Prepare for NEET Biology Plant Growth and Development with MCQs & PYQs on NEET.GUIDE. Get free practice, previous year questions, and expert insights on plant hormones and growth regulators.
During human embryonic development, the formation of the primitive streak marks a crucial step. Which of the following statements regarding the primitive streak is INCORRECT?
It marks the beginning of gastrulation.
It defines the embryo's axes.
It is the source of mesoderm and endoderm.
It persists throughout development.
The archenteron in a developing gastrula will eventually give rise to which structure in the adult organism?
Neural tube
Notochord
Digestive tract
Coelom
During oogenesis in mammals, polar bodies are formed. Which statement best describes the function of polar bodies?
To provide nutrients to the developing oocyte.
To allow for the reduction of chromosome number while retaining most of the cytoplasm in the oocyte.
To initiate the process of fertilization.
To guide the sperm towards the oocyte.
Which PGR is most likely responsible for the phenomenon observed when a plant bends towards a light source, even if the light source is unidirectional and doesn't illuminate the entire plant?
Cytokinin
Gibberellin
Auxin
Abscisic Acid
A biennial plant requiring vernalisation is induced to flower after prolonged exposure to low temperatures. However, immediately after this cold treatment, if the plant is exposed to a brief period of high temperatures, the effect of vernalisation is nullified. This phenomenon is known as:
Devernalisation
Stratification
Photoperiodism
Vernalisation reversal
Which of the following statements about vernalisation is INCORRECT?
Vernalisation is the promotion of flowering by a period of low temperature.
The cold treatment is perceived by the shoot apical meristem.
Vernalisation always promotes flowering in all plant species.
The vernalisation stimulus can sometimes be transmitted through grafting.
Which extraembryonic membrane in mammals is involved in the formation of the placenta?
Amnion
Yolk sac
Allantois
Chorion
Which hormone plays a crucial role in metamorphosis in amphibians?
Growth Hormone
Insulin
Glucagon
Thyroxine
Which of the following is NOT a characteristic of growth?
Increase in size or quantity
Development and maturation
Progress and advancement
Decline in quantity or size
What is the term for the permanent cessation of growth in a cell or organ?
Hyperplasia
Hypertrophy
Apoptosis
Senescence
