biological processes

features of the lungs

alveoli

bunches of tiny air sacs inside the lungs

breathing

the process in which air is moved in and out of the lungs

air

A mix of different gases - 78% nitrogen, 21% oxygen, 0.04% carbon dioxide, and the remainder is other gases.

what do body cells contain for cellular respiration

Body cells contain structures called mitochondria that use oxygen for cellular respiration

cellular respiration in mitochondria

uses oxygen and sugar from food as fuel to provide energy for life processes

process of inhalation

1.

Intercostal muscles contract, pulling the ribs outward
2.the diaphragm contracts and pulls down
3.As the volume and space in the lungs increases, the pressure drops
4.Air moves throughugh the nose, mouth, bronchus, and bronchioles, and gushes inside the lungs, filling the alveoli with fresh air.

process of exhalation

1.

The diaphragm muscles are relaxed and the diaphragm returns to its normal structure (upwards)

2.

The intercostal muscles relax, meaning that the ribs return back to their normal position (inwards)

3.

As the thoracic volume decreases causing the pressure to increase.

4.

Air in the alveoli is pushed out through the bronchioles, bronchus, and finally out by the nasal cavity.

gas exchange

carbon dioxide and oxygen switching, changing places

from where does oxygen diffuse into the blood?

particles of oxygen from the air sac diffuse into the blood

how is carbon dioxide brought to the lungs?

carbon dioxide is brought to the lungs by the blood

what occurs in gas exchange?

Carbon dioxide goes into the alveoli from the blood vessel, but oxygen goes from the alveoli to the blood vessel

what are the adaptations of the alveoli?

-they have moist thin walls
-they give the lungs a large surface area
-they have a lot of tiny blood vessels called capillaries

what does the heart do?

pumps blood around the body and the blood contains nutrients necessary for respiration: oxygen and glucose

heart structure

in which direction do arteries carry blood?

arteries carry blood AWAY from the heart

in which direction do veins carry blood?

veins carry blood INTO the heart

what vein carries OXYGENATED blood?

pulmonary vein carries OXYGENATED blood

what artery carries DEOXYGENATED blood?

pulmonary artery carries DEOXYGENATED blood

what are the first 5 steps of the flow of blood through the heart?

1. blood enters through the vena cava

2. it fills up the right atrium

3. tricuspid valve opens up and blood flows through to right ventricle

4. right ventricle fills upend muscles contract forcing blood up and through semilunar valve

5. blood leaves heart to lungs through pulmonary artery

what are the last 5 steps of the flow of blood through the heart?

6. blood enters heart through pulmonary vein

7. it fills up left atrium

8. bicuspid valve opens and blood flows through to left ventricle

9. left ventricle fills up and muscles contract forcing blood up through the semilunar valve

10. blood leaves heart through aorta

arteries

• carry blood AWAY from the heart

• carry blood under HIGH pressure

• thick MUSCULAR walls

veins

• carry blood to the heart under low pressure

• thin walls

• have valves and large lumen

capillaries

• one cell thick

• connect arteries and veins

• carry blood under very low pressure

red blood cell

carries oxygen around the body

white blood cell

engulf invading pathogens

plasma

fluid which carries other blood components

platelet

plays an important role in blood clotting

blood

blood is a tissue consisting of plasma, in which the red blood cells, white blood cells, and platelets are suspended.

red blood cells more details

• no nucleus

• biconcave shape

• contains haemoglobin - to which oxygen molecules attack

white blood cells more details

• responsible for immune responses

• fight infections

• engulfs invading pathogens and destroys them

respiration

the process that the body uses to release energy from digested food (glucose)

aerobic cellular respiration

glucose +oxygen —> carbon dioxide + water + energy

C6H12O6 + 6O2 —> 6O2 + 6H2O + ATP

atria

receive blood from the veins

ventricle

pump blood out into arteries

valves

prevent back flow of blood

pulmonary vein

carry blood to the heart

vena cava

carry blood to the heart

pulmonary arteries

carry blood away from the heart

left ventricle

pumps blood around the body

septum

prevents oxygenated and deoxygenated blood from mixing

anaerobic respiration

glucose —> lactic acid + energy

oxygen debt

lactic acid needs to been broken down by oxygen to allow muscles to return to normal during anaerobic respiration.

Diaphragm

Found underneath the ribcage

Intercostal muscles

Found in between the ribs