RESPIRATION

By: Avinash Thappa Central University of Jammu

Contents

1. Definition2. Types of respiration a. Aerobic respiration b. Anaerobic respiration4. Respiration in Plants.5. Respiration in Animals6. Human respiratory system

Definition

The process of releasing energy from food is called respiration.

OrIt is the process of oxidation of

respiratory substrate (mainly glucose) in the cells resulting in the release of carbon dioxide, water and energy.

Lightenergy

ECOSYSTEM

Photosynthesis in chloroplasts

CO2 + H2O Cellular

respirationin mitochondria

Organicmolecule

s

+ O2

ATP powers most cellular work

Heatenergy

ATP

Mitochondrion

Substrate-levelphosphorylatio

n

ATP

Cytosol

Glucose Pyruvate

Glycolysis

Electronscarried

via NADH

Substrate-levelphosphorylatio

n

ATP

Electrons carried

via NADH andFADH2

Oxidativephosphorylatio

n

ATP

Citricacidcycle

Oxidativephosphorylation

:electron transport

andchemiosmosis

Burning of Food A demonstration of energy released

from food

Burning

energywater

carbon dioxide

oxyge

n

food

(sugar)

food(sugar) +

oxygencarbon dioxide + water + energy (heat

+ light)

Breathing: It is the process by which organisms obtain oxygen from the air and release carbon dioxide is called breathing. It is physical process and involves movement of muscles and skeleton in order to increase the gaseous exchange.

Cellular respiration: It takes place inside the living cells where mitochondria is involved for the break down (oxidation) of simple food molecules(mainly glucose) and Carbon dioxide and energy is released in the form of ATP molecules.

Types of cellular respiration 1. Aerobic respiration: 2. Anaerobic respiration:

Aerobic Respiration: •Takes place in presence of oxygen

reactions are catalyzed by enzymes

main food substance which oxidized in

cells is glucose

C6H12O

6

+ 6O2

enzymes

6CO2 + 6H2O

+ energy as it takes place in all living cells, it is

called cellular respiration which is used

to produce energy for cells to use

Comparison of Burning and Respiration

Similarities

- both involve oxidative processes

- both require the use of oxygen and food and they produce the same products of carbon dioxide and water

- both reactions release energy

Differences

Burning Respiration

takes place in air or oxygen

takes place in cells

a single-step process

a series of chemical reactionsno enzymes

involvedcontrolled by

enzymes

Burning Respiration

Differences

energy release is

vigorous and not

under control

energy release is

slower and under

control energy is released

in form of heat and

light (a flame can

result)

energy is released

in form of heat and

an energy-rich

compound

ATP energy is mainly released as heat

and ATP during respiration in cells

however, during respiration, some

ATP should be consumed first before

other ATP can be formed

the ATP consumed is used to form

other ATP from ADP and phosphate

groups

ADP + energy (from

breakdown of glucose)

+

phosph

ate

ATP

ATP is a high-energy compound while

ADP is a low-energy one

ATP can only store energy for a short

period

ATP is made inside organelles,

mitochondria, which is scattered in

the cytoplasm of a cell

Anaerobic Respirationrespiration in human is mainly

aerobic respiration as oxygen is

essential

when oxygen is not needed during

respiration, it is called anaerobic

respiration

yeast and muscle cells are examples

which they can respire anaerobically

for a short time

Alcoholic Fermentation without oxygen, yeast cells respire as

follows:C6H12O

6

+ energy+ 2C2H5OH

(ethanol)

2CO2

enzymes

amount of energy released

anaerobically is smaller when

compared with the aerobic method

anaerobic respiration

aerobic respiration

amount of energy

released

large small

oxidation of glucose completely partly

place of occurrence

mitochondria cytoplasm

Industrial Use of Yeast Fermentation alcohol produced is used for:

brewing beer

making wine

carbon dioxide released is used

for:

baking bread

Lactic Acid Fermentation

extra oxygen is required for undertaking

sternuous exercise

people cannot supply enough oxygen

to muscles even they breathe faster

and deeper

lactic acid will cause muscle fatigue and

muscle cramps if they are allowed to

accumulate

C6H12O6 2C3H6O3 + energy

enzymes

muscle need to produce energy

anaerobically by breaking down

glucose into lactic acid

a large amount of oxygen is needed to

break down the accumulated lactic acid

into carbon dioxide and water or turn to

glycogen in liver for storage so we pant

after doing exercise the amount of oxygen required to get

rid of lactic acid is called oxygen debt

Comparison of Aerobic and Anaerobic Respiration

Similarity

Sugar is broken down to release

energy

ATP is made

Both are controlled by enzymes

Differencesaerobic

respirationanaerobic respiration

complete oxidation

incomplete oxidation

oxidation of sugar

essentialoxygen

requirement

nil

energy released

large amount

small amount

aerobic respiration

anaerobic respiration

in most living cells

in lower organisms (e.g.

bacteria and yeast) and vertebrate muscles

occurrence

inorganic: CO2 and

H2O

end products

organic: ethanol or lactic acid

Differences between Respiration and Photosynthesisaerobic

respirationphotosynthe

sis

energy is released

energy (light) is absorbed

produces carbon dioxide

and water

requires carbon dioxide and

water

an oxidative process

a reductive process

aerobic respiration

photosynthesis

occurs in all living cells at all times

occurs in green plants only when light is available

a breaking down process

a synthetic process

occurs in mitochondria

occurs in chloroplast

s

Respiration in Plants:

•Diffusion•Day time : oxygen release•Night time: C02 release

Respiratory Organs

Identify each type of respiratory adaptation, and relate to lifestyle.

Compare (if applicable) ventilation, gas exchange at the respiratory organ, transport of gases, and gas exchange at the tissues.

Tracheal System in Insects

Each cell has a nearly direct meansof gas exchange via the tracheal system (2-4 spiracles on the thorax, 6-8 on abdomen).

What is the advantage of such a system for a small, fast animal?Do insects have respiratory pigments in their hemolymph? Significance?

p. 984

(May serve as storage reserve)

Challenges of Gas Exchange related to

EnvironmentAir vs. Water: 20X more oxygen in air than in water

(at the same temp.) Diffusion of gas molecules is more

rapid in air Air is less viscous than water

ventilation (air) requires 1/10 the energy of water breathing

Gill Structure in Fish

p. 983

If fish gills are so efficient at gas exchange, why can’t most fish survive out of water?

Mechanics of Respiration:positive pressure breathing

Do amphibians have completely separate pulmonary and systemic circulatory systems?

What other organ(s) may be used in respiration?

Ventilation in Birds

Compare the size and complexity of the respiratory system in birds and amphibians (previous slide), and explain any differences.Compare the direction of airflow in birds and mammals. What does this imply regarding the pressure gradients at the transport epithelium?

p. 987

Mammalian Respiratory System

p. 985

Mechanics of Respiration:negative pressure

breathing

How do the serous membranes that cover the surfaces of the lungs and line the thoracic cavity facilitate breathing?

p. 986

Respiratory System

Function: to provide oxygen gas need for cellular respiration and remove carbon dioxide from the body

Invertebrate Organs: gills and trachae

Main Vertebrate Organs: Nose, mouth, pharynx, larynx,

trachea, bronchi, bronchioles, lungs, gills, diaphragm

Respiration in animals

Whether they live in water or on land, all animals must respire. To respire means to take in oxygen and give

off carbon dioxide. Some animals rely of simple diffusion

through their skin to respire. While others… Have developed large complex organ

systems for respiration.

Invertebrate respiration

Invertebrate respiratory organs have large surface areas Are in contact with air or water If require diffusion they must be moist.

Aquatic invertebrates

Aquatic animals have naturally moist respiratory surfaces, and some respire through diffusion through their skin. Example: jellyfish and anemones

Some larger aquatic animals like worms and annelids exchange oxygen and carbon dioxide through gills. Gills are organs that have lots of blood

vessels that bring blood close to the surface for gas exchange.

Terrestrial Invertebrates

Terrestrial invertebrates have respiratory surfaces covered with water or mucus. (This reduces water loss)

There are many different respiratory specialized organs in terrestrial invertebrates. Spiders use parallel book lungs Insects use openings called spiracles where air

enters the body and passes through a network of tracheal tubes for gas exchange

Snails have a mantel cavity that is lined with moist tissue and an extensive surface area of blood vessels.

How does respiration in aquatic invertebrates differ from that in terrestrial invertebrates?

Section 29-2

Mollusk

Insect

Spider

Gill

Siphons

Movement of water

Booklung

Airflow

Trachealtubes

Spiracles

Figure 29–9 Invertebrate Respiratory Systems

Vertebrate respiratory systems

Chordates have one of two basic structures for respiration: Gills – for aquatic chordates

Example: tunicates, fish and amphibians Lungs - for terrestrial chordates

Examples: adult amphibians, reptiles, birds, and mammals

Aquatic Gills

Water flows through the mouth then over the gills where oxygen is removed

Carbon dioxide and water are then pumped out through the operculum

Vertebrate lungs

As you move from amphibians to mammals the surface area of the lungs increases Insures a greater amount of gas exchange

(or a two way flow of air). Birds, by contrast have lungs and air

sacs which have only a one-way flow of air. This allows for them to have constant

contact with fresh air. This adaptation enables them to fly at high

altitudes where there is less oxygen.

Section 33-3

Salamander Lizard PigeonPrimate

Nostrils, mouth, and throatTracheaLungAir sac

Figure 33–10: Vertebrate Lungs

Section 37-3

Figure 37-13 The Respiratory System

The Human Respiratory System

Section 37-3

Flowchart

Oxygen and carbon dioxide exchange at

alveoli

Oxygen-richair from

environment

Bronchioles

Nasalcavities Pharynx Trachea Bronchi

BronchiolesAlveoli

PharynxNasal

cavities

Carbon dioxide-rich

air to the environment

Bronchi

Trachea

Movement of Oxygen and Carbon Dioxide In and Out of the Respiratory System

BIG QUESTION

…WHY DO ANIMALS BREATHE?