TYPES OF RESPONSE OR IRRITABILITY


How living things respond to its environment

This is not just about the organism responding to stimuli but the respond to growth and movement within the cell of an organism

One of the characteristics of a living thing is responding to stimuli. All living thing are capable of responding to internal and external stimuli. The ability to do this is called irritability or sensitivity. Through this means, plants and animals are able to detect and respond to changes in their environment.
So irritability is one of the basic characteristics of living organisms.






TYPES OF RESPONSES

OR IRRITABILITY
Animals responds to irritability quicker than plan does to external changes to or in their environment. Here it is worthy of note that only a part of plant respond to stimuli while the animals responds through their whole body.
Organs of higher animals that respond to stimuli are
1. Flowers
2. Leaf
3. Root
4. Stem
5. Tendril
There three major types of responses. These are
i. Tactic
ii. Nastic
iii. Tropic movements


TAXIS OR TACTIC MOVEMENTS

What is taxis or tactic movement?
Taxis or tactic movement/responses is a type of directional responses or movement in which a whole organism moves from one place to another in response to external stimuli such as light, temperature, water and certain chemicals.
So locomotion can be positive or negative


Examples of tactic movements are
1. Thermotaxis
2. Phototaxis
3. Hydrotaxis
4. Chemotaxis

1.

THERMOTAXIS:

this is the movement of organisms in response to temperature change or heat. Example is a snail moving from hot region to a cold region. And this is known as negative Thermotaxis
2.

PHOTOTAXIS:

Phototaxis is the movement in response to light stimuli by organisms. It is the source of light to organisms. E.g. Euglena moving away from sunlight.
3.

HYDROTAXIS:

Hydrotaxis is the response of the whole organism in response to water or humidity, example is the woodlouse moving towards areas of high humidity
4.

CHEMOTAXIS:

Chemotaxis is the movement of organism in response to a chemical stimuli. Example is Amoeba and Paramecium moving away from chemicals










2.

NASTISM OR NASTIC MOVEMENTS

WHAT IS NASTISM?
WHAT IS NASTIC MOVEMENTS?
Nastism is a type of response in which a part of a plant moves in a non-directional stimuli such as changes in light density,
The respond movement is also non-directional. Examples of Nastic movements are as follows
i. Closing of the morning glory flower when the light intensity is low
ii. Petals of sun flower which opens in the light and closes in the dark
iii. The folding of the leaflets of the Mimosa plant when it is touches
iv. The closing of the leaflets of the Flamboyant tree. That is sleeping movement due to low light intensity.







TROPISM OR TROPIC MOVEMENTS

WHAT IS TROPISM?
Tropism is a type of response in which a part of a plant moves in response to a directional stimulus. The direction of the movement is related to that of the stimulus and it is positive if the plant part grows towards the stimulus and it is negative if the plant part grows away from the stimulus.
Tropism are very slow growth movement. They are named according to the stimuli, e.g. Phototropism which is a response to light and Hydrotropism which is response to water.

EXAMPLES OF TROPIC RESPONSES

Names of stimuli, names of response and examples of it

1. LIGHT==phototropism type of response====examples are how the shoots of plants bends towards light which is known as =positive phototropic.. while the roots of plants moves away from light also known as negative phototropic
2. GRAVITY==GEOTROPISM== examples are the shoots of green plants bends away from gravity which also known as negatively Geotropic=while roots bends towards gravity also known as positively Geotropic
3. WATER==Hydrotropism==example is how the roots of plants move towards moisture which is known as positively Hydrotropic= while the shoot bends away from moisture also known as negatively Hydrotropic
4. TOUCH==THIGMOTROPISM==example is how the tendrils of a climbing plant twine around a support as a positive response to touch== while the roots grows away from touch as a negative response

The differences between TROPIC AND nastic movements. These are the major difference between tropic and nastic movement and response to either internal or external stimuli. It cannot be said enough here about the difference between tropic and nastic movement in response to stimuli in living organisms; here I am going to treat a little of the varied difference between tropic and nastic movement

TROPIC MOVEMENT

The question is how do we recognize a tropic movement? The following are the various ways to recognize a tropic movement
1. Tropic movement involves growth movement
2. Topic movement involves responding to unilateral stimuli
3. In tropic movement, response is very slow
4. Growth in tropic movement is irreversible
5. Tropic movement is not due to turgor
6. Tropic movement is a directional, positive or negative response to stimuli

Here are the various ways or major

differences that makes nastic movement different from tropic movement.

They are as follows
1. Nastic movement is not a growth movement
2. Organisms do not respond to diffuse stimuli in nastic movement
3. In nastic movement, responding to stimuli is very fast
4. Growth in Nastic movement is reversible
5. Nastic movement can be due to changes in cell turgor
6. Nastic movement is non-directional. It is neither positive nor negative response



ENVIRONMENTAL FACTORS THAT EVOKE RESPONSE

There are so many environmental factors that evokes response in living organisms. They are but limited to the following,
i. Light
ii. Water
iii. Gravity
iv. Temperature and
v. PH

The factors effects plants and animals in so many ways. Worthy of note is that equal exposure of plant (CELL) to light diffuses their hormones equally and this makes the growth of plants upward and upright.
Therefore placing a plant in a horizontal position causes an unequal diffusion of hormones. This will make the shoot negatively geotropic by growing upwards. So if a p0lant is starved of adequate light, it tends to respond to any source of light available. The shoot will then respond positively to the source of light while the root will respond negatively.
Invariably the smaller plants in an attempt to get light from the top, automatically grows taller. And so this type of Growth response is called AETIOLATION

ROLES OF AUXINS IN GROWTH MOVEMENT

Auxin is the best known amongst plant hormones. They control tropism by stimulating growth in roots and shoots.
Auxins are produce by the cells in the shoots from where they diffuse to the growing regions. For example, Auxins influence phototropic movements in plants in the flowing ways
i. Auxins are produces at the tip of the shoot.
ii. Auxins diffuse or migrate to growing areas of the plants
iii. The shoot of plants will definitely grow straight as long as there is equal concentration of light and Auxins in all sides
iv. Unilateral illumination of the shoot causes the Auxin to the sides of the shoot moving away from light
v. The increase in the number of Auxin in a particular area makes growth faster
vi. This eventually causes a curvature or bending towards the source of the light thereby resulting in positive Phototropism

HOW LIGHT BRINGS ABOUT TROPIC MOVEMENT IN ROOT AND STEM OF A FLOWERING PLANT

SHOOT OR STEM
1. When unilateral light falls on the stem, the Auxin which is also known as the growth hormone is displaced from the lighted to the dark side.
2. The increase in Auxin concentration on the dark side increases growth on that side, causing the stem to bend toward light known as positive phototropism
ROOT
I. The Auxin is displaced from the lighted side to the dark side
II. The increase in Auxin concentration in the root retards growth in the dark side, so causing the root to bend away from the light which is known as negative phototropism



MOVEMENT OF THE CELL

What is movement in living organism?
Do living things actually move from place to place?
So here I will be writing in details of the various way that living organisms including single cell organisms move from place to place in search of food or responding to internal or external stimuli
So the question now is what is movement?

Movement is the ability of living organisms to move from one place to another. Reasons for movement of cell or living organisms are so many but I will like to write on a few of the following.
i. Searching for food
ii. Escape from danger
iii. Positive and negative response to stimuli
iv. For reproduction sake
All organisms that can move from place to place are equipped with various organelles or Organs and other mechanism for movement


CYCLOSIS

WHAT IS THE MEANING OF CYCLOSIS?
So what is Cyclosis? Cyclosis is the circulation of protoplasm in cells.
Cyclosis occurs in protozoa organisms like Amoeba, and it is generally known as amoeboid movement.
Amoeboid movement is aided by a mechanism called cytoplasmic streaming. It involves the principle of gel-sol conversion of cytoplasm i.e. the varying of the viscosity of cytoplasm and the accompanying fluid pressure at different points within the cell membrane

Movement in amoeba is accompanied by a continuous streaming of the cytoplasm in a forward direction.
This movement is accompanied by the locomotion of the whole cell. In the forward direction, the central plasma sol is converted to plasma gel which remain attached to the inner wall of the plasma membrane but at another point the gel is reconverted in to a sol thereby creating what is called pseudopodium in front and the driving force from behind

TYPES OF ORGANELLES FOR MOVEMENT

There are various types of organelles or organs used by cellular organisms for movement. Organelles which causes movement affecting the whole cells and leading to cellular locomotion in organisms like paramecium, Chlamydomonas and Euglena are flagella and cilia

What is a flagella?

Flagella are long whip-like projections on the cell surface. They are usually one or two on a cell.
Organisms that moves with the aid of a flagella or possess flagella for movement are as follows
1. TRYPONOSOME
2. CHLAMYDOMONAS
3. SPERMATOZOA
Singular-flagellum
Plural-flagella






3

REPRODUCTION IN LIVING ORGANISMS

What is reproduction?
How reproduction does takes place?
Here you will see the importance of reproduction as concerns living things


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HERE YOU WILL FIND EVERY AVAILABLE TOPICS ABOUT AGRICULTURAL SCIENCE AND BIOLOGY. AND THE LINKS TO THEIR VARIOUS SOURCES.
1. DEVELOPMENT OF AGRICULTURE
2. IMPORTANCE OF AGRICULTURE
3. SUBSISTENCE AGRICULTURE
4. COMMERCIAL AGRICULTURE
5. PROBLEM OF AGRICULTURAL DEVELOPMENT
6. SOLUTIONS TO POOR AGRICULTURAL DEVELOPMENT
7. AGRICULTURAL LAWS AND REFORMS
8. ROLES OF GOVERNMENT IN AGRICULTURAL DEVELOPMENT
9. AGRICULTURAL POLICIES
10. PROGRAM PLANNING IN AGRICULTURE
34.
FORESTRY
35. WILDLIFE CONSERVATION
36. FACTORS AFFECTING LAND AVAILABILITY
37. TOPOGRAPHY
38. SOIL
39. BIOLOGICAL FACTORS
40. SOCIAL-ECONOMIC FACTORS
41. ENVIRONMENTAL FACTORS AFFECTING AGRICULTURAL PRODUCTION
42. CLIMATIC FACTORS AFFECTING AGRICULTURAL PRODUCTION
43. TEMPERATURE
44. RAINFALL
45. WIND
46. SUNLIGHT
47. SOLAR RADIATION
48. BIOTIC FACTOR AND AGRICULTURAL PRODUCTION
49. PESTS
50. BIRDS
51. DISEASES
52. SOIL MICRO-ORGANISMS
53. SOIL PH
54. ROCK FORMATION
55. IGNEOUS ROCK
56. SEDIMENTARY ROCKS
57. METAMORPHIC
58. SOIL AND ITS FORMATION
59. FACTORS OF SOIL FORMATION
60. LIVING ORGANISM
61. PARENT MATERIALS
62. SOIL FORMATION TOPOGRAPHY
63. PROCESS OF SOIL FORMATION
64. WEATHERING
65. PHYSICAL WEATHERING
66. CHEMICAL WEATHERING
67. PRESSURE
68. WATER
73. BIOLOGICAL WEATHERING
74. CHEMICAL AND BIOLOGICAL COMPOSITION OF THE SOIL
75. SOIL WATER
76. MICRO AND MACRO NUTRIENTS
77. SOIL MICRO ORGANISM
78. PROPERTIES OF SOIL
79. SOIL STRUCTURE
80. SANDY SOIL
81. CLAY SOIL
82. LOAMY SOIL

83. SOIL TEXTURE
84. IDENTIFICATION OF SOIL TYPES THROUGH EXPERIMENTS
85. RETENTION OF WATER BY VARIOUS SOIL TYPES
86. DETERMINATION OF SOIL PH REACTION
87. COLORIMETRIC DETERMINATION OF SOIL PH LEVEL
88. PH SOIL TEST
89. PLANT NUTRIENTS
90.
MACRO NUTRIENTS IN GENERAL
112.
THE MAINTENANCE OF SOIL FERTILITY
113. CROP ROTATION
114. APPLICATION OF ORGANIC MANURES
115. FARM YARD MANURE
116. APPLICATION OF INORGANIC MANURE

117. LIMING
118. FARMING PRACTICES
119. BUSH BURNING
120. CLEARING

121. FERTILIZER APPLICATION
122. ORGANIC MANURING
123. FARM YARD MANURE

124. HUMUS
125. COMPOST
126. CROP ROTATION
133. FARM POWER AND MACHINERY
134. SOURCES OF FARM POWER
135. HUMAN SOURCE
149.
PLOUGHS
142.
FIELD MACHINES
157.
PLANTERS
164.
SIMPLE FARM TOOLS
165. AGRICULTURAL MECHANIZATION
166. THE CONCEPT OF MECHANIZATION


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