Notes, summaries, assignments, exams, and problems

Early Foundations and Key Milestones in Plant Tissue Culture

The science of plant tissue culture originates from the discovery of the cell, followed by the postulation of cell theory. In 1838, Schleiden and Schwann proposed that the cell is the basic structural unit of all living organisms. They envisioned that a cell is capable of autonomy and, therefore, it should be possible for each cell, if given the right environment, to regenerate into a whole plant. Based on this premise, in 1902, German physiologist Gottlieb Haberlandt for the first time attempted to culture isolated single palisade cells from leaves in Knop’s salt solution enriched with sucrose. The cells remained alive for up to one month, increased in size, accumulated starch,... Continue reading "Milestones in Plant Tissue Culture Development" »

Respiratory System Basics

Respiratory Key Terms

• Dyspnea: Difficulty breathing
• Orthopnea: Difficulty breathing when lying flat
• Tachypnea: Abnormally fast breathing
• Bradypnea: Abnormally slow breathing
• Hemoptysis: Coughing up blood
• Hypoxia: Tissue oxygen deficiency
• Clubbing: Fingertip rounding due to chronic hypoxia
• Barrel chest: Increased chest diameter often from emphysema
• Cyanosis: Bluish skin or mucous membrane discoloration from low oxygen
• Rales/Crackles: Abnormal lung sounds indicating fluid
• Wheezing: High-pitched whistling from narrowed airways
• Rhonchi: Low-pitched rattling sounds (often due to secretions)
• Productive cough: Cough producing mucus or sputum
• Hypertonia: Increased muscle tone causing stiffness
• Hypotonia: Decreased muscle tone making muscles

Amputations are classified based on the specific level at which a limb is removed. This classification typically follows anatomical regions and varies depending on whether it involves the upper or lower limb. This document provides a detailed breakdown by anatomical region:

Upper Limb Amputation Levels

Partial Hand Amputations (Transphalangeal)

• Finger Amputation: Removal of one or more fingers at the distal, middle, or proximal phalanx level.
• Thumb Amputation: Particularly significant due to its importance in grip function.
• Metacarpal Amputation: Loss of part or all of the hand while preserving the wrist.

Wrist Disarticulation

• Wrist Disarticulation: Amputation through the wrist joint, preserving the forearm bones.

Below Elbow Amputation (Transradial)

Review of Art Spiegelman's Maus

Maus by Art Spiegelman is a groundbreaking graphic novel that tells the true story of Vladek Spiegelman, a Jewish survivor of the Holocaust, as narrated by his son, Art. Combining historical events with personal struggles, the novel explores trauma, memory, and the complexities of father-son relationships.

One of the most striking aspects of Maus is its artistic style. Spiegelman represents different groups using animals—Jews as mice, Nazis as cats—which serves as a powerful metaphor for oppression and survival. The black-and-white illustrations enhance the raw and emotional tone of the story, making it even more impactful.

The novel alternates between past and present, depicting both Vladek’s survival and... Continue reading "Art Spiegelman's Maus: A Holocaust Narrative" »

Acid Value Determination in Oils: Principle and Procedure

Here's an explanation of the principle and procedure involved in determining the acid value of an oil sample:

Principle

The acid value of an oil sample is a measure of the amount of free fatty acids present in the oil. The principle of the acid value determination is based on the reaction between the free fatty acids in the oil and a strong base, such as potassium hydroxide (KOH). The reaction is as follows:

RCOOH (Free Fatty Acid) + KOH → RCOOK (Potassium Salt) + H₂O

Procedure

Here's the step-by-step procedure for determining the acid value of an oil sample:

1. Apparatus

• 250 mL Erlenmeyer flask
• Burette
• Pipette
• Volumetric flask
• Phenolphthalein indicator

2. Reagents

• Potassium hydroxide (KOH) solution

1. Anagram Detection: C++ String Comparison

This C++ program determines if two input strings are anagrams of each other. It achieves this by converting both strings to lowercase, sorting their characters alphabetically, and then comparing the sorted strings. If they are identical, the original strings are considered anagrams.

#include<bits/stdc++.h>
using namespace std;

int main(){
    string s2,s1;
    cin>>s1>>s2;
    transform(s1.begin(),s1.end(),s1.begin(),::tolower);
    transform(s2.begin(),s2.end(),s2.begin(),::tolower);
    sort(s1.begin(),s1.end());
    sort(s2.begin(),s2.end());
    cout<< (s2==s1);
}

2. Array Subarray: C++ Sliding Window Minimum

This C++ program attempts to find the maximum of minimums within... Continue reading "C++ & C Programming Solutions: Algorithms & Patterns" »

File Operations

• ls — List files and directories (-a for hidden, -l for detailed)
• cd [directory] — Change directory
• mkdir [directory] — Create directory
• cp [source] [destination] — Copy files/directories (-r for recursive)
• mv [source] [destination] — Move or rename files/directories
• rm [file] — Remove files (-r for recursive)
• chmod [permissions] [file] — Change file permissions
• chown [user]:[group] [file] — Change file ownership

System Monitoring

• top / htop — Monitor system processes
• ps — List running processes
• df -h — Display disk space usage
• free -m — Show memory usage

Networking Commands

• ifconfig / ip a — Display network interfaces
• ping [host] — Test network connectivity
• netstat -tuln — List network connections
• nmap [IP] — Scan