Match the organelle to its nickname: (a) Mitochondria (b) Lysosomes (c) Ribosomes. Then describe what happens to a piece of bread (starch) from the moment it enters the mouth until its nutrients reach the blood.

Question

Accepted Answer

ORGANELLE NICKNAMES: (a) Mitochondria = 'POWERHOUSE of the cell.' They are the site of CELLULAR RESPIRATION where glucose and oxygen are converted to ATP (energy), CO₂, and water. ALL energy-requiring activities in the cell depend on ATP from mitochondria. (b) Lysosomes = 'SUICIDE BAGS.' They contain powerful digestive enzymes that break down worn-out organelles, bacteria, and cell debris. When a cell dies, lysosomes may burst and digest the entire cell — hence the name. (c) Ribosomes = 'PROTEIN FACTORIES.' They are the site of PROTEIN SYNTHESIS — they read instructions from mRNA and assemble amino acids into proteins. JOURNEY OF BREAD (STARCH): (1) MOUTH: Bread is chewed (mechanical digestion). Saliva is released. Salivary AMYLASE begins breaking starch → maltose (a sugar). Bolus (food ball) formed. (2) STOMACH: Bolus enters stomach. HYDROCHLORIC ACID (HCl) creates acidic environment. PEPSIN breaks proteins → peptides. Starch digestion by amylase STOPS (amylase is inactivated by acid). (3) SMALL INTESTINE: BILE (from liver, stored in gall bladder) emulsifies any fats. PANCREATIC AMYLASE resumes starch → maltose. MALTASE in intestinal lining breaks maltose → GLUCOSE. Complete digestion of starch to glucose. VILLI (finger-like projections) absorb glucose into the blood through capillaries. Glucose enters the bloodstream and travels to all cells.

Practice — Biology — Cell, Tissues, Diversity, Nutrition & Human Body Systems

Sign in to save attempts to your dashboard and track your accuracy over time

Find a verified tutor

Join a live course

Browse coaching centres

About

Categories

Support

Documentation

Get Study Tips & Updates

Download Our App

Download for iOS

Download for Android

Popular Cities