What is the relationship between $CO_2$ concentration and the rate of respiration?

Analogy type questions:
$(1)$ Krebs cycle : Hans Krebs :: Glycolysis : ......
$(2)$ Glycolysis : Absence of oxygen :: Krebs cycle : ......

In the hexose monophosphate shunt ($HMP$ shunt),the number of $CO_2$ molecules evolved is:

Which of the following processes involves the loss of two protons and two electrons?

Match Column-$I$ with Column-$II$ and select the correct option.

Column-$I$	Column-$II$
$a.$ Cis-aconitate	$i.$ $4 \ C$-compound
$b.$ $\alpha$-ketoglutarate	$ii.$ $3 \ C$-compound
$c.$ Fumarate	$iii.$ $6 \ C$-compound
$d.$ $1,3$-diphosphoglyceric acid	$iv.$ $5 \ C$-compound

Select the correct statements from the following:
$I-$ During respiration,plants take in $CO_2$ and release $O_2$.
$II-$ The surface of most cells in plants is in contact with air.
$III-$ The loose arrangement of parenchyma cells in leaves,stems,and roots creates a network of air spaces.
$IV-$ The energy released during respiration is stored in the form of $ATP$.
$V-$ Glucose is oxidized to release energy in only a single step.