Human physiology

ingestion

eating

digestion

This process of breaking down food into molecular particles of usable size and content.

absorption

taking up monomers, vitamins, minerals, water

egestion

(also called elimination) getting rid of waste products that weren’t absorbable

chemical digestion

breaking down the food by saliva, pancreatic juice (enzymes, NaOH), bile, gastric juice (enzymes, HCl).

mechanical digestion

Breaking down food by teeth and muscle movement (peristalsis)

enzymes

proteins that act as biological catalysts by accelerating chemical reactions

amylase

breaks down starch into maltose and later glucose

pepsin (a protease)

breaks down protein into polypeptides and dipeptide

lipase

breaks down triglycerides into glycerol and 3 fatty acids

alimentary canal

esophagus, stomach, small and large intestine

peristalsis

the muscle movement in the esophagus

bolus

a ball-like mixture of food and saliva that forms in the mouth during the process of chewing

salivary glands

produces saliva

Esophagus

transports the food from the mouth to the stomach

Gastric juice (mucus, HCI, pepsin)

break down food and mixes it into chyme.

optimum pH

the pH level that makes the enzymes the most effective

small intestine

break down food, absorb nutrients needed for the body, and transports other components to the large intestine

Doudenum

Chemical digestion with the help of pancreatic juice and bile from the liver.

pancreas

Chemical digestion by pancreatic juice (containing amylase, protease and lipase) Alkaline ions →increase the pH to 7

pancreatic juice

contains amylase, protease and lipase

Sodium, hydrogen carbonate (bicarbonate ions)

regulating pH

gall bladder

Chemical digestion by bile, which is stored by the gall bladder.

bile

Bile is emulsifying lipids, meaning that it splits bigger fat drops into smaller ones.

Emulsification

Emulsifying lipids, meaning that it splits bigger fat drops into smaller ones.

villus

Small extension of the wall of the small intestine to increase surface area.

villi function

Increase surface area to increase absorption.

large intestine

Absorption of water (osmosis), minerals and vitamins. Bacteria live their and they help with the production of vitamin K.

Feces

what is eliminated from the body after absorption.

assimilation

the process of absorption of vitamins, minerals, and other chemicals from food as part of the nutrition of an organism.

atrium-atria

Atria are smaller and have thinner walls compared to the ventricles.

ventricle

The left ventricle has the largest muscular wall.

valves

• Open and close due to changes in pressure

• Opens only in one direction

• Make sure that the blood doesnt backflow

atrioventricular valves

5. Atrioventricular valves (AV valves) - between atria and ventricles

semi lunar valves

5. Semi lunar valves (SL valves) - between ventricles and the big arteries

aorta

Ventrical systole - ventricles contract (both left and right side), the blood goes from the ventricles to the aorta and the pulmonary artery through the SL-valves. SL-valves close (sounds DUB) due to the pressure being higher in the aorta and pulmonary artery compared to the ventricles.

vena cava (superior/inferior)

Your inferior vena cava, your body's largest vein, carries oxygen-depleted blood back to your heart from the lower part of your body (below your diaphragm). Your superior vena cava, your second biggest vein, brings oxygen-poor blood from your upper body to your heart.

pulmonary artery

ventricles contract (both left and right side), the blood goes from the ventricles to the aorta and the pulmonary artery through the SL-valves. SL-valves close (sounds DUB) due to the pressure being higher in the aorta and pulmonary artery compared to the ventricles.

pulmonary vein

The lung veins sometimes referred to as the pulmonary veins, are blood vessels that transfer freshly oxygenated blood from the lungs to the left atria of the heart.

double circulatory system

Two circuits

1. Pulomonary (lungs) circulation

   From the right side of the heart to the lungs and back again. In the lungs, the blood becomes oxygenated. O2 diffuses (by simple diffusion) from a high concentration in the alveoli (lung sacks) to a low concentration in the blood, while CO2 diffuses from a high concentration in the blood to a low concentration in the alveoli.

2. Systemic circulation

   From the left side of the heart to the body and back again on the right side. During the way through the body the blood becomes deoxygenated. O2 diffuses from a high concentration in the blood to a low concentration in the cells O2 is used in cell respiration and the waste product is CO2. CO2 diffuses into the blood with its concentration gradient.

oxygenated blood

carries oxygen, has a larger concentration of O2 than CO2

deoxygenated blood

carries a larger concentration of CO2 than o2

coronary arteries

Coronary arteries supply blood to the heart muscle. Like all other tissues in the body, the heart muscle needs oxygen-rich blood to function. Also, oxygen-depleted blood must be carried away. The coronary arteries wrap around the outside of the heart.

heart beat

Control of a heart beat

• The heart muscle is myogenic = the signals for contracting the muscle arise in the heart itself (not needing any impulse from the nervous system).

• The heart beat is controlled by specialized cells located in the atrial wall (right). These cells are called the SA-node (the hearts natural pacemaker).

• The SA-node starts the heart cycle about 60 times per minute. The electrical impulse spread to the atrial walls →contraction of the atria.

• The impulse travel further down to the AV-nod where the impulse is delayed →the ventricles are filled with blood.

• The impulses are further spread from the AV-node to the bundle of His and the Purkinje fibers in the ventricle walls (contraction of ventricles).

systole - diastole

Systole - the heart muscle contract (working phase)

• Push out the blood from the heart

• Atrial systole - atria (both left and right side) contract, the blood goes from atria to ventricles. AV-valves close (sounds LUB) due to the pressure being higher in the ventricles than in the atria.

• Ventrical systole - ventricles contract (both left and right side), the blood goes from the ventricles to the aorta and the pulmonary artery through the SL-valves. SL-valves close (sounds DUB) due to the pressure being higher in the aorta and pulmonary artery compared to the ventricles.

Pacemaker, SA-node, AV-node

• The heart beat is controlled by specialized cells located in the atrial wall (right). These cells are called the SA-node (the hearts natural pacemaker).

• The impulse travel further down to the AV-nod where the impulse is delayed →the ventricles are filled with blood.

artificial pacemaker

A pacemaker is a small, battery-powered device that prevents the heart from beating too slowly. You need surgery to get a pacemaker. The device is placed under the skin near the collarbone. A pacemaker also is called a cardiac pacing device.

blood vessels, structure and function

arteries: big, large musculary wall, transport blood from the heart; capillaries: small, here the gas and nutrient exchange takes place; veins: big, thin musculary wall, transport blood to the heart

arteries

arteries: big, large musculary wall, transport blood from the heart

veins

veins: big, thin musculary wall, transport blood to the heart

capillaries

small blood vessels only one cell thick, allows an efficient exchange of molecules. All amino acids and monosaccharides are transported into the capillaries, and then transported through the blood stream to all body cells.

blood

the red liquid that circulates in the arteries and veins of humans and other vertebrate animals, carrying oxygen to and carbon dioxide from the tissues of the body.

blood composition

plasma, red blood cells, white blood cells, and platelets

plasma

blood plasma: consists of H2O, nutrients, hormones, antibodies…

Erythrocytes

red blood cells (RBC), are the functional component of blood responsible for the transportation of gases and nutrients throughout the human body.

plateles

platelets: help with blood clotting

leukocytes

White blood cells, also called leukocytes, immune cells, or immunocytes,

hemoglobin

a red protein responsible for transporting oxygen in the blood of vertebrates. Its molecule comprises four subunits, each containing an iron atom bound to a haem group.

ECG

(electro cardiogram)

P - atria contract (SA-node/AV-node)

QRS - ventricles contract (AV-node/bundle of His/Purkinjefibers)

T - ventricles reset

ventilation

The process of air entering and exiting the lungs.

Inhalation = air enters

Exhalation = air exits

respiration

• Transports O2 to all cells for cell respiration.

• Remove CO2, which is a waste product from cell respiration (CO2 forms carbonic acid, which decreses pH, meaning its important to remove).

gas exchange

• To take in O2 and take out CO2.

• O2 is headed for cellular respiration (all cells)

• CO2 is a rest product of cellular respiration

• Location: the alveoli

trachea

1. 

brochus/ bronchi

Bronchioles

inhalation

Diaphragm contracts and moves the chest cavity downwards → Increase the lung volume.

External intercostal muscles contract and move the chest cavity outwards → increase the lung volume.

The gas pressure inside the lungs decreases and a pressure gradient is formed.

Air will move from a higher pressure in the atmosphere to a lower pressure inside of the lungs.

exhalation

Diaphragm relaxes and the chest cavity move upwards → decrease the lung volume.

Internal intercostal muscles contract and the chest cavity moves inwards → decrease the lung volume.

The gas pressure in the lungs Increases.

Air will move with its pressure gradient from the lungs to the atmosphere.

diaphragm

located between the chest cavity (thorax) and The abdominal cavity.

external intercostal muscles

External intercostal muscles contract and move the chest cavity outwards → increase the lung volume.

internal intercostal muscles

Internal intercostal muscles contract and the chest cavity moves inwards → decrease the lung volume.

thorax

• Diaphragm - located between the chest cavity (thorax) and The abdominal cavity.

alveolus/ alveoli

Alveoli (lung sacks, where gas exchange happens)

capillary

Capillaries are delicate blood vessels that exist throughout your body. They transport blood, nutrients and oxygen to cells in your organs and body systems. Capillaries are the smallest blood vessels in your vascular system.

red blood cell

red blood cells: transport O2

diffusion

1. From the right side of the heart to the lungs and back again. In the lungs, the blood becomes oxygenated. O2 diffuses (by simple diffusion) from a high concentration in the alveoli (lung sacks) to a low concentration in the blood, while CO2 diffuses from a high concentration in the blood to a low concentration in the alveoli.

tar, carbon monoxide, nicotine

Tar is the name for the resinous, combusted particulate matter made by the burning of tobacco and other plant material in the act of smoking.

In smoking, long term exposure to compounds found in the smoke (e.g., carbon monoxide and cyanide) are believed to be responsible for pulmonary damage and for loss of elasticity in the alveoli, leading to emphysema and chronic obstructive pulmonary disease (COPD).

Nicotine is a dangerous and highly addictive chemical. It can cause an increase in blood pressure, heart rate, flow of blood to the heart and a narrowing of the arteries (vessels that carry blood). Nicotine may also contribute to the hardening of the arterial walls, which in turn, may lead to a heart attack.

carcinogens

These chemicals damage our DNA, including parts of our DNA that protect us against cancer. Chemicals in cigarette smoke also make it harder for our cells to repair DNA damage. This means DNA damage can build up. It's the build-up of DNA damage in the same cell over time that leads to cancer.

chronic bronchitis

(cilia, epithelium, mucus, smokers cough, obstructed airways)

Emphysema

(Infection, phagocytes, elastin, elastase, decreased recoiling, brusted alveoli)

Lung cancer

Cancer is a disease in which cells in the body grow out of control. When cancer starts in the lungs, it is called lung cancer. Lung cancer begins in the lungs and may spread to lymph nodes or other organs in the body, such as the brain. Cancer from other organs also may spread to the lungs.

diastole

Diastole - the heart muscle relax (resting phase)

• Fill up the heart with blood

• Av- valve opens, so both the atria and ventricles can be filled with blood.