium, and manganese

Why is iron important?

It is essential for hemoglobin and myoglobin

What is chlorine used for in the body?

Formation of stomach acid (HCl)

What are mineral salts?

Electrolytes that regulate nerve and muscle function and body water distribution

Which vitamins are water-soluble?

Vitamins B and C

Which vitamins are fat-soluble?

Vitamins A, D, E, and K

What is anabolism?

Building larger molecules from smaller ones; requires energy input

What is catabolism?

Breaking larger molecules into smaller ones; releases energy

How much ATP is produced during glycolysis?

2 ATP

How much ATP is produced during the Krebs cycle?

2 ATP

How much ATP is produced during the electron transport chain?

28-30 ATP

What are NADH and FADH2?

Electron carriers used in ATP production

What is aerobic respiration?

ATP production requiring oxygen as the final electron acceptor

Where does most aerobic ATP production occur?

Mitochondria

What are the products of aerobic respiration?

Carbon dioxide, water, and about 38 ATP

What is anaerobic fermentation?

ATP production without oxygen

When does anaerobic fermentation occur?

When ATP demand exceeds oxygen supply

How much ATP does anaerobic fermentation produce?

2 ATP

What are the products of anaerobic fermentation?

2 ATP and lactic acid

Why is fermentation inefficient?

It produces much less ATP than aerobic respiration

Which organs do not favor fermentation?

Brain and heart

What is glycogenesis?

Synthesis of glycogen

What hormone stimulates glycogenesis?

Insulin

What is glycogenolysis?

Breakdown of glycogen into glucose

What hormones stimulate glycogenolysis?

Glucagon and epinephrine

Which cells can release glucose back into the bloodstream?

Liver cells

What is gluconeogenesis?

Synthesis of glucose from fats and amino acids

Is ATP a storage molecule?

No, ATP is used quickly after it is formed

What is lipogenesis?

Synthesis of fat from other sources

What is lipolysis?

Breakdown of fat for fuel

What is ketosis?

A state where insufficient glucose causes fatty acid breakdown and incomplete oxidation

What effect can ketosis have on blood pH?

Raises blood pH

What is the airflow pathway through the respiratory tract?

Trachea → Primary bronchi → Secondary bronchi → Tertiary bronchi → Bronchioles → Terminal bronchioles → Respiratory bronchioles → Alveoli

What is the conducting division of the respiratory system?

The portion responsible for airflow

What is the respiratory division of the respiratory system?

The distal gas exchange portion

What structures are included in the upper respiratory tract?

Nose through larynx

What structures are included in the lower respiratory tract?

Trachea through lungs

What is the glottis?

The vocal cords and the opening between them

What is the function of the epiglottis?

Protects the glottis and directs food into the esophagus

How is the infant larynx different from the adult larynx?

It sits higher, allowing breathing while swallowing

What is the trachea?

A rigid tube anterior to the esophagus

How many cartilaginous rings support the trachea?

16-20 C-shaped rings

What is the function of the trachealis muscle?

Adjusts airflow by expanding or contracting the trachea

What are the five major functions of the respiratory system?

Gas exchange, pH regulation, voice production, olfaction, and protection

What is the respiratory system's role in gas exchange?

Oxygen enters blood and carbon dioxide leaves

How does the respiratory system regulate blood pH?

By changing carbon dioxide levels

How does the respiratory system produce voice?

Air passing over vocal folds creates sound

How does the respiratory system contribute to olfaction?

Airborne molecules are detected in the nasal cavity

How does the respiratory system protect the body?

Prevents entry of microorganisms and removes them

What is the nasal vestibule?

The area just inside the nares

What forms the floor of the nasal cavity?

Hard palate

What is the nasal septum?

The partition dividing the nasal cavity

What are nasal conchae?

Bony ridges on the lateral walls of the nasal cavity

What are choanae?

Openings connecting nasal cavity to paranasal sinuses and nasolacrimal ducts

What is the function of cilia in the respiratory tract?

Sweep mucus and debris into the pharynx

What effect does smoking have on cilia?

It destroys them and increases sinus infections

What is the order of the pharynx regions?

Nasopharynx → Oropharynx → Laryngopharynx

What structures are found in the nasopharynx?

Auditory tubes and pharyngeal tonsil (adenoid)

What structures are found in the oropharynx?

Palatine and lingual tonsils

What are the boundaries of the laryngopharynx?

Hyoid bone to cricoid cartilage

How many lobes does the right lung have?

Three

How many lobes does the left lung have?

Two

What are Type I pneumonocytes?

Thin squamous cells responsible for gas exchange

What percentage of alveolar surface do Type I pneumonocytes cover?

90-95%

What are Type II pneumonocytes?

Cells that produce surfactant

What are dust cells?

Alveolar macrophages that clean inhaled debris

What is the visceral pleura?

The pleural layer attached directly to the lungs

What is the parietal pleura?

The pleural layer attached to the thoracic wall

What are the functions of the pleura?

Create a pressure gradient, assist inflation, prevent infection spread, and allow friction-free movement

What is pleural fluid?

Fluid between pleural layers that keeps them together and reduces friction

Which parts of the brain control unconscious breathing?

Medulla oblongata and pons