Chapter 4: Tissue Level of Organization Flashcards
Tissue
a group of cells with specialized activities
Tissues are composed of ___.
Cells and Matrix
The Matrix of tissues can be hard like ___ , semisolid like ___, or liquid like ___.
bone…fat…blood
Cells in most tissues are connected by ___.
junctions
Intracellular Junctions
mechanical connections between cell membranes
Tight Junctions
form a leakproof seal between cells
What is an example of tight junctions?
junctions inside the stomach and bladder to keep materials from leaking out
Adherens Junctions
make an adhesion belt that keeps tissues from separating as they stretch and contract
What is an example of adherens junctions?
cadherin forming the belt-like plaque
Desmosomes
act as spot welds that hook into the cytoplasm
Hemidesmosomes
half welds that join cells to the basement membrane of tissue
Gap Junction
pores that allow ions to pass between cells
What will gap junctions do if the cell gets sick or dies?
it will seal like a hatch to prevent damage to other cells
What are the three primary germ layers?
- Endoderm
- Mesoderm
- Ectoderm
Do epithelial tissues form all three primary germ layers?
YES
What is derived from mesoderm?
Connective tissue and muscle
What tissue develops from ectoderm?
nervous tissue
What are the 4 basic tissue types?
- epithelial
- connective
- muscular
- nervous
Epithelial Tissue
cover body surfaces, form glands and line hollow organs, body cavities, and ducts
What are the three types of epithelial tissue?
- squamous
- cuboidal
- columnar
Connective Tissue
protect, support, and bind organs
4 Examples of Connective Tissue
- fat that stores energy
- red blood cells
- white blood cells
- platelets
Muscular Tissue
generates the physical force needed to make body structures move and generate heat used by the body
Nervous Tissue
detect changes in the body and respond by generating nerve impulses
Epithelium
lines surfaces and forms protective barriers
Epithelium secretes ____, hormones, and other substances.
mucous
True or False: All epithelia have free apical surface and an attached basal surface.
True
The basal layer of the epithelium secretes a ___: the underlying connective tissue secretes a reticular lamina.
basal lamina
What do the basal lamina and reticular lamina form?
basement membrane on which the epithelium sits
Are epithelia named according to cell shape and arrangement of cell layers?
YES
Simple Squamous Epithelium
composed of a single layer of flat cells
Simple Cuboidal Epithelium
composed of a single layer of cube shaped cells
Simple Columnar Epithelium
forms a single layer of column-like cells, cilia, microvilli and mucous
Where is simple squamous epithelium found?
in the air sacs of lungs and the lining of blood vessels, the heart, and capillaries
Where is simple cuboidal epithelium found?
lining of the tubules of the kidneys and many other glands
Goblet Cells
simple columnar cells that can secrete mucous
Stratified Squamous Epithelium
an apical surface that is made up of squamous cells.
True or False: Stratified Squamous Epithelium is composed of many layers.
True
Why do Stratified Squamous Epithelium have many layers?
ideal for protection against strong friction forces
True or False: Connective Tissues are the most abundant and widely distributed tissues in the body.
True
What are 5 function of connective tissue?
- bind tissues together
- support and strengthen tissue
- protect and insulate internal organs
- compartmentalize and transport
- energy reserves and immune responses
What is the most abundant protein in the body, making up about 25% of total protein content, and is the main protein of connective tissue?
Collagen
Connective tissue is usually highly ___ and supplied with many nerves.
vascular
Do cartilage and tendon have blood supply and nerves?
NO
What is the common theme shared between all connective tissues?
They do not have many cells.
Are all connective tissues surrounded by an extracellular matrix?
YES
Extracellular Matrix
non-cellular material located between and around cells
What does extracellular matrix consist of?
protein fibers and ground substance (fluid, semifluid, gelatinous, calcified).
Common Connective Tissue cells are also known as ___.
fibroblasts
Fibroblasts secrete protein fibers and a ___ which varies from one connective tissue to another.
ground substance
What 3 common fibers do connective tissues secrete?
- collagen
- elastin
- reticular
What are three other types of common connective tissue cells?
- adipocytes
- osteocytes
- white blood cells
Adipocytes
store triglycerides
Osteocytes
make bone
What are the 4 main types of white blood cells?
- macrophages
- neutrophils
- eosinophils
- lymphocytes
Macrophages
swallow invaders or debris and can be fixed or wandering
Neutrophils
microphages that are numerous in the blood
Eosinophils
play and important role of inflammation
Lymphocytes
secrete antibody proteins and attack invaders
What are the two main types of connective tissue?
- embryonic connective tissue
- mature connective tissue
What are the two types of embryonic connective tissue?
- mesenchyme
- mucous connective tissue
What are the five types of mature connective tissue?
- loose connective tissue
- dense connective tissue
- cartilage
- bone
- liquid
Mesenchyme
an embryonic connective tissue that gives rise to all other connective tissues
Mucous Connective Tissue (Wharton’s Jelly)
umbilical cord jelly that is rich in stem cells
What are the three types of loose connective tissue?
- areolar
- adipose
- reticular
Areolar Connective Tissue
widely distributed, used to attach skin and underlying tissues, and packs between glands, muscles, and nerves
Adipose Tissue
insulates and serves as padding and energy source
Where is adipose tissue found?
subcutaneous, around organs and joint
Reticular Connective Tissue
forms a scaffolding used by cells of lymphoid tissues such as the spleen and lymph nodes
What are the three types of dense connective tissues?
- dense irregular
- dense regular
- elastic
Dense Irregular Connective Tissue
provides strength when force are pulling from many directions
Dense irregular connective tissue contain ___ and collagen fibers that are randomly arranged.
fibroblasts
Dense Regular Connective Tissue
tendons and ligaments. strong along one axis
Elastic Connective Tisssue
contains fibroblasts and elastic fibers that help stretch
What are the three types of cartilage?
- hyaline
- fibrocartilage
- elastic
Where is Hyaline Cartilage found?
abundant and is found on the ends of long bones and parts of the ribs, nose, trachea, bronchi, and larynx.
Fibrocartilage
contains collagen fibers, is strong and tough
Elastic Cartilage
consists of chondrocytes located in a threadlike network of elastic fibers
Where is elastic cartilage found?
in ear and epiglottis
Where is fibrocartilage found?
inside invertebral disks and knee joints
Bone
calcified intracellular matrix
Blood and Lymph are what type of tissue?
liquid connective tissue
What is meant by the fact that neurons and muscle fibers are electrical excitable cells?
they exhibit the ability to respond to certain stimuli by producing electrical signals (action potentials)
Combining two tissues creates an ___.
organ
Epithelial membranes are the simplest organs in the body, constructed of only ___ and a little bit of connective tissue.
epithelium
Mucous membranes line interior body surfaces open to the outside like ….
- digestive tract
- respiratory tract
- reproductive tract
Serous membrane line some internal surfaces like …
- parietal layer next to body wall
- serous fluid between layers
- visceral layer next to organ
Synovial Membranes
enclose certain joints and are made of connective tissue only
Epithelial Glands
simple organs
Endocrine Glands
glands that secrete their contents directly into the blood
Exocrine Glands
glands that secrete their contents into a lumen or duct
What are 6 secretions of exocrine glands?
- mucus
- sweat
- oil
- earwax
- saliva
- digestive enzymes
What is an example of an exocrine gland?
sweat gland
The criteria for categorizing multicellular glands according to ___ is based on the manner in which the gland secretes its product from inside the cell to the outside environment.
function
What are the three types of exocrine gland secretions?
- merocrine
- apocrine
- holocrine
Merocrine Secretion
the most common secretion and the product is released by exocytosis
Apocrine Secretion
bud their secretions off
What is an example of apocrine gland?
mammary gland
Holocrine Secretion
cells rupture, die, and get replaced
What is an example of holocrine secretions?
sebaceous (skin oil) gland
The ___ cells of an organ that conducts a specific function.
parenchymal
Cells of the ___ are everything that is not the parenchymal cells. Examples: connective tissue, blood vessels, nerves.
stroma
Example of Tissue Repair: The ___ of the heart is cardiac muscle cells. The nerves, intrinsic blood vessels, and connective tissue of the heart comprise the ___.
parenchyma…stroma
When tissue damage is extensive, ___ depends on repair of both parenchymal cells and stroma.
return to homeostasis
What are three processes in tissue repair?
- fibroblasts divide rapidly
- new collagen fibers are manufactured
- new blood capillaries supply materials for healing
All of the tissue repair processes create an actively growing connective tissue called ___.
granulation tissue
True or False: Tissue heals faster in young adults.
True
True or False: Surgery of a fetus leaves scars.
False
True or False: Young tissues have a better nutritional state, blood supply, and higher metabolic rate.
True
True or False: Extracellular components do not change with age.
False
True or False: Changes in the body’s glucose, collagen, and elastic fibers do not contribute to the aging process.
False
