Enzyme and carbohydrates dominate in the digestive tract of
carnivores
omnivores
parasites
herbivores
If there are 4 microspore mother cells in an anther, what will be the number of pollen grains?
4
8
12
16
The correct sequence for the formation of chemicals on the primitive earth is
NH3, protein, carbohydrate and nucleic acid
NH3, water, nucleic acids and proteins
NH3, nucleic acids, protein and carbohydrate
protein, carbohydrate, water and nucleic acids
Which country has the greatest contribution for the hole formation in ozone layer?
USA
Germany
Russia
Japan
Radio-tracer technique shows that DNA is in
single-helix stage
double-helix stage
multi-helix stage
none of these
When paternal and maternal chromosomes change their materials with each other in cell division this event is called
synapsis
crossing over
bivalent forming
dyad- forming
B.
crossing over
Crossing over is the mutual exchange of segments of homologous chromatids during first meiotic prophase.
Synapsis is the fusion of chromosome pairs at the start of meiosis.
DNA replication precedes the start of Meiosis I. During Prophase I, homologous chromosomes pair and form synapses. The paired chromosomes are called bivalents and the formation of chiasmata caused by genetic recombination becomes apparent.
Dyad formation is a double chromosome resulting from the splitting of a tetrad during meiosis (germ cell formation).
When a natural predator (living being) is applied on the other pathogen organism to control them, this process is called
biological control
genetic engineering
artificial control
confusion technique