b8

what type of circulatory system do humans have

double circulatory system

pacemaker cells

in right atrium, sends electrical impulses that causes the walls of the heart to contract

order of blood flow

body-vena cava-RA-RV-valve-pulmonary artery- valve-lungs- pulmonary vein- LA-LV-valve- aorta- body

vein

carries blood to heart

artery

carries blood away from the heart

capillaries

exchanges nutrients and waste with the tissues

blood travel from atrium to ventricles process

atrium wall contracts and pushed blood into relaxed ventricle, ventricle wall contracts and pushed blood out of the heart, more blood flows into the relaxed atrium

arteries structure

high pressure blood, thick walls, thick muscle and elastic tissue, narrow lumen, high speed blood

veins structure

low pressure blood, thin walls, thin muscle and elastic tissue, wide lumen , valves to stop back flow , slow blood

capillaries structure

permeable walls, one cell thick walls, tiny lumen, low blood pressure

red blood cell function

carries oxygen to cells for cellular respiration

red blood cell adaptation

no nucleus- carries more oxygen, biconcave disc shape - absorb more oxygen, haemoglobin to bind to oxygen - has a red pigment

white blood cell function and structure

fight pathogens, has a nucleus

white blood cells 3 tasks

produce phagocytes to do phagocytosis ( engulf pathogens ) , produce lymphocytes which produce antibodies and antitoxins

platelet function and definition

cell fragments produced by giant cells in bone marrow, clot blood when bleeding

platelet 2 adaptations

secretes proteins that result in chemical reactions which clots the blood, proteins on their surface allow them to clump together and stick to block breaks in a vessel

plasma

carries all blood components

what does plasma carry

glucose, amino acids, hormones, carbon dioxide, urea

cardiac output

The volume of blood pumped through each ventricle per minute

Stroke volume

volume of blood pumped out of each ventricle each time the heart beats

Heart rate

number of beats per minute

cardiac output formula

cardiac output (ml/m) = stroke volume (ml) x heart rate (bpm)

aorta

carries oxygenated blood to the body

vena cava

carries deoxygenated blood from body to the heart

pulmonary artery

carries deoxygenated blood towards the lungs

pulmonary vein

carries oxygenated blood from lungs to heart

What is metabolism?

The combination of all chemical reactions in an organism 

What is the word equation for aerobic respiration? 

Glucose + oxygen ➔ carbon dioxide + water

What is glucose converted to during anaerobic respiration in animals?

lactic acid

word equation for anaerobic respiration in plants and fungi:

Glucose ➔ ethanol + carbon dioxide

what is the energy from respiration used for

chemical reactions to build larger molecules from smaller ones
muscle contraction to allow movement
Keeping warm and maintaining a constant temperature

anaerobic respiration reaction

glucose —> lactic acid

what is anaerobic respiration in yeast cells called

fermentation

when does the body anaerobically respire

anaerobic respiration takes place in muscles during vigorous exercise

difference between aerobic and anaerobic respiration

anaerobic respiration doesn’t fully break down glucose so releases less energy

what is oxygen debt

amount of oxygen needed to break down the built up lactic acid

investigating respiration experiment

• put hydrogen carbonate indicator in boiling tube

• place a layer of cotton wool

• add 10 seeds

• seal the tube with a bung

• use glass beads as a control

• observe after a few hours. Respiration produces CO2 which makes the solution more acidic

main components of blood

red blood cells, white blood cells, platelets, plasma

how does the structure of the artery help its function

thick muscular walls and elastic fibres can withstand high pressure blood and maintain the blood pressure. A narrow lumen maintains high pressure

how does the veins structure adapt it to its function

large lumen reduces resistance to blood flow under low pressure, valves to prevent back flow

how does the structure of the capillaries adapt it to its function

one cell thick walls and permeable walls for diffusion

label the heart 1-8

1. pulmonary artery

2. vena cava

3. right atrium

4. right ventricle

5. aorta

6. pulmonary vein

7. left atrium

8. left ventricle

diffusion

movement of particles from an area of high concentration to low concentration

why is transport important

organisms need to exchange substances by processes like osmosis , diffusion and active transport

why do multicellular organisms need transport systems

they have large distance from the cell membrane to inside the cell so diffusion wouldn’t be efficient enough for transporting substances

why do multicellular organisms need exchange surfaces

they have small surface area compared to their volumes so larger organisms need exchange surfaces within their transport system to carry out diffusion , osmosis and active transport at a sufficient rate

Rick’s law of diffusion

rate of diffusion is directly proportional to ( surface area x concentration gradient ) / thickness of the membrane

factors affecting rate of diffusion

diffusion distance, concentration gradient, temperature, surface area

how does increased surface area increase diffusion rate

more surfaces for the molecules to move and diffuse across

how does greater concentration gradient / difference in concentration on either side affect diffusion rate

substances diffuse faster id there’s larger difference in concentration . If there are more particles, they diffuse faster to try balance the concentration and spread out

how does temperature affect diffusion rate

molecules have more KE and faster movement across membrane

what is the purpose of the alveoli

gas exchange of oxygen and carbon dioxide

adaptations of alveoli

thin cell membrane, good blood supply, large surface area, ventilation, layer of moisture

what is the purpose of good blood supply for the alveoli

maintain steep concentration gradients of O2 and CO2 to allow easy gas exchange

what is the purpose of ventilation in the alveoli

creates a steep concentration gradient and mains high levels of oxygen and low levels of CO2 to increase diffusion rate

what does the layer of moisture do in the alveoli

dissolves gases helping them diffuse

what does the large surface area and thin membrane do in the alveoli

increase rate of diffusion

how do receptors on membrane act as an adaptation for wbc

detect pathogens

how does the nucleus/ribosomes act as an adaptation for wbc

make antibodies / antitoxins

how is flexible membrane an adaptation for wbc

to engulf pathogens

ficks law of diffusion

rate of diffusion is proportional to ( surface area x concentration gradient ) / diffusion distance

how can membrane characteristics affect rate of diffusion

thinner and more permeable membrane can increase diffusion rate

how might cell size affect diffusion rate

smaller cells and elongated / irregularly shaped cells increase diffusion due to their higher surface area

how is the small intestine adapted for absorbing dissolved food molecules

villli to increase surface area to volume ratio, good blood supply to maintain concentration gradient

features of efficient gas exchange surface

large surface area, thin membrane, large concentration gradient

what is the rate of diffusion inversely proportional to

membrane thickness

how can steeper concentration gradient increase diffusion

more random collisions against the membrane so faster diffusion

oxygen debt equation

lactic acid + oxygen —> carbon dioxide + water

what is the difference of glucose breakdown in aerobic and anaerobic respiration

in aerobic respiration there is complete breakdown of glucose but not in anaerobic

where does aerobic respiration happen

mitochondria

where does anaerobic respiration happen

cytoplasm

respiration

reacion in cells that releases energy through the breakdown of glucose in the presence of oxygen.

why does anaerobic respiration occur during intense excersise

the muscles require more energy but aerobic respiration is at its maximum rate and oxygen isn’t supplied fast enough

what 2 industrial processes make use of anaerobic respiration of yeast

bread making, beer making

compare the rate of respiration for germinating seeds and boiled/dead seeds

germinating seeds respire a lot and use energy for growth. boiled seeds have denatured enzymes so cant respire

why is respiration essential for living organisms

releases energy for metabolic processes

why is there more respiration in the roots than leaves

they have more mitochondria

how can anaerobic respiration harm yeast cells

it produces ethanol which can build up and kill yeast cells

what are 2 sources of error

random error, systematic error

what is an example of random error in the respiration experinent

room temperature increase

transport systems in animals

circulatory system

exchange surfaces in animals

lungs and alveoli . small intestine and villi

transport systems in plants

xylem and phloem

exchange surfaces in plants

roots and root hairs , leaves

difference in stroke volume between someone who doesnt excersise frequently and someone who does

person who doesnt excersise has lower stroke volume due to weaker ventricular muscles so his heart pumps less blood per heart beat, so he needs to have higher heart beat to have similar cardiac output and excersise at same intensity