Respiration Topic 12 1st year

Question 1

What is metabolism?

Answer 1

All the chemical reactions taking place in the body

Question 2

What is a metabolic pathway?

Answer 2

The process of respiration is divided into steps

Question 3

What are catabolic reactions?

Answer 3

breakdown reaction. Reactions which release energy like respiration

Question 4

What are anabolic reactions?

Answer 4

build up reactions. Reactions that use up energy like photosynthesis

Question 5

From where do cells obtain their energy to use it for their functioning?

Answer 5

From the breaking down of food, they manufacture from autotrophs or from heterotrophs. (if consumed)

Question 6

What is the food converted into?

Answer 6

glucose

Question 7

Define respiration

Answer 7

The oxidation of glucose into carbon dioxide and water with the release of energy. This energy is stored at ATP molecules

Question 8

Where does respiration take place?

Answer 8

In the mitochondria in every living cell

Question 9

What are the 2 types of respiration?

Answer 9

Aerobic and Anaerobic

Question 10

What is aerobic respiration?

Answer 10

The breakdown of organic molecules (usually glucose) in the presence of oxygen to release energy. Occurs in glycolysis and cellular respiration

This energy is stored as ATP molecules.

glucose +oxygen –> carbon dioxide + water + energy

Question 11

What is anaerobic respiration?

Answer 11

The breakdown of organic molecules without the presence of oxygen to release energy. This energy is also stored as ATP but less energy is produced in this reaction.

After glycolysis, fermentation occurs. This produces waste products such as lactic acid in humans and ethanol during alcoholic fermentation.

Glucose–> lactic acid + energy

Glucose –> ethanol + carbon dioxide

Question 12

What is glycolysis?

Answer 12

When glucose is broken down into smaller molecules to release energy for cells to use

Question 13

What molecules are also involved in cellular respiration?

Answer 13

First you have a high energy substance which is going to be broken down into a simple low energy substance

ATP
NAD
FAD
NADP+

Question 14

What are NAD,FAD AND NADP+?

Answer 14

They are electron transporters which have been released in respiration

Question 15

What does NAD and FAD stand for?

Answer 15

FAD: flavin adenine dinucleotide

NAD: Nicotinamide adenine dinucleotide

Question 16

What is oxidation and what is reduction?

Answer 16

Oxidation: loss of electrons
Reduction: gain of electrons

Question 17

From where do all processes in a cell get the energy to drive everything that happens in the body such as muscle contraction and active transport?

Answer 17

From ATP

ATP needs to be broken down into ADP by ATPase which catalyse the breakdown of ATP into ADP and make use of the energy released.

Question 18

Describe the structure of an ATP molecule

Answer 18

3 phosphates
1 nitrogenous base adenine
ribose

Question 19

True or false

ATP is only used as a short term energy store.

Answer 19

True

But it needs to be converted to ADP because the loss of one phosphate group liberates a lot of energy

Question 20

Mention some uses of ATP

Answer 20

1) Used to build up new substances in reactions needing energy (anabolic reactions) like protein sysnthesis from amino acids or making polysaccharides fom monosaccharides or DNA replication

2) For cellular movement: muscle contraction or ciliary action

3) To increase secretions: cells that secrete substances are rich in mitochondria because energy is needed to form the vesicles necessary for the secretions

4) For active transport. It provides the energy necessary to move substances against a concentration gradient

5) To activate chemicals