stem 11 BIOLOGY FIRST QUARTER

Random Cells Facts

The average human being is composed of around 100 Trillion individual cells!!!

- It would take as many as 50 cells to cover the area of a dot on the letter i

Theodor Schwann

He studied plants and animal cells

Determine that all animals are made of cells

Published the Ist statement of the cell theory.

Antonie van Leeuwenhoek

He improved microscope lens quality.

The first to document living microorganisms, or "animalcules

He opened the field of microbiology

Importance of Historical Analysis

Why Study Scientific History?

1 Enhances our understanding of how knowledge evolves.

2 Demonstrates the significance of evidence and observation.

3 Unveiling collaboration among scientists.

4 Utilizes secondary sources such as books, articles, and journals

A cell is the smallest functional and structural unit of all living organisms

An organism is any living thing that carries out its own life processes.

Robert Hooke was the first to describe cells. He looked at the bark of a cork tree under a microscope.

What is a Cell

Matthias Schleiden

He studied plants under a microscope

He concluded that all plants consist of cells.

He helped establish the cell as life's fundamental unit.

Rudolf Virchow

He strengthened modern cell theory.

He emphasized diseases start in cells, not organs or tissues

He said cells arise from pre-existing cells, or "omnis cellula e cellula.

Robert Hooke

He studied cork using a microscope in 1665.

Hooke noticed box-like structures he called "cells".

He published his findings in Micrographia.

Cells are small because their size is limited by their outer surface area.

If cells get too large, they cannot take in enough materials or get rid of enough wastes.

The surface area-to-volume ratio of a cell is the ratio of the outer surface to the cell s volume.

Why are most cells small?

Modern Cell Theory

1. The cell contains hereditary information(DNA) which is passed on from cell to cell during cell division.

2. All cells are basically the same in chemical composition and metabolic activities.

3. All basic chemical & physiological functions are carried out inside the cells.(movement, digestion,etc)

4. Cell activity depends on the activities of sub-cellular structures within the cell(organelles, nucleus, plasma membrane)

All living organisms are composed of cells.

The cell serves as the fundamental unit of life.

All cells originate from previously existing cells.

What is Cell Theory?