Yellow-fruit nightshade

This plant is called yellow-fruit nightshade or कन्टकरी. Its botanical name is Solanum virginianum. This thorny herb grows in wild, on roadside and near farms. 

It bears beautiful, purple flowers and brinjal-like fruit. 

It is considered to be a poisonous plant. However, it has several medicinal uses also.

Factors Affecting Photosynthesis

According to Blackman's law of limiting factors, if a chemical process is affected by more than one factor, then the rate of reaction will be determined by the factor which is nearest to its minimal value.

Photosynthesis is affected by factors like light intensity, carbon dioxide concentration, temperature and water. 

1. Light: if light increases, photosynthesis also increases upto a certain level. Then it remains constant. Plants need only 10% of the available light intensity of sunlight. Therefore, light is never a limiting factor except in case the plant is in shade or in dense forest. 

If the light intensity increases too much, it starts destroying the chlorophyll, thus, photosynthesis reduces. 

2. Carbon dioxide: if amount of carbon dioxide increases, photosynthesis also increases upto CO2 concentration of 0.05 %. Then photosynthesis reduces. 

Saturation level or optimum level of carbon dioxide for C4 plants is 360 microlitre per litre of air; and for C3 plants is 450 microlitre per litre of air. Thus, carbon dioxide is a limiting factor more for C3 plants. 

3. Temperature: if temperature increases, photosynthesis also increases upto a certain level. Then photosynthesis reduces. C3 plants have lower optimum temperature (18 to 24 degree celsius). C4 plants have a little higher optimum temperature (30 to 40 degree celsius). 

4. Water: if available water is more, photosynthesis increases up to a certain level. Then there is no effect. If water available is less, the stomata do not open fully. So absorption of carbon dioxide is less. Thus, photosynthesis will also be less. 

Camels of Rajasthan (India)

These are the camels of Rajasthan. The zoological name of camel is Camelus dromedarius. These are very large, strong and handsome creatures. They are reared mainly for milk and to carry load. Once they were abundant in this area but now they are in crisis. Their number is decreasing and they now need support. 

Squirrel

This is a northern palm squirrel (Funambulus pennantii). It has five black-brown stripes on its back. It lives on trees. It is quite active and playful creature. Children like to observe it sitting, playing or searching for food. It doesn't sit in one place; though in summer, it likes taking rest on wet ground in the shade of a tree. 

Krebs' Cycle

Pyruvic acid which is produced in glycolysis is transported into the mitochondria where it is converted into acetyl CoA. Then, CoA enters the Krebs' cycle that takes place in the matrix of the mitochondria. 

NADH2 and FADH2 are generated in the Krebs' cycle. 

Glycolysis

In cellular respiration, oxidation of glucose takes place. The initial stage of cellular respiration takes place in the cytoplasm. Glucose molecule is broken down through a series of enzyme-catalyzed reactions into two molecules of pyruvic acid. This process is known as glycolysis.

Note: The above notes in the image(s) are taken from a personal notebook which was initially not intended to be shared online. Please excuse the rough handwriting and the spelling errors, if any. 

Morpankhi plant

This is an oriental thuja (मोरपंखी) plant (Platycladus orientalis also called Thuja orientalis). 

It is a gymnosperm and belongs to cypress family. It is used as ornamental plant or as hedges in gardens. 

Canna flower

This is a flower of canna plant, also called canna lily (Canna sp) . 

The flowers may be yellow, orange, red etc or in a combination of these colours.

It is a monocot plant and looks slightly like a banana plant. 

It has contractile roots. 

Its rhizome is rich in starch. 

CAM Cycle and Photorespiration

Crassulacean Acid Metabolic Cycle or CAM cycle is found in in plants of crassulaceae family eg Kalanchoe pinnate (bryophyllum) and euphorbiaceae family eg Euphorbia sp, codiaeum variegatum etc. 

Photorespiration:

Photo respiration occurs in C3 plants. In C3 cycle, rubisco enzyme binds with carbon dioxide and and through the cycle it produces glucose. Some of the rubisco enzyme also binds with oxygen, if the amount of oxygen is high and temperature is high. Thus, the amount of glucose produced is less. Moreover, some of the glucose produced is also oxidized which causes further loss of glucose. This is called photo respiration because it is not the main respiration which takes place in mitochondria but another type of respiration which takes place in the presence of sunlight. 

C4 Cycle

Some tropical plants like maize, sugarcane, many grasses, sorgam, millet, many plants of asteraceae, many plants of brassicaceae etc show a special type of photosynthesis called C4 cycle or C4 pathway. In this type of pathway, the first product of carbon dioxide fixation (malic acid or aspartic acid) is formed in the cells of mesophyll. It is a 4 carbon compound. 

Malic acid is transferred to the bundle sheath cells where it is converted into pyruvic acid. Pyruvic acid then takes part in the C3 cycle or Calvin cycle.