Chapter 3 Cells

Chapter 3 Cells - Chapter 3 Cells 3.1 All organisms are...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 3 Cells 3.1 All organisms are made of cells - The most basic unit of any organism is the cell - Cell : The smallest unit of life that can function independently and perform all the necessary functions of life - Robert Hooke was the first to use the term cell - 3 dimensional structure - Contains DNA - Eggs, the most visible cell - All plants and animals are made entirely of cells - Every cell arises from the division to another cell - The average human is made up of at least 60 trillion cells - Cell theory : (1) All living organisms are made up of one or more cells and (2) all cells arise from other, pre-existing cells - Unifying theory and universally accepted - All life and all cells have been produced by a continuous line of cells 3.2 Prokaryotic cells are structurally simple, but there are many types of them - Every cell breaks into 2 basic categories 1. Eukaryotic Cell : Has a central control called a nucleus, which contains the cell’s DNA. Organisms composed of eukaryotic cells are called eukaryotes 2. Prokaryotic Cell : Does not have a nucleus; DNA resides in the middle of the cell. Organisms consisting of a prokaryotic cell is called a prokarytoe - Prokaryotes… - First cells on earth - One-celled organisms and invisible - 4 Basic Structures 1. Plasma/Cell Membrane : Encompass the cell. Anything inside the plasma is referred to as “intracellular” and everything outside is “extracellular” 2. Cytoplasm : Jelly-like fluid that fills the inside of the cell 3. Ribosomes : Granular bodies where proteins are made, and scattered throughout the cytoplasm 4. Each prokaryote has one or more circular loops/linear strands of DNA Unique Features…
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
- Contain rigid cell wall - Cell Wall : Protects and gives shape to the cell - Contain flagellum - Flagellum : Long, thin, whip like projection that rotates like a propeller and moves the cell through the medium - Contain pili - Pili : Hair-like projections that help prokaryotes attach to surfaces - Bacteria can fuel activities in the presence/absence of oxygen - Bacteria, largest type of prokaryote 3.3 Eukaryotic cells have compartment with specialized functions - Everything visible is a eukaryotic organism - Not all eukaryotes are multi-celluar Ex: Protista, single celled, visible only with a microscope - Nucleus, chief distinguishing feature - Contain other specialized structure, called organelles that are enclosed separately within lipid membranes in the cytoplasm - Organelles enable eukaryotic cells - Creation of separate compartments with distinct areas where different chemical reactions can occur simultaneously - Endosymbiosis Theory : Explains the presence of 2 organelles in eukaryotes (chloroplasts in plants and algae, and mitochondria in plants and animals) - Chloroplast convert sunlight into a more usable form of energy - Mitochondria help harness the energy stored in food molecules - Endosymbiosis is supported by observations… 1. Chloroplast and Mitochondria have small amounts of DNA 2. Chloroplast and Mitochondria are similar in size to prokaryotic cells
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 10

Chapter 3 Cells - Chapter 3 Cells 3.1 All organisms are...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online