Biology Body System

The Circulatory System

Transport system that connects the organs of exchange w/ body cells, transports blood throughout the body (aka cardiovascular system)

Order of blood flow (circulatory system)

The IVC and SVC (Inferior and Superior Vena Cava) get oxygen-poor blood from the body and is transported which goes to the right atrium it collects the oxygen poor blood and goes through the tricuspid valve(between right atrium and right ventricle) to the right ventricle which then goes to the pulmonary artery which carries the deoxygenated blood to the lungs. This is where gas exchange happens (in the alveoli) and goes to the pulmonary veins which now has oxygen rich blood which goes to the left atrium which goes through the mitral valve to the left ventricle which is the chamber that pumps blood with the greatest force to send it to the rest of the body. It goes through the aortic valve to the aorta which is the main artery which carries the blood to the rest of the body which goes to body cells

heart and blood vessels and valves (circulatory system)

there are 4 chambers, 2 atrium (upper) 2 ventricle(lower); arteries:carries blood away from heart, holds a lot of force because it is thick to withstand the pressure of the blood, capillaries: thinnest vessels, where gas exchange happens, veins: carries blood to the heart, valves prevent the backward flow of blood: tricuspid valve between right atrium and right ventricle, mitral valve between left atrium and left ventricle, aortic valve, between left ventricle and aorta

gas exchange in circulatory system

when the pulmonary artery receives blood from the right ventricle it carries it to the lungs where gas exchange happens, the oxygen poor blood turns into oxygen rich blood (oxygen goes in the blood, carbon dioxide diffuses out) then it goes to the pulmonary vein where the oxygenated blood gets carried to the heart, the left side pumps the oxygen rich blood to the rest of the body and cells absorb the oxygen and load it with carbon dioxide when it returns the heart

Digestive System

Breaks down food into small molecules that can be used by the cells of the body

Four stages and 2 ways of digestion

Ingestion, Digestion, Absorption, Elimination

Chemical and Mechanical Digestion

Beginning of Digestive System/Mouth (digestive system)

With ingestion, food is brought into your mouth where saliva is released; digestion starts in the mouth where food is physically breaking down (mechanical digestion) and some chemical digestion happens as saliva has amylase which breaks down starch; your tongue will help shape the food into bolus

Pharynx/Epiglottis/Esophagus/Peristalsis (digestive system)

the bolus goes down through the pharynx and to the epiglottis (prevents food from going to trachea) where it goes down the esophagus where it pushes the food to the stomach; peristalsis which is muscle contraction helps move the bolus to the stomach

Stomach

mechanical digestion happens in which food is mixed with acid and enzymes to form chyme

Small Intestine

the main area of chemical digestion and most nutrient absorption takes place as it gets absorbed into the blood; peristalsis moves the chyme throughout the small intestine

Villi

Finger like structures, “folded”, absorption happens here where nutrients can get absorbed into the blood by the villi increase surface area to allow nutrients to get absorbed into the capillaries which is then transported to the blood

Large Intestine/Elimination

Absorbs water, substances that were not absorbed will be turned into waste that would be exited out of the body through elimination

Gallbladder/Liver/Pancreas (digestive system accessory organs)

Pancreas: releases digestive enzymes and bicarbonate into small intestine

Liver: produces bile and helps detoxify harmful chemicals in the body

Gallbladder: stores bile until needed for digestion

Thermoregulation

adjusting the rate of heat exchange

Negative feedback

Vasodilation (circulatory): blood vessels expand to release more heat

Sweating (skin): cooling by evaporative heat loss

Vasoconstriction (circulatory): blood vessels tighten to conserve heat

Shivering (muscles)

part of nervous system

Layers of skin (integumentary system)

epidermis: protection from bacteria, virus from entering our body (outer layer)

Dermis: blood (when blood is cold, blood vessel will contract when blood is hot, blood vessel will dilate), sweat glands, hair follicles, nerves

Endocrine System

A series of glands that release hormones to help control organs and maintain homeostasis; long distance chemical communication through the blood

Slower and last longer compared to the nervous system

Glands secrete or release hormones that bind to target cells

Pancreas (endocrine)

regulates blood glucose; releases insulin when blood glucose is high and releases glucagon when blood glucose is low

Insulin and Glucagon (endocrine)

Insulin: released when blood glucose is high, lowers blood glucose levels and helps glucose enter cells

Glucagon: Released when blood glucose is low, raises blood glucose levels and tells liver to break down glycogen into glucose

Hypothalamus

The link between the nervous system and the endocrine system, maintains homeostasis (hunger, thirst, body temp) can send signals to other glands to release hormones

Excretory System

responsible for eliminating metabolic waste

Skin: excretes water, salts, and a small amount of urea

Lung: excretes carbon dioxide (from cellular respiration)

Liver: converts dangerous nitrogenous wastes into urea

Kidneys: filters out wastes from the blood using nephros, reabsorbs useful substances, excretes salt water and urea; renal artery: blood into kidneys, renal vein: blood into kidneys

Ureters: transport urine from kidneys to bladder

Urinary bladder: stores urine

Urethra: releases and carries urine from bladder to out of the body

Nervous System

Collects information form the external and internal environment, process it, then responds. Messages are carried by an impulse. An impulse is an electrical signal that is fast and carries the message from the neuron to another cell.

Parts of the brain

Cerebrum: main part; responsible for reasoning, thinking, movement, speaking

Cerebellum: coordination and balance

Brain stem (medulla): autonomic; breathing, digestion, heart rate

Central NS and Peripheral NS

CNS: Includes brain and spinal cord, Process the information and sends a response

PNS: Sends the information to and from the CNS

Somatic NS and Autonomic NS

Sympathetic NS and Parasympathetic NS

Respiratory System

responsible for the process of gas exchange with the environment