Reasoning Qs Flashcards
Why do monozygotic twins have the same sex?
Both twins developed from the same zygote have the same genes. Hence, they have the same sex and exactly identical features.
What are twins?
Two children which develop together and are born together are called twins.
Do identical twins develop asexually or sexually? why?
Since they are the product of mitosis, these twins are often considered to have developed asexually.
How many types of twins are the there? What they called?
Twins are of two types :
One of which is called Identical or monozygotic twins.
The other is called Nonidentical or dizygotic twins.
What is an Archaeopteryx?
An Archaeopteryx is a fossil bird which lived 150 million years ago.
What were the unique traits of Archaeopteryx?
It was an unusual bird as it had:
- a toothed beak,
- a long tail with many vertebrae ,and
- a pair wings containing movable fingers with claws.
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NOTE: All these traits are related to both birds and reptiles.
Why is archaeopteryx considered a connecting link between reptiles and birds?
Keeping in mind the fact that evolution is a slow process and transits through many intermediate organisms, scientists think that the Archaeopteryx is a strong evidence for link between birds and reptiles.
Why do muscles require energy?
In order to allow locomotion, muscles require energy in the form of ATP (Adenosine Tri Phosphate)
When does fermentation/Anaerobic respiration occur in humans?
If person involves in prolonged and heavy exercise when enough oxygen is unavailable, muscles gain ATP through fermentation/Anaerobic respiration.
How is anaerobic respiration different from aerobic respiration?
Normally glucose (source of quick energy) would be converted into CO2 and water , but in case of anaerobic respiration, glucose is converted into lactic acid, which accumulates in the muscle.
What is the cause of muscle fatigue?
Because it is poisonous, lactic acid caused the bearer to feel pain which causes tiring condition of the muscle known as muscle fatigue.
What signal does the accumulation of lactic acid give to the human body? and why?
Since high concentration of lactic acid in the body is hazardous to a person’s life , it is a natural signal by the body that the person must stop the physical activity and compensate for lack of oxygen so the lactic acid is removed.
What is cleavage?
The series of repetitive mitotic divisions taking place in a fertilized ovum is called cleavage.
Why is cleavage in birds considered restricted?
Cleavage in birds is restricted to blastodisc which lies on top of the yolk towards the animal pole of the zygote.
Why is cleavage in birds “Discoidal cleavage” ?
The yolk of the ovum remains undivided (with the blastodisc on top of the yolk), which is why this type of cleavage is called “Discoidal cleavage”.
