Human Body Part 1 Flashcards

Flashcards about the human body, part 1

What is the largest system in the levels of organization in nature?

The biosphere, which is the entire living surface of the Earth.

What are emergent properties?

New features created when individual components with their own unique functions work together.

Which two systems integrate and coordinate most body functions carried out by organs in the human body?

The nervous and endocrine systems.

What is the difference between endocrine and exocrine glands?

Endocrine glands produce hormones that have effects within the body, while exocrine glands produce substances that exit the body through a duct.

Which two glands are major players in organ system coordination and are connected by a stalk in the brain?

The hypothalamus and the pituitary gland.

How does darkness affect melatonin production?

Darkness stimulates production of melatonin by the pineal gland, lowering body temperature, metabolism, blood pressure & sugar.

What hormone is produced by adrenal glands when a person experiences a short-term stress stimulus?

Epinephrine, also called adrenaline.

What is homeostasis?

The coordinated efforts of an organism’s levels of structure to maintain a steady state.

What is a negative feedback loop?

A system that detects a deviation from a set point and instigates a response to bring conditions back to the set point.

What is vasodilation and how does it relate to thermoregulation?

Vasodilation is the dilation of blood vessels in the skin. It brings blood to the surface where sweating and evaporative cooling help lower body temperature.

What is the set point for blood sugar, and what hormones regulate it?

70-110 mg/ 100ml of glucose. Regulated by insulin and glucagon.

What is the difference between Type 1 and Type 2 diabetes?

Type 1 diabetes is characterized by insufficient insulin production, while Type 2 diabetes involves insulin resistance.

What is excretion and which organs are primarily responsible for it?

Excretion is the removal of water and wastes from the body via the urinary system. The primary organs are the kidneys.

What is the functional unit of a kidney, and approximately how many are in a kidney?

The nephron, and there are about one million nephrons in a kidney.

How blood plasma leaks from the glomerulus into the Bowman's capsule?

Blood plasma leaks from the glomerulus into the capsule through tiny pores in the blood vessel walls called fenestrae.

What is ultrafiltration?

The combination of high blood pressure with the structures of the capillary to force out plasma fluid.

What occurs in the proximal tubule of the nephron?

Water, salt, other ions, and small molecules are selectively reabsorbed into the renal cortex.

What is the structure of the nephron permeable to water by passive transport?

The descending limb of the loop of Henle.

What is the structure of the nephron permeable only to salt and not to water?

The ascending limb of the loop of Henle.

Which part of the nephron has the most selective reabsorption of water, salts, and other ions?

The proximal tubule.

Which part of the nephron can have its permeability to water adjusted?

The collecting duct.

What hormone is released from the posterior pituitary gland if the hypothalamus detects the osmolarity has risen above 300 mOsm/L?

ADH (antidiuretic hormone).

How does ADH affect the collecting ducts?

ADH increases water permeability of the collecting ducts by increasing the number of aquaporins.

What are the three main categories of hormones?

Amines, peptides, and steroids.

How do polar hormones interact with target cells?

Polar hormones cannot diffuse through the target cell’s plasma membrane so instead they bind as ligands on transmembrane receptors.

How do nonpolar hormones interact with target cells?

They diffuse through the plasma membrane and bind with a receptor internally, then stimulate a cellular response.

What are GPCRs and RTKs and how do they function?

GPCRs (G-protein coupled receptors) and RTKs (receptor tyrosine kinases) are transmembrane proteins that bind to hormones and initiate a transduction pathway.

What is the role of secondary messenger molecules in hormone signaling?

Secondary messenger molecules carry the message (transduction) to the target protein in the nucleus or cytoplasm.

What are some examples of cellular responses to hormone binding?

Converting glycogen to glucose, moving aquaporins to increase water permeability, and producing glucose transport proteins.

How do fat-soluble hormones stimulate gene expression?

They bind directly to a receptor protein, and the hormone and receptor become an active transcription factor.

What are the two circuits of the cardiovascular system?

The pulmonary circuit (to the lungs) and the systemic circuit (the rest of the body).

What are the three main types of blood vessels and their functions?

Veins (blood returning to the heart), arteries (blood going away from the heart), and capillaries (gas & material exchange).

What are the components of the flow of blood through the heart?

Blood flow: superior & inferior vena cava veins, right atrium, right ventricle, tricuspid valve, pulmonary valve, left & right pulmonary arteries, lungs, right & left pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic valve, aorta

What is the sinoatrial (SA) node?

A group of cells in the right atrium that can initiate an action potential.

What does the graph showing changes in blood pressure in the heart show?

How blood pressure opens and closes the valves of the heart.

What are systolic and diastolic pressure?

Systolic pressure is the pressure when the heart is contracting, and diastolic pressure is the pressure when the heart is relaxed.

What are the coronary arteries and why are they susceptible to occlusion?

The arteries that supply oxygenated blood to the heart. Susceptible to occlusion because high workload, high blood pressure on small diameter arteries w/ mechanical stress

What steps follow a blood vessel cut or broken/ruptured?

Vasoconstriction, platelet plug, clotting factors attract platelets, thrombin converts fibrogen to fibrin, fibrin creates mesh plug until mesh traps everything and scab forms.

How do gases diffuse through plasma membranes?

For unicellular and small multicellular organisms, gases diffuse through plasma membranes.

Describe the structure of the repiratory tract, starting with the entrances.

Air enters the mouth and/or nasal passages. Goes through the pharynx and enters the upper part of the trachea called the larynx (voice box), with the glottis (vocal chords).

What happens anatomically when we inhale?

The diaphragm contracts, pulling down on the thoracic (chest) cavity to create a negative air pressure inside the lungs.

What gas concentration do we use pressure?

The concentration of oxygen and carbon dioxide gases of air and blood is measured in partial pressures using units of millimeters of mercury (mm Hg).

What is hemoglobin (Hb)?

Hemoglobin (Hb) is the respiratory pigment that carries oxygen and some carbon dioxide in our blood.

What does pH dictate in regards to the blood's hemoglobins?

The pH of blood affects Hb’s ability to retain oxygen. Lowered pH alters the shape of Hb making it easier for oxygen to dissociate.

How does a fetus obtain oxygen from its mother?

A fetus gets its oxygen from its mother through the placenta and through fetal hemoglobin.

Fill in the blanks: volume is the volume we inhale and exhale under normal conditions. capacity is the difference in between the absolute maximum we can inhale and exhale. _ volume is air the lungs still have even after forcefully exhalting the last bit of air.

Tidal volume is the volume we inhale and exhale under normal conditions. Vital capacity is the difference in between the absolute maximum we can inhale and exhale. Residual volume is air the lungs still have even after forcefully exhalting the last bit of air.

What is the brainstem's role in heart regulation and ventilation?

External regulation of heart rate and regulation of ventilation (breathing) rate.