Question
Suggest a suitable reason for the heart having four separate chambers.
✓
Answer
Human heart has four chambers that is two auricles and two ventricles. Auricles are the small chambers whereas ventricles are the bigger ones. Presence of four chambered heart serves two purposes. First, it ensures complete segregation of oxygenated and deoxygenated blood. Second, blood is received by the upper chambers and is pumped out by the lower chambers. This segregation between received blood and sent blood increases the efficiency of the heart.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
- Draw a sectional view of the human heart and label on it, Aorta, Right Ventricle and Pulmonary Veins.
- State the functions of the following components of transport system:
- Blood.
- Lymph.
Compare the properties of ionic compounds and covalent compounds.
The pancreas is made up of two parts A and B. The part A secretes insulin whereas part B secretes pancreatic juice.
- Which part is functioning as an endocrine gland? Why?
- What is insulin and what effect does it have in the body?
- Name the disease which can be treated by giving insulin injection.
- What does pancreatic juice contain? Where does pancreatic juice go?
- Name the life process in which pancreatic juice is made use of.
You are given an organic compound having the molecular formula $C _3 H _8$. Give the name and formula of the compound formed:
a. When one H atom of $C _3 H _8$ is replaced by a Cl atom.
b. When one H atom of $C _3 H _8$ is replaced by a OH group.
c. When one H atom of $C _3 H _8$ is replaced by a CHO group.
d. When one H atom of $C _3 H _8$ is replaced by a COOH group.
e. When two H atoms joined to the middle carbon atom of $C _3 H _8$ are replaced by one O atom.
→a. When one H atom of $C _3 H _8$ is replaced by a Cl atom.
b. When one H atom of $C _3 H _8$ is replaced by a OH group.
c. When one H atom of $C _3 H _8$ is replaced by a CHO group.
d. When one H atom of $C _3 H _8$ is replaced by a COOH group.
e. When two H atoms joined to the middle carbon atom of $C _3 H _8$ are replaced by one O atom.
In question 44 , what are the combinations of character in the $F_2$ progeny? What are their ratios?
→When metal X is treated with a dilute acid Y, then a gas Z is evolved which burns readily by making a little explosion.
- Name any two metals which can behave like metal X.
- Name any two acids which can behave like acid Y.
- Name the gas Z.
- Is the gas Z lighter than or heavier than air?
- Is the reaction between metal X and dilute acid Y, exothermic or endothermic?
- By taking a specific example of metal X and dilute acid Y, write a balanced chemical equation for the reaction which takes place. Also indicate physical states of all the reactants and products.
- Define the following terms in the context of spherical mirrors:
- Pole.
- Centre of curvature.
- Radius of curvature.
- Principal axis.
- Draw ray diagrams to show the principal focus of (i) a concave mirror, and (ii) a convex mirror.
- In the following diagram, MM' is a concave mirror and AB is an object. Draw on your answer-sheet a ray diagram to show the formation of image of this object.
- Draw a diagram of the longitudinal section of flower and label on it sepal, petal, ovary and stigma.
- Write the names of male and female reproductive parts of a flower.
A compound $X$ is formed by the reaction of a carboxylic acid $C _2 H _4 O _2$ and an alcohol in presence of a few drops of $H _2 SO _4$. The alcohol on oxidation with alkaline $KMnO _4$ followed by acidification gives the same carboxylic acid as used in this reaction. Give the names and structures of:
a. Carboxylic acid.
b. Alcohol.
c. The compound X . Also, write the reaction.
→a. Carboxylic acid.
b. Alcohol.
c. The compound X . Also, write the reaction.
An object 3cm high is placed at a distance of 8cm from a concave mirror which produces a virtual image 4.5cm high:
- What is the focal length of the mirror?
- What is the position of image?
- Draw a ray-diagram to show the formation of image.