Yr 10 Human bio

Atria

Chambers of the heart that receive blood from the body

• left atrium : upper chamber takes oxygenated blood

• right atrium: receives deoxygenated blood from the body

ventricle

Chambers of the heart that pump blood out of the heart 

• right ventricle pumps blood into the lungs

• left ventricle pumps blood into the aorta

valve

Structure of the heart that prevents the backflow of blood 

Artery

• Blood vessel that carries oxygenated blood away from the heart 

• have thick, muscular and elasticwalls to cope with high blood pressure

• they have small lumen

• blood pressure that increases as the ventricles contract and decrease as ventricles relax

vein

• Blood vessel that carries mostly deoxygenated blood towards the heart 

• thin walls that arent elastic or muscular

• have large lumen

• blood pressure is constant and relitively low

• most veins have values which prevent backflow of blood

capillary

• Microscopic blood vessel that delivers blood to the cells

• smaller arteries called arterioles are connected to small veins called venules by a network of microscopic blood vessels called cappilaries

• bring blood close to every cell where gas and nutrient exchange can take place

• walls are thin to make diffusion easier

systole

Period of contraction of the heart muscle

diastole

Period of relaxation/rest of the heart muscle, during which the heart fills with blood

red blood cell

• Cell responsible for transporting oxygen around the body 

• called erythrocytes

• no nucleus so it can carry more oxygen and haemoglobin

• haemoglobin (iron) carries/binds the oxygen

• biconcave disc shaped increases surface area and allows flexibility (fit through narrow cappilaries)

• live for 120 days

• madde in the red bone marrow

white blood cell

• Cell responsible for carrying out an immune response 

• also called leucocytes

• surround and engulf disease causing microorganisms such as bacteria through phagocytocis (cell easting)

• larger than RBC’s

• have a nucleus

• life span depends on health of the body - healthy lives a week - unhealthy - lives a few hours

platelet

• Cell fragment responsible for blood clotting 

• also called thrombocytes

• very small fragments of cells no nucleus

• cressent moon shape

• when a blood vessel is injured they clump together to form a blood clot so nutrients and cells dont escape into tissue

• formed in red bone marrow

• live 7 days

plasma

Fluid component of blood 

Antigen

• a protein that sits on the surface of a cell and serves as an identity marker

• they determine whether a cell is meant to be in your body

• determines blood type

• not present on the o blood type

• A - spiky

• B - curved

• AB- both

• 
  

antibody

• a set of proteins produced by white blood cells that destroy non self antigens

• A- produces B anitbodies -can only be given A or O blood type

• B- produces A antibodies - can only receive B or O blood

• AB- produces no antibodies (universal receiver)

• O -produces A and B antibodies - can only recieve O blood (universal donor)

cardiac musscle tissue

more than 1 of the same cell type grouped together to acheive same function

atrio-venticular valve

controls the flow of blood between the atrium and ventricle

semi lunar valve

controls blood flow as blood leaves the heart

aorta

largest blood vessel in the body, takes oxygenated blood to all the cells

superior and inferior vena cava

bring deoxygenated blood from all the cells to the heart
superior- comes from the top

inferior- comes from the bottom

plumerary artery

takes deoxygenated blood to the lungs

septum

divides the heart into left and right

cardiac muscles

contracts and relaxes continuously, never gets tired

heart

organ that pumps blood through the body

the cardiac cycle

a sequence of events that occurs in one complete beat of the heart. (0.8sec)

2 phases

• systole: heart muscle contracts (pumps blood)

• diastole: heart muscle relaxes (filling with blood)

stages of the cardiac cycle

Atriol systole: atria contract - blood goes to ventricles

ventricular systole: ventricles contract forcing blood to major arteries (aorta or pulminary)

diastole: all chambers are relaxed and filling with blood

timeline of the cardiac cycle

. atria: systole (.1) diastole (.1-.4) diastole (.4-.8)

ventricles: diastole (.1) systole (.1-.4) diastole (.4-.8)

why is ventricle systole larger

Because they have to pump futher to places around the lungs and body

Blood pressure

• measured with a sphygomoanometer

• measures the pressure of the arteries as blood is pumped through the body

• recorded as 2 numbers like 120/80

• large indicates the pressure in the arteries as it squeeses out blood - systolic blood pressure

• lower indicates pressure as blood leaves the body - diastolic blood pressure

layers in blood vessels

Artery. veins

outer layer. outer layer

musclue layer. muscle layer

elastic layer. valve layer

inner layer inner layer

major arteries

• femoral - legs

• subclovian - sub clavical - returns lympth from cells to the heart

• corrotid - head and neck

• messentric - stomach and intestines

• renal - kideys

• brachial - arms

• pluminary - lungs

• coronary - heart

major veins

• jugular - head

• brachial - arms

• lungs - plumonary

• coronary - heart

• renal - kidneys

• femoral - legs

blood

carrys oxygen and nutrients to cells and removes waste and C02

4-5 L in a female

6L in a male

Components of blood

1. red blood cells - 45% (formed component (solid))

2. white blood cells - <1% (Formed components (solid))

3. platelets - <1% (formed components (solid))

4. plasma - 55% liquid, contains everything the body needs

plasma

• pale yellow

• carries formed elements

• contains hormones, glucose, enzymes, and waste products like CO2, O2, NA+ - dissolved in the plasma

breathing

movement of air in and out of the lungs

respiration

• the chemical process that occurs in cells converting oxygen into usable energy for cells. 

• Glucose + oxygen -> CO2 + water + energy

nose/nasal cavity (PoA)

• Filters, mositens and warms the air

• Smell receptors stimulated by substances in air

• Resonating chamber that enhances sounds produced in speech

• Hair + mucus trap foreign particles

Pharynx (PoA)

• Throat

• Air goes through pharynx to larynx from nasal cavity

• Used to pass food from the mouth to esophagus

larynx (PoA)

• voice box

• Allows for speech - vocal cords vibrate - sound is produced

trachea (PoA)

• Long tube lined with c shaped rings to give flexibility and support called cillia

• Lined with a mucus membrane to trap solid particles

bronchi (PoA)

• One left one right

• Singular - bronchus

• Contain cartilage rings and cilliated mucus membranes

bronchioles (PoA)

• Fine tues going to alveoli

• Too thin for cartilage and cillia

• Divides into further branches that are smaller

alveoli (PoA)

• Tiny sacks of air found in clusters

• Thin walls

• Surrounded by capillaries 

• Location of gas exchange

Gas exhange

• Process of exhnaging O2 and CO2. Occurs at the surface of alveloi and again at the cells

• Gasses move via diffusion -> the movement of molecules from high to low concentration until they are eventually distributed

• Occurs across semi-permobile membrane

process

• Air rich in CO2 enters lungs

• Blood capilary surrounding alveoli is deoxygenated (CO2)

• O2 molecules move from inside the alveoli into the capillary around it, to go to the heart to be pumped to the cells

• CO2 molecules move from the blood cappilary int the alveoli to be exhaled

Structures that aid the purpose of alveoli

1. Covered in capillaries - blood is as close to the air as possible to aid diffusion

2. Walls are 1 cell thick - gas doesnt have to travel far through thick membranes

3. Surface is covered in moisture - moist particles diffuse easier and so that the gas has a medium to travel into the air sack through

4. The lungs are deep in the chest - reduces the amount of water evaporation

5. Millions of alveoli - increase of surface area - > increases efficiency of diddusion