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Flashcards in cellular respiration and transport Deck (112)
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1
Q

active transport

definition

A

The transport of molecules against their concentration gradient from a region of low concentration to a region of high concentration.

2
Q

aerobic respiration

definition

A

Respiration that requires oxygen.

3
Q

aveoli

definition

A

Tiny air sacs in the lungs, where gas is exchanged during breathing.

4
Q

anaerobic

definition

A

Without oxygen.

5
Q

antibody

definition

A

A protein produced by the immune system in humans (and other animals) that attacks foreign organisms (antigens) that get into the body.

6
Q

aorta

definition

A

Main artery which carries oxygenated blood from the heart in mammals.

7
Q

arteries

definition

A

Blood vessels that carry blood away from the heart.

8
Q

atria

definition

A

Upper chambers of the heart which receive blood from veins (singular - atrium).

9
Q

blood plasma

definition

A

The liquid part of the blood containing useful things like glucose, amino acids, minerals, vitamins (nutrients) and hormones, as well as waste materials such as urea.

10
Q

bone marrow

definition

A

Soft tissue found inside bones that produces new blood cells.

11
Q

capillary

definition

A

Tiny blood vessels with walls one-cell thick where exchange of materials occurs.

12
Q

cardiac output

definition

A

The amount of blood pumped by the heart in one minute. Heart Rate x Stroke Volume = Cardiac Output.

13
Q

endothermic

definition

A

Reaction in which energy is taken in from the surroundings.

14
Q

haemoglobin

definition

A

The red protein found in red blood cells that transports oxygen round the body.

15
Q

immune system

definition

A

The body’s defence system against entry of any foreign body, including pathogens and agents such as pollen grains. The role of the immune system is to prevent disease.

16
Q

nerve impulses

definition

A

Electrical signals that travel along the nerve fibre from one end of the nerve cell to the other.

17
Q

oxidise

definition

A

Chemical substances are oxidised by the addition of oxygen, removal of hydrogen or the removal of electrons.

18
Q

oxygen debt

definition

A

The amount of extra oxygen required by the body for recovery after vigorous exercise.

19
Q

phagocytes

definition

A

Cells, such as white blood cells, that engulf and absorb waste material, harmful microorganisms, or other foreign bodies in the bloodstream and tissues.

20
Q

phagocytosis

definition

A

The process of the ingestion of bacteria or other material by phagocytes.

21
Q

phloem

definition

A

The tissue in plants that transports the products of photosynthesis, including sugars and amino acids.

22
Q

plasma

definition

A

Liquid, non-cellular part of the blood.

23
Q

pulmonary artery

definition

A

The artery which carries deoxygenated blood from the heart to the lungs.

24
Q

pulmonary circuit

definition

A

The part of the circulatory system that involves the right side of the heart, the lungs, and the blood vessels that connect them together.

25
Q

pulmonary vein

definition

A

One of the four veins that carries oxygenated blood to the heart from the lungs.

26
Q

respiratory substrate

definition

A

A substance broken down by respiration to release energy.

27
Q

respirometer

definition

A

A device used to measure how fast respiration happens in an animal

28
Q

stroke volume

definition

A

The volume of blood pumped from the heart with each beat.

29
Q

systemic circuit

definition

A

The part of the circulatory system that includes the left side of the heart, the rest of the body apart from the lungs, and the blood vessels that connect them together.

30
Q

tissue fluid

definition

A

Fluid which is derived from blood plasma that passes through the walls of capillaries.

31
Q

valve

definition

A

The structure in veins that prevents the backflow of blood.

32
Q

vein

definition

A

A blood vessel with valves that transports blood to the heart.

33
Q

vena cava

definition

A

One of the two veins that carries deoxygenated blood to the heart from the body systems.

34
Q

ventilation

definition

A

Breathing in and out.

35
Q

ventricle

definition

A

The lower chamber of the heart that receives blood from the atrium and pumps it into arteries.

36
Q

The composition of blood

What does blood do?

A

Blood transports materials and distributes heat around the body. It also helps to protect against disease.

37
Q

What is plasma

A

Plasma is a straw-coloured liquid that makes up just over half the volume of blood.
(55%)

38
Q

What is the 45% of blood that is not plasma made up of?

A
  • Red blood cells
  • Platelets
  • white blood cells
39
Q

What is the function of the blood component: plasma?

A

Transporting dissolved carbon dioxide, digested food molecules, urea and hormones; distributing heat

40
Q

What is the function of the blood component: red blood cells?

A

Transporting oxygen

41
Q

What is the function of the blood component: white blood cells?

A

Ingesting pathogens and producing antibodies

42
Q

What is the function of the blood component: platelets.

A

Involved in blood clotting

43
Q

what do red blood cells contain, and why?

A

Red blood cells (also called erythrocytes) transport the oxygen required for aerobic respiration in body cells.

44
Q

Red blood cells and oxygen

A

They must be able to absorb oxygen in the lungs, pass through narrow blood capillaries, and release this oxygen to respiring cells.

45
Q

Red blood cells have several adaptations that enable them to carry out the function of transporting oxygen:

A
  • They contain the proteinhaemoglobin, which gives them their red colour
  • They have no nucleus so they can contain more haemoglobin.
  • They are small and flexible so that they can fit through narrow blood capillaries.
  • They have a biconcave shape - they are the shape of a disc that is curved inwards on both sides - to maximise their surface area for oxygen absorption.
  • They are thin, so there is only a short distance for the oxygen to diffuse to reach the centre of the cell.
46
Q

oxyhaemoglobin

A

Haemoglobin can combine reversibly with oxygen. This is important - it means that it can combine with oxygen as blood passes through the lungs, and release the oxygen when it reaches the cells.

47
Q

Different types of white blood cells

A
  • phagocytes

- lymphocytes

48
Q

White blood cells

phagocytes

A

About 70 per cent of white blood cells are phagocytes. Phagocytes engulf and destroy unwanted microorganisms that enter the blood, by the process of phagocytosis.

49
Q

White blood cells

lymphocytes

A

Lymphocytes make up about 25 per cent of white blood cells. Lymphocytes produce soluble proteins called antibodies when a foreign body such as a microorganism enters the body.

50
Q

Antibodies neutralise pathogens in a number of ways:

A
  • they bind to pathogens and damage or destroy them
  • they coat pathogens, clumping them together so that they are easily ingested by phagocytes
  • they bind to the pathogens and release chemical signals to attract more phagocytes
51
Q

Both phagocytes and lymphocytes are part of what?

A

Both phagocytes and lymphocytes are part of the body’s immune system.

52
Q

Other than antibodies, lymphocytes may also release what?

A

Lymphocytes may also release antitoxins that stick to the toxins that the microorganism makes, which stops it damaging the body.

53
Q

Platelets

A

Platelets are cell fragments produced by giant cells in the bone marrow.

54
Q

Platelets stop bleeding in two main ways:

A
  • they have proteins on their surface that enable them to stick to breaks in a blood vessel and clump together
  • they secrete proteins that result in a series of chemical reactions that make blood clot, which plugs a wound
55
Q

What is blood transported in?

A

Blood is transported in arteries, veins and capillaries.

56
Q

How does blood travel to and from the heart?

A

Blood is pumped from the heart in the arteries. It is returned to the heart in the veins.

57
Q

Function of capillaries

A

The capillaries connect the two types of blood vessel (arteries and veins) and molecules are exchanged between the blood and the cells across their walls.

58
Q

Structure of arteries

A
  • lumen (narrow)
  • inner lining (endothelium)
  • muscle and elastic fibres
  • connective tissue
59
Q

Structure of veins

A
  • lumen (wide)
  • inner lining (endothelium)
  • muscle and elastic fibres
  • connective tissue
60
Q

Features of arteries

A
  • Always carry blood away from the heart
  • Carry oxygenated blood, except for the pulmonary artery
  • Carry blood under high pressure
  • Have thick muscular and elastic walls to pump and accommodate blood
  • A type of supporting tissue called connective tissue provides strength
  • The channel in the blood vessel that carries blood - the lumen - is narrow
61
Q

features of veins

A
  • Always carry blood to the heart
  • Always carry blood to the heart
  • Carry blood under low or negative pressure
  • Have thin walls - have less muscular tissue than arteries
  • Have less connective tissue than arteries
  • Have a wide lumen
62
Q

Diffusion

capillaries

A

The walls of capillaries are just one cell thick. Capillaries therefore allow the exchange of molecules between the blood and the body’s cells - molecules can diffuse across their walls. This exchange of molecules is not possible across the walls of other types of blood vessel.

63
Q

Exchange of molecules into cells

A
  • oxygen diffuses through the capillary wall, into the tissue fluid, and the cells
  • glucose diffuses from the blood plasma, across the capillary walls to the tissue fluid, and then to the cells
64
Q

Exchange of molecules out of cells

A
  • carbon dioxide diffuses from the cells into the tissue fluid, then across the capillary walls into the blood plasma
  • the waste product urea diffuses from the cells of the liver, to the tissue fluid, and then across the capillary walls into the blood plasma
65
Q

Structure of heart

basic overview

A

The heart has four chambers - two atria and two ventricles.

66
Q

Flow of blood through the heart

A

Blood enters the heart through the atria. Blood from two vena cavae enters the right atrium. Blood from the pulmonary veins enters the left atrium.The atria fill, followed by the ventricles. Blood is prevented from flowing back into the atria by heart valves.

67
Q

Path of blood leaving the heart

A

Blood leaves the heart in the body’s main artery - the aorta - from the left side, and the pulmonary artery, from the right.

68
Q

Humans have a double circulatory system. The heart pumps blood through two circuits:

A
  • The pulmonary circulation

- The systemic circulation

69
Q

The pulmonary circulation transports blood to the lungs. At the lungs:

A
  • oxygendiffuses into the blood from the alveoli - the blood becomes oxygenated
  • carbon dioxide diffuses from the blood into the lungs.
70
Q

The systemic circulation transports:

A
  • oxygen and nutrients to the body

- carbon dioxide and other wastes away from cells

71
Q

The heart
double circulation
which circulation system delivers blood to the extremities of the body?

A

The systemic circulation is under high pressure - it has to deliver blood to the extremities of the body.

72
Q

The wall of which ventricle are thicker?

Why ?

A

The walls of the left ventricle are thicker and contain more muscle than those of the right ventricle. This is to create more pressure on the blood ready for entering the systemic circulation.

73
Q

The pulmonary circulation is under lower pressure, because:

A
  • blood is delivered to the lungs only, which are very close to the heart
  • in a healthy person, this lower pressure is optimum for the diffusion of gases
74
Q

How many time does blood pass through the heart in one complete circulation of the body?

A

Blood passes through the heart twice in one complete circulation of the body.

75
Q

Describe the path of blood through one complete circulation of the body.

A

1) Deoxygenated blood from the body enters the right atrium
2) Blood passes from the right atrium to the left ventricle, then to the lungs.
3) Oxygenated blood from the lungs enters the left atrium.
4) Blood passes into the left ventricle through the aorta and into the body

Note that although this is shown as a sequence, the atria contract in unison, and when full, the ventricles also contract in unison. Part of the blood is being delivered to the body, while the remainder of the blood is being transported to the lungs. This means that oxygen can be picked up from the lungs, while at the same time, blood is also being delivered to the body.

76
Q

What is cardiac output?

A

Cardiac output is the total volume of blood pumped out by the left ventricle every minute.

77
Q

Cardiac out put equation

A

Cardiac output = stroke volume x heart rate

CO = SV x HR

78
Q

Units for cardiac output equation

A

CO = cm^3 per minute (cm^3/min)

SV = cm^3

HR = beats per minute (bpm)

79
Q

Relationship between:
Cardiac output and heart rate
cardiac output and stroke volume

A

If the heart rate increases, cardiac output increases. Also if stroke volume increases, cardiac output will increase.

80
Q

How exercise effects cardiac output

A

During exercise, the heart rate increases and the force of contraction of the ventricles increases, therefore cardiac output and stroke volume increase.

81
Q

Q. If the SV is 72 cm3 and the CO is 5400 cm3/min, what is the HR?

A

HR = CO/SV = 5400/72 = 75 bpm

82
Q

Circulation

one way flow

A

Blood must flow one way only through the circulatory system. Valves in the heart, aorta and veins ensure this one-way flow.

83
Q

All organisms need energy to carry out metabolic processes. This energy is used:

A
  • To drive the chemical reactions needed to keep organisms alive. An example is the reactions used to build complex carbohydrates, proteins and lipids from the products of photosynthesis in plants, and the products of digestion in animals.
  • Movement - in animals, energy is needed to make muscles contract, while in plants, it is needed for phloem transport.
  • For cell division.
  • To maintain constant conditions in cells and the body - homeostasis.
  • To move molecules against concentration gradients in active transport.
  • For the transmission of nerve impulses.
84
Q

Heat released through respiration

in animals

A

As animals respire, heat is also released. In birds and mammals, this heat is distributed around the body by the blood and helps to maintain a constant internal temperature.

85
Q

Respiration using oxygen to break down food molecules is called what?

A

aerobic respiration

86
Q

Aerobic respiration

glucose

A

Glucose is the molecule normally used for respiration - it is the main respiratory substrate. Glucose is oxidised to release its energy.

87
Q

word equation for arorbic respiration

A

glucose + oxygen → carbon dioxide + water (+ energy released)

88
Q

Chemical equation for aerobic respiration

A

C6H12O6 + 6O2 → 6CO2 + 6H2O

89
Q

Basic summary of respiration

A

The first stages of respiration occur in the cytoplasm of cells, but most of the energy released is in the mitochondria.

90
Q

Anaerobic respiration

overview

A

During anaerobic respiration, the oxidation of glucose is incomplete. The reaction therefore releases much less energy - around a nineteenth of the energy released during aerobic respiration.

91
Q

Anaerobic respiration

in animals

A

Animal muscles can respire anaerobically for short periods of time - even though the process is relatively inefficient, it’s better to continue respiring and be able to run away from danger - or run a race.

92
Q

Equation for which glucose in muscle is converted to lactic acid:

A

glucose → lactic acid (+ energy released)

93
Q

Anaerobic respiration in plants and microorganisms

Which plants and/or microorganisms do this?

A

Some plants, and some fungi such as yeast can respire anaerobically - it’s preferable to release less energy but remain alive.

94
Q

Anaerobic respiration in plants and microorganisms

alcohol

A

Glucose in yeast cells is converted to carbon dioxide and ethanol, which we refer to simply as ‘alcohol’. This reaction is also called fermentation:

glucose → ethanol + carbon dioxide (+ energy released)

95
Q

Anaerobic respiration in plants and microorganisms

where does it occur?

A

Anaerobic respiration occurs only in the cytoplasm of cells.

96
Q

Muscles need energy to contract. While exercising, the muscles need additional energy. Several changes take place in the body to enable this:

A
  • the breathing rate and volume of each breath increases to bring more oxygen into the body and remove the carbon dioxide produced
  • the heart rate increases, to supply the muscles with extra oxygen and remove the carbon dioxide produced
97
Q

Response to exercise

if insufficient oxygen is available to muscles

A

If insufficient oxygen is available to the muscles, for instance the exercise is vigorous and/or prolonged, the heart and lungs are unable to supply sufficient oxygen. Muscles begin to respire anaerobically. Lactic acid is produced from glucose, instead of carbon dioxide and water. Muscles continue to contract, but less efficiently.

98
Q

In the human body

During long periods of vigorous activity:

A
  • lactic acid levels build up
  • glycogen reserves in the muscles become low as more glucose is used for respiration, and additional glucose is transported from the liver
99
Q

The buildup of lactic acid produces what?

A

This build-up of lactic acid produces an oxygen debt.

100
Q

What happens as body stores of glycogen become low?

A

As body stores of glycogen become low, the person suffers from muscle fatigue.

101
Q

Aerobic and anaerobic respiration compared

presence of glucose

A

Aerobic respiration:
present

Anaerobic respiration:
absent or in short supply

102
Q

Aerobic and anaerobic respiration compared

Oxidation of glucose

A

Aerobic respiration:
Complete

Anaerobic respiration:
Incomplete. The products of respiration still contain energy.

103
Q

Aerobic and anaerobic respiration compared

Products of respiration

A

Aerobic respiration:
Carbon dioxide and water. The products do not contain stored chemical energy.

Anaerobic respiration:
Mammalian muscle - lactic acid. Plants and microorganisms - ethanol and carbon dioxide. The products still contain stored chemical energy.

104
Q

Aerobic and anaerobic respiration compared

Amount of energy released

A

Aerobic respiration:
Relatively large amount

Anaerobic respiration:
Relatively large amount

105
Q

Method of measuring the rate of respiration using a respirometer

A
  • The apparatus consists of two tubes, one containing the living organisms and the other with glass beads to act as a control.
  • Both tubes contain an alkali such as sodium hydroxide to absorb any carbon dioxide given off during respiration. This ensures that any volume changes measured in the experiment are due to oxygen uptake only.
  • Once the apparatus has been set up, the movement of the coloured liquid towards the insect will give a measure of the volume of oxygen taken up by the insect for respiration.
  • The reduction of volume in the tube increases pressure causing the coloured liquid to move.
  • The distance moved by the liquid in a given time is measured will provide the volume of oxygen taken in by the insect per minute.
  • Volume is given by volume of a cylinder V = (pi) x r^2 x h, where h is the distance moved by the coloured liquid. The unit of rate of respiration is cm^3/min.

To investigate temperature the experiment is repeated at different temperatures, eg 10, 15, 20, 25, 30°C.

106
Q

Why do large multicellular organisms need transport systems while simple unicellular organisms do not?

A

Large organisms have a much smaller surface area to volume ratio compared to smaller ones

107
Q

How is carbon dioxide transported in the blood?

A

Carbon dioxide is transported dissolved in the blood plasma. Urea, hormones and digested food are also transported in the plasma.

108
Q

Which type of blood vessel contains valves?

A

vein

109
Q

What sort of circulatory system is the human circulatory system?

A

double

110
Q

Which chamber of the heart produces the highest pressure in the blood?

A

The left ventricle produces the highest pressure as it needs to pump blood along the aorta to the head and the rest of the body.

111
Q

Compared with aerobic respiration, anaerobic respiration releases how much energy?

A

Less energy

112
Q

What is the name of the apparatus used to determine the respiration rate?

A

Respirometer