True or False
In Single-celled organisms, each cell is responsible for all the work to keep the organism alive. In multi-cellular organisms, like the human body, cells do not work independently, but form cell communities that work together.
True
True or False
Individual body cells are specialized to perform their own unique purpose.
True
True or False
Muscle cells look and act like skin cells, and blood cells look and act like brain cells.
False
Cell specialization is obvious. Different types of cells are easy to tell apart because they do not look or act like other cells.
How can the division of cell labor be hazardous to an organism if a particular group of cells are injured or lost?
It can disable or even destroy the body.
Think about what would happen if you lost all of your muscle or brain cells.
__________ are groups of cells that are similar in structure and perform a common or related function.
Tissues
True or False
There are 3 primary tissue types that interweave to form the "fabric" of the body.
False
There are 4 primary tissue types.
What are the 4 primary tissue types?
Epithelial
Connective
Nervous
Muscle
Match The Tissue Types With Their Function
1. Epithelial
2. Connective
3. Nervous
4. Muscle
Covers
Produces movement
Supports
Controls
Epithelial- Covers
Connective- Supports
Muscle- Movement
Nervous- Controls
The Brain, Spinal cord, and Nerves are __________ tissues.
Nervous
Skeletal muscles, Cardiac muscles, and Smooth muscles* are ___________ tissues.
muscle
*The muscles of walls of hollow organs
The lining of digestive track organs, the lining of other hollow organs, and the skin surface are __________ tissues.
Epithelial
Bones, Tendons, and fat are __________ tissues.
Connective
True or False
Tissues are organized into organs. Most organs contain all 4 tissue types, but the tissues' arrangement doesn't matter.
False
Their arrangement determines their structure and what they can do.
What is the study of tissues called?
Histology
__________ allows us to study tissue structure.
Microscopy
Before a specimen can be viewed it must be __________, and then cut into __________ thin enough to transmit light or electrons, and it must be __________ to enhance contrast.
Fixed...
Sections...
Stained
Fixed could also be called __________.
Preserved
Sections could also be called __________.
Slices
What are the 3 steps to take before you can view a specimen with a microscope?
It must be fixed, cut into sections, and then stained.
True or False
Most of the stains used in light microscopy were originally developed by bakers in the mid 1800's to beautifully color food.
False
They were originally developed by clothing manufacturers.
True or False
Many dyes consist of negatively or positively charged molecules that bind to macro-molecules of the opposite charge.
True
The negatively charged molecules are called __________ stains.
Acid
The positively charged molecules are called __________ stains.
Basic
Why do you use different dyes on different parts of a cell or tissue?
Different parts take up different dyes. This helps to distinguish the different anatomical structures.
In Transmission Electron Microscopy (TEM) tissue sections are "stained" with ________ _______ ________.
Heavy Metal Salts
True or False
Heavy Metal Salts deflect electrons in the beam to different extents, providing contrast.
True
Electron-microscope images are in shades of ________.
Grey.
This is because color is a property of light and not of electron waves.
What kind of electron microscopy provides 3D pictures of an unsectioned tissue surface
Scanning Electron Microscopy (SEM)
What are 2 types of electron microscopy?
SEM and TEM
(Scanning Electron Microscopy and
Transmission Electron Microscpy)
Minor distortions (errors) in a specimen's original condition that occur over time are called __________.
Artifacts
True or False
Most Microscopic structures we view are exactly like those of living tissue.
False.
The Artifacts that occur during different procedures alter the specimen.