Tag: endocrine system in humans

Colostrum is a milky fluid that comes from the breasts of humans, cows, and other mammals the first few days after giving birth, before true milk appears. It contains proteins, carbohydrates, fats, vitamins, minerals and proteins (antibodies) that fight disease-causing agents such as bacteria and viruses. Antibody levels in colostrums can be 100 times higher than levels in regular cow’s milk.

Chameleons camouflage themselves in a variety of different ways but most famously by changing the colour and pattern of their skin. Most chameleons can change colour and they do this by expanding or contracting cells in their skin that contain different pigments. They can blend into their surroundings by altering the colour of their skin to match the background. Chamaeleon (girgit) shows protective colouration with its surrounding e.g., twig. 

Imprinting is defined as a learning process in which an offspring establishes species specific behaviour patterns along with recognition and attraction towards individuals of own species and even certain specific individuals (like parents). This process is classified as phase sensitive learning independent of external behaviour or other characteristics. In case of salmons, it has been theorized by Wisby and Hasler that they imprint on the unique odour of the natal water and as adults follow the same odour cues to their birth homes for spawning. Hence the correct answer is 'Imprinting'.   

Colostrum (also called as first milk) is the thin yellowish fluid secreted by the mammary glands at the time of parturition and which precedes the production of true milk. It provides a nursing infant with essential nutrients and infection-fighting antibodies (called as immunoglobulin) to protect the newborn against disease. IgA is the major immunoglobulin in colostrum. It protects from inhaled and ingested pathogens.

1. During mating, a male generally shows agressive behaviour as a form of superiority over other fellow males.
   2. Pheromones are used as a form of communication between two mating species.
   3. A male generally marks it's territory inorder to avoid anymore competition for mating.
   4. Visual communication is primarly used to locate and identify the mating partner.
   So, the correct option is 'Search image'.

So the correct answer is 'instinctual'.

Fish are given food at the same time as a tap on their glass bowl and soon learn to approach when a tap sounds even in the absence of food - it is an example of Classical conditioning.

A form of learning that occurs during a brief genetically determined critical period shortly after birth is called as imprinting. Habituation occurs throughout the life where individual learn to ignore the irrelevant stimuli. Reflex is a response to external or internal stimuli experienced throughout the life. Instinct and dominance are innate behaviours. The correct answer is D.

Because archegonia of pteris secrete a chemical malic acid which attracts only sperms of Pter!s thermostatically.