12th Class Biology Chapter 7

“Explore the cell cycle, its stages, and the crucial processes of cell growth, division, and replication that drive organism development.”

Biology Class 12 Chapter 7 Notes

​The Syndrome which is an example of trisomy of the sex chromosome is: Klinefelter’s syndrome

In incubating eggs artificially the incubators are usually regulated at temperature between: 36 – 38oC

For maximum growth the optimum temperature is 25 – 30oC and it least at: 5 – 10oC

From Hensen’s node,dorsal mesoderm is formed and is organized into: Somitcs

On the basis of structure and shape of the cap,two species of Acetabularia have been identified: A.crenulata & A.arabica

In addition to auxin which hormone also play important role in apical domince: Cytokinins

in plants regeneration is the basis of plant: Reptiles

Primary tissue is added by the: Apical meristem

Which one of the following condition is resulted from excess GH in adults: Acromegaly

If lobster loses its pincer claw a new claw: Regenerates

Deficiency of vasopressin or ADH by the pituitary gland leads to a disorder in which the patients kidney have lessoned ability to absorb water is: Diabetes insipidus

An ordered sequence of irrversible steps with each step setting up the necessary conditions for the next step is: Development

Which of the following hormones is not released by the anterior pituitary: Melanocyte – releasing hormone

Which prosess is characterized by movement and rearrangement of cells in the embryo: Gastrulation

In the chick the mesodermal cells migrate and caudally from both sides and create a mid line thickening called: Primitive streak

Parathyroid hormone acts to ensure that: Calcium levels in the blood never drop too low

In humans ,MSH(melanocyte-stimulating hormone): Regulates primary skin color

During elongation the cell volume increase up to 150 fold due to uptake of: Water

A plant has a growth pattern called: Open growth

The negative physiological changes in our body are said to be: Agning

Clear cytoplasm produces: Larval epidermis

In chordates the healing of fracture and repair of a skin wound are some other examples of: Regeneration

_______ regulates the kidney’s retention of water: Vasopressin (ADN)

Oxytocin is secreted by the endocrine gland named: Pituitary gland

The addrenaline cortex produces: Aldosterone

The actual reduction division is: Meiosis -I

Programmed and organized death of cell is known as: Apoptosis

Monqolism is the other name of: Turner’s syndrome

The condensation of chromosomes reaches to its maximum during: Leptotene

The chances of teenage mother having down’s syndrome child is: One in many thousand

Nerve cells and eye lens cells remain in stage for life time: G0

Which tumor is delocalized or has branches other than site of orgin: Malignant

Crossing over and random assortment of chromosomes are two significant happenings of: Meiosis

Phragmoplast is formed by vesicles originated from: Golgi complex

The series of changes which involve period of growths replication of DNA followed ny cell division may be named as: Cell cycle

Important : Review all previous years’ 12 class past papers for comprehensive practice and better exam preparation.

Leave a Comment