bio chap 7 - respiration in humans

Question 1

give 6 examples which respiration is used by living organisms for life processes

Answer 1

synthesis of new cytoplasm for growth and repair
synthesis of new protoplasm for growth and repair
active transport
muscular contractions such as heartbeats and respiratory movements
transmission of nerve impulses
cell division

Question 2

what is aerobic respiration

Answer 2

the release of energy by the breakdown of glucose in the presence of oxygen

Question 3

what is the word equation for aerobic respiration

Answer 3

glucose + oxygen -> carbon dioxide + water + energy

Question 4

what is the importance of aerobic respiration?

Answer 4

releases a large amt of energy
most animals, including humans, and green plants respire aerobically as they are active organisms that require a large amount of energy to survive

Question 5

what is anaerobic respiration

Answer 5

the release of energy by the breakdown of glucose in the absence of oxygen

Question 6

is anaerobic respiration less or more efficient than aerobic respiration?

Answer 6

less efficient in terms of energy yield

Question 7

what happens in muscle cells when there are vigorous muscular contractions?

Answer 7

muscle cells respire anaerobically at a higher rate. the person may start panting to remove carbon dioxide and take in oxygen at a faster rate. the heart may beat faster so that oxygen can be transported to the muscles at a faster rate

Question 8

what happens in muscle cells when vigorous activity continues?

Answer 8

muscular contractions are so vigorous that maximum aerobic respiration is unable to release energy fast enough to meet the high energy demand

muscles carry out anaerobic respiration to meet the high energy demand and lactic acid is formed in the process

Question 9

what is the word eqn for anaerobic respiration in muscle cells

Answer 9

glucose -> lactic acid

Question 10

what is the word eqn of anaerobic respiration in yeast during alcoholic fermentation?

Answer 10

glucose -> ethanol + carbon dioxide

Question 11

what is the importance of anaerobic respiration

Answer 11

the small amt of energy is released in anaerobic respiration paired with the large amt of energy released in aerobic respiration keeps muscles contracting

Question 12

what is oxygen debt

Answer 12

the amount of oxygen needed to remove lactic acid

Question 13

how is oxygen debt removed after a race/ vigorous activity

Answer 13

the continuation of fast heart rate results in continued and fast transport of lactic acid from the muscles to the liver and oxygen from the lungs to the liver

the continuation of deeper and fast breathing ensures the continued and fast intake of oxygen by the lungs
This provides a sufficient amount of oxygen to remove lactic acid from blood
once lactic acid is removed, oxygen debt is repaid

Question 14

How do we study respiration?

Answer 14

The process of respiration in humans is the same as in other organisms
Plants, animals and microorganisms are often used in experiments to investigate respiration

Question 15

How do we show that an organism respires aerobically?

Answer 15

Some energy released from aerobic respiration is given off as heat. If an organism consumes oxygen and gives off carbon dioxide and heat, it respires aerobically

Question 16

how do we show that a substance respires anaerobically?

Answer 16

anaerobic respiration is difficult to detect and does not require consumption of oxygen and may not produce carbon dioxide

however in microorganisms such as yeast do produce and give off carbon dioxide when they respire anaerobically

if substance gives off carbon dioxide in the absence of oxygen, it respires anaerobically

Question 17

what is the difference between the type of process of respiration and photosynthesis

Answer 17

respiration is a catabolic reaction which breakd down complex molecules into simpler ones releasing energy stored in glucose

photosynthesis is an anabolic process as it builds complex molecules from simpler ones. it converts light energy stored in glucose

Question 18

what is the difference between the sites of respiration and photosynthesis

Answer 18

respiration occurs in the mitochondria for all living cells and does not require sunlight. it uses glucose and oxygen to produce energy

photosynthesis occurs in chloroplasts of green plants and some bacteria and requires sunlight, carbon dioxide and water

Question 19

what is the difference between the end products of respiration anf photosynthesis

Answer 19

the end products of respiration are carbon dioxide and water

the end products of photosynthesis are glucose and oxygen

Question 20

what is the difference between the reactions of respiration and photosynthesis?

Answer 20

respiration releases energy by breaking down glucose which makes it an exothermic reaction

photosynthesis stores energy by converting light energy into chemical energy in the form of glucose which makes it an endothermic reaction

Question 21

what is the difference between the importance of respiration and photosynthesis?

Answer 21

respiration is essential for releasing stored energy from glucose, fueling cellular processes and mantaining life functions in organisms

photosynthesis is crucial for provisioning oxygen and organic compounds for ecosystem serving the primary source of events and nutrients

Question 22

how does gas exchange occur in organisms that have a high surface area to volume ratio?

Answer 22

oxygen and carbon dioxide exchanged efficiently between the organism and the surroundings by diffusion through the cell membrane

Question 23

how does gas exchange occur in organisms that have a small surface area to volume ratio?

Answer 23

the external surfaces are thickened for protection to prevent water loss and are unsuitable for gas exchange
these animals have special organs such as lungs and gills for gas exchange
these organs have an enlarged surface area and thin coverings which allows more oxygen absorbed and more carbon dioxide removed from the body per unit time. this is because there is a shorter diffusion distance and higher surface area to volume ratio

Question 24

what is the process of gas exchange in the nose?

Answer 24

air enters the body through the two external nostrils
the nostrils lead into 2 nasal passages lined with moist mucus membrane

Question 25

what is the adaptation of the nose for gas exchange?

Answer 25

as air passes through the nasal passages, it is warmed and moistened

dust and foreign particles are trapped by hairs in the nostrils and mucus on the mucous membrane

harmful chemicals may be detected by small sensory fells in the mucous membrane

Question 26

what is the process of gas exchange from the nose to the trachea?

Answer 26

air in the nasal passage enters the pharynx
from the pharynx, air passes into the larynx then into the traches through an opening

Question 27

explain the structure of the trachea

Answer 27

it is supported by c-shaped rings of cartillage which keeps the lumen of the trachea open
membrane next to the lumen is the epithelium which consists of 2 types if cells, gland cells and cilitated cells

Question 28

what is the function of the gland cell

Answer 28

secrete mucus to trap dust like particles and bacteria

Question 29

what is the function of ciliated cell

Answer 29

have hair like structjres called cilia on their surfaces that sweep up dust-trapped mucus up the trachea

Question 30

what is the process of gas exchange in the bronchi and bronchioles?

Answer 30

trachea divides into 2 tubes, the bronchi
each bronchus carries air into the lung
each bronchus rise repeatedly, giving rise to numerous bronchioles that end in a cluster of alveoli

Question 31

how is the concentration gradient for oxygen and carbon dioxide set up and mantained?

Answer 31

it is set up between blood and alveolar air
mantained by a continuous flow of blood through the capillaries
and continuous breathing ensuring air in the lungs are constantly refreshed

Question 32

what is ths process of gas exchange in the alveoli

Answer 32

oxygen dissolves into the thin film of moisture on the wall of the alveolus

dissolved oxygen diffuses through the walls of the alveolus and the wall of the blood capillary into the red blood cells

oxygen combines with haemoglobin to form oxyhaemoglobin

carbon dioxide diffuses from blood into alveolar air

Question 33

what are the adaptations of the alveolus

Answer 33

numerous alveoli in lungs provide a large surface area for gas exchange

wall of alveolus is one cell thick which provides a short diffusion distance for gases increasing the rate if diffusion

thin film of moisture covers the inner wall of the alveolus which allows oxygen to dissolve in it

walls of the alveoli are richly supplied with blood capillaries as the flood of blood mantains the concentration gradient of gases

Question 34

how is oxygen transported around the body?

Answer 34

in the lungs with a high conc of oxygen, oxygen combines with haemoglobin to form oxyhaemoglobin

in the tissues with a low conc of oxygen, oxyhaemoglobin releases its oxygen to respiring cells

Question 35

how does the composition of inspired air differ from expired air

Answer 35

in expired air, some water evaporates from the surface if the alveoli which causes expired air to be saturated with water vapour

in inspired air, in the lungs oxygen is absorbed into the bloodstream and carbon dioxide is released from the blood
this causes air breathed out to have a lower oxygen conc and higher carbon dioxide than the air breathed in

Question 36

what are the harmful effects of nicotine?

Answer 36

increases heart rate and blood pressure
increase the risk of blood clots in arteries which increases the risk of coronary heart diseases
increases the risk of narrowed arteries

Question 37

what is the effect of narrow arteries on pregnant mothers?

Answer 37

narrow arteries decrease the amt of food substances reaching the fetus affecting fetal development

Question 38

what are the effects that carbon monoxide has on human health?

Answer 38

decreases the ability of blood to transport oxygen, because carbon monoxide binds permanently with haemoglobin

increases the risk of chd

Question 39

whats the effect of a decreased ability of blood to transport oxygen

Answer 39

affects fetal development in a pregnant mother as decreases oxygen reaches the fetus

Question 40

what is the effects on tar on human health?

Answer 40

increasing the risk of cancer in the lungs as tar causes uncontrolled cell division

increases the risk of chronic bronchitis and emphysema. tar paralyses the cilia lining the air passages causing dust particles trapped in mucus lining to not be removed

Question 41

what are the three diseases caused bu tobacco smoke?

Answer 41

chronic bronchitis
emphysema
lung cancer

Question 42

what causea chronic bronchitis?

Answer 42

epithelium lining of air passages becoming inflamed
increased mucus secreted by epithelium
cilia on the epithelium are paralysed and mucus and dust particles cannot be removed

this causes air passages to be blocked, causing breathinh difficulties leading to persistent coughing occurs to clear air passages, increasing the risk of lung infection

Question 43

what happens during emphysema and what is the cause?

Answer 43

persistent and violent coughing may lead to emphysema
partition of walls between alveoli break down due to persistent and violent coughing which decreases the surface area for gaseous exchange
lungs lose elasticity and become inflated with air
breathing becomes difficult

Question 44

what is the disease where both chronic bronchitis and emphysema is experienced?

Answer 44

chronic obstructive lung disease

Question 45

what is cancer?

Answer 45

uncontrolled cell division producing lumps of tissues

Question 46

what is the health risk of smoking?

Answer 46

increases the risk of cancers of
lungs
mouth
throat
pancreas
kidneys
urinary bladder