Biology Chapter 2.2(Animals and Heart) Flashcards
(26 cards)
What is surface area to volume ratio?
The surface area to volume ratio is the surface area per unit volume of an object.
What is the relationship between SA:V ratio and diffusion?
The smaller the organism,the larger the SA:V ratio is so the diffusion distance needed is much smaller
The greater the organism,the smaller the SA:V ratio is meaning the greater distance needed for diffusion so it can’t always be used
How do organisms increase diffusion at exchange surfaces?
In humans,we have alveoli in our lungs which increase the surface area for diffusion.
.Inside the small intestine,there a small villi structure which further increases surface area
Why are transported systems needed?
Organisms require transport systems to carry certain materials to where they need to be.
Animals have the circulatory system which uses blood
.Plants have xylem and phloem tubes
What does our circulatory system contain?
Our circulatory system contains our heart,blood and blood vessels and it is a closed system
How does blood flow in the circulatory system?
Blood flows twice through the heart each circuit ,which is known as a double circulatory system.
How do levels of oxygen change in our blood?
Red blood is oxygenated blood and blue blood is deoxygenated blood.
Describe the purpose of the circulatory system?
Your heart pumps oxygenated blood to all your organs to be able to supply them with glucose and oxygens
.The waste product, CO2 is created
.It is then transported back into the bloodstream and pumped back through the heart as deoxygenated blood into the lungs to be exhaled
Name the 3 types of blood vessels that transport blood
Arteries,veins and capillaries
Describe the structure of an artery
.Thick outer wall
.Thick layer of muscle and elastic fibres
.small lumen
.smal lining
Describe the structure of a vein
.Fairly thin outer wall
.Thin layer of muscle and elastic fibres
.large lumen
.Smooth lining
Describe the structure of a capillary
.very small lumen which is sermi-permeable
.wall made of single layer cells
Describe the function of an artery
Arteries carry blood away from the heart under high pressure
Describe the function of a capillary
Capillaries link arteries and veins in tissues and organs and are near all the cells to allow easy diffusion
Describe the function of a vein
Veins transport blood back to the heart
Why is the arterial wall thick and muscular
To withstand blood of high pressure
Why is walls of the vein thin
Blood pressure is low when entering the capillaries so a thick wall is not needed
What tissue is the heart made of
It is made of cardiac muscle tissue
Describe the structure of the heart
The heart has 4 key chambers;2 smaller chambers on the top which are the atria and 2 larger chambers on the bottom which are the ventricles
Valves separate the 4 chambers
Describe the vessels within the heart
Vena cava-brings deoxygenated blood into the heart
pulmonary artery-deoxygenated blood to the lungs
aorta-carries oxygenated blood around the body
pulmonary vein-brings oxygenated blood from the lungs
Describe the path blood takes through the double circulatory system
.Deoxygenated blood enters the right atrium.it is the pumped through the right ventricle into the lungs where it collects oxygen
.The blood then enters the heart through the pulmonary vein,then through the left atrium then ventricle and out through aorta to deliver the oxygen to all the cells.
Describe the function/structure of red blood cells
small biconcave disc
.No nucleus
.Contain haemoglobin which carries oxygen
.They fit through the lumen of the capillaries cells to get the specific cells
Describe the function/structure of white blood cells
.Large cells with nucleus
.Make antibodies which is used to help engulf microbes
Describe the function/structure of plasma cells
plasma cells are made up of 90% water and lot of materials are transported by dissolving into the plasma .For example:
Digested soluble foods(amino acids and glucose)
.Waste products(CO2)
.Hormones and antibodies
