Medical Entrance Preparation

Heart:
The heart is a muscular organ about the size of a fist, located just behind and slightly left of the breastbone. The heart pumps blood through the network of arteries and veins called the cardiovascular system.

The heart has four chambers:

The right atrium receives blood from the veins and pumps it to the right ventricle.

The right ventricle receives blood from the right atrium and pumps it to the lungs, where it is loaded with oxygen.

The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle.

The left ventricle (the strongest chamber) pumps oxygen-rich blood to the rest of the body. The left ventricle’s vigorous contractions create our blood pressure.

The coronary arteries run along the surface of the heart and provide oxygen-rich blood to the heart muscle. A web of nerve tissue also runs through the heart, conducting the complex signals that govern contraction and relaxation. Surrounding the heart is a sac called the pericardium.

Q.Epipetalous stamen and axile placentation are characteristics of:
a. Liliaceae b. Solanaceae
c. Gramineae d. Brassicaceae

Solution:b
Details:The condition when stamens are attached to petals are called epipetalous condition.It is found in Solanaceae family.
Placentation is the arrangement of ovules within the o***y. Basically there are major types of placentation.

a.Marginal Placentation:
-Leguminoseae

b. Axile placentation:
-Solanaceae
-Malvaceae
-Liliaceae

c.Parietal placentation:
-Crucifereae/Brassicaceae
-Cucurbitaceae

d.Basal placentation:
-Asteraceae
-Gramineae

e.Superficial placentation:
-Nymphea
-Liliaceae

f. Free Central Placentation:
-Dianthus.