Ch.1 Continued Flashcards
Cell functions include:
- movement of substances across the cell membrane
- cell division to make new cells
- protein synthesis
Movement of substances from a region of high concentration to a region of low concentration. Can also occur across a membrane
Diffusion
Oxygen and carbon dioxide can diffuse through cell membranes. Diffusion can occur across a membrane as long as the membrane is permeable to the substance involved.
Oxygen and carbon dioxide are able to diffuse through the cell membrane. When Carbon dioxide builds up in the capillaries to concentration that is higher in the lungs, the CO2 diffuses where to be exhaled?
Similarly, when the level of oxygen in the capillaries is lower than the oxygen in the lungs, oxygen diffuses into where for distribution into the body cells?
So, this way, the gases are exchanged between the air and the blood in the lungs, and between the blood and cells of the various tissues.
- The CO2 diffuses into the lungs to be exhaled
- Oxygen diffuses into the capillaries for it to b distributed through the body cells
Diffusion of water from a selectively permeable membrane. Movement from low solute concentration to a region of high solute concentration.
Osmosis
Molecular movement down a concentration gradient
simple diffusion
When red blood cells (RBC’s) are placed in the following (isotonic, hypertonic, and hypotonic) solutions what will happen?
Isotonic: RBC’s will stay the same
Hypertonic: water will leave the RBC’s and enter the surrounding fluid in the environment causing the cell to shrink or crenate
Hypotonic: water will enter the RBC’s making the cell swell and even possibly rupture (called hemolysis)
If a red blood cell, which contains 5% glucose, is placed in a container of 5% glucose solution, how will water move in both directions at the same rate because?
The glucose concentration inside and outside the cell are the same (isotonic)
When a red blood cell is placed in a 10% glucose solution, water will leave the cell (where there are more water molecules) and enter the surrounding fluid (where there are fewer water molecules). When fluid leaves the cells, they will what?
P.S. The 10% glucose solution has a greater solute concentration than the cell.
The cells will shrink (hypertonic)
When a red blood cell is placed in distilled water (that has a low solute concentration than the cell), water will enter or exit the cell when there are more water molecules outside the cell than the inside?
enter the cell making it a hypotonic solution
As water enters the cell, it will swell because of the increased volume. If enough water goes into the cell making it rupture it is known as what?
When this happens specifically to a red blood cell it is called?
lysis… to a red blood cell–> hemolysis
Pressure pushes the particles through a membrane. Movement of solvent using hydrostatic pressure; requires membrane filter.
Filtration
What is this an example of?
Blood is filtered through membranes in the kidney as the initial step of urine formation.
Filtration
What happens when blood is filtered through membranes in the kidney as the initial step of urine formation? (2)
-water and small molecules pass through filtration membrane
- blood cells remain in the blood
Process that moves substances across or through a membrane and does not require cellular energy.
What is this and what are the 3 things involved in this?
Passive transport:
- Simple diffusion
- Osmosis
- Filtration
Maintains concentration gradients. Moves molecules “uphill” from an area of low concentration to high concentration. Cellular energy is required in the form of ATP. Uses carrier molecules. If ATP is not available, this ceases immediately. Some substances are presented in significantly higher concentrations on one side of the membrane than on the other.
Active transport
This is an example of what?
Sodium ions more concentrated inside or outside the plasm membrane? Potassium ions concentration is higher inside or outside the cell?
Active transport:
sodium ions: outside
potassium ions: inside
Active transport is also used to transport amino acids and glucose from what organ into the blood?
small intestine
Formation of vesicles to transfer particles and droplets from outside to inside the cell. Material is too large to enter the cell by diffusion or active transport. Requires ATP energy.
Endocytosis
Endocytosis has two types:
phagocytosis and pinocytosis
white blood cells that engulf and destroy bacteria
phagocytes
“cell eating”. Cell membrane engulfs a particle to form a vesicle in the cytoplasm. Lysosomes fuse with the vesicle and the enzymes digest the particle
phagocytosis
“cell drinking”. important in cells that function in absorption.
pinocytosis
Difference between pinocytosis from phagocytosis:
- vesicles that are formed are much smaller and their contents are fluid
Secretory products are packaged into vesicles by the Golgi apparatus and released from the cell. The secretory vesicle moves to the cell membrane, where the vesicle membrane fuses with the cell membrane, and the contents are discharged to the outside of the cell.
Exocytosis
What are 2 examples of exocytosis?
- secretion of digestive enzymes from the pancreas
- secretion of milk from mammary glands
The process by which new cells ae formed for growth, repair, and replacement in the body.
Cell Division
More than 2 million of what are worn out and replaced every second of every day?
red blood cells
What cells are continually sloughed off the body’s surface and must be replaced?
skin cells
What lining is replaced every few days?
lining of the stomach
Somatic cells divide to form two new “daughter cells”, each identical to the parent cell.
Mitosis
Humans have how many pairs of chromosomes? How many total chromosomes?
23 pairs, 46 in total
What are the stages of mitosis?
1.) Interphase
2.) Prophase
3.) Metaphase
4.) Anaphase
5.) Telophase
period between active cell divisions
Interphase
chromatin shortens to form chromosomes
Prophase
chromosomes align along the center of the cell
Metaphase
chromosomes migrate to opposite ends of the cell
Anaphase
Cell divides to begin to form two daughter cells that are exact copies of the parent cell
Telophase
Division of the cell at the end of mitosis to form two separate daughter cells.
Cytokinesis
Only occur in reproductive cells (gametes)–eggs or sperm. Gametes only have 23 chromosomes. When fertilization takes place: resulting cell will have 46 chromosomes= 23 from egg and 23 from sperm
Meiosis
DNA in the nucleus directs the synthesis of the protein in the cytoplasm to determine: (2)
- Determine the structural and functional characteristics of an individual
- The purpose of DNA replication is to produce genes in the offspring that are exactly the same as those in the parents.
Portion of a DNA molecule that contains the genetic information for making on particular protein molecule.
Gene
Microscopic study of tissues
Histology
Nonliving material that fills the space between cells. Contains salts and fibers that are unique to a specific tissue and give the tissue distinctive characteristics
Intercellular matrix
Where is epithelial tissue located?
- all body surfaces
- line body cavities and hollow organs
- major tissue in glands
Function of Epithelial Tissue:
- protection, secretion, absorption, excretion, filtration, diffusion, and sensory reception
Is avascular (without blood vessels) so they must receive nutrients and oxygen supply by diffusion. They regenerate and reproduce quickly
Epithelial tissue
flat and nuclei are usually broad and thin
squamous cells
cubelike, as tall as they are wide, and nuclei are spherical and centrally located
cuboidal cells
cells are tall and narrow, resembling columns and nuclei are usually in the lower part of the cell near the basement membrane
columnar cells
attaches epithelial tissue to underlying connective tissue
basement membrane
have only 1 layer of cells
simple
have multiple layers
stratified
Consists of a single layer of thin, flat cells that fit closely together with little intercellular matrix. Because it’s so thin, it is well suited for areas in which diffusion and filtration take place.
simple squamous epithelium
Where is the simple squamous epithelium found in?
- alveoli of the lungs
- kidney, where blood is filtered
- capillary walls
True or False?
Capillary walls are made up of simple squamous epithelium.
True
Consists of a single layer of cube-shaped cells. These cells have more volume than squamous cells and also have more organelles.
Simple cuboidal epithelium
Where are simple cuboidal epithelium found in?
- covering of the ovary
- lining of kidney tubules
- glands (thyroid, pancreas, and salivary)
A single layer of cells that are taller than they are wide. Tal and thick
simple columnar epithelium
Where are simple columnar epithelium found in?
- lining of stomach and intestines
- where it secretes digestive enzymes and absorbs nutrients
What epithelium is tall and thick and because of this, it offers some protection to underlying tissues?
simple columnar epithelium
Small projections of the cell membrane where absorption is of primarily importance. Increase the surface area of absorption
microvilli
Frequently interspersed among simple columnar cells. Flask or goblet-shaped that secrete mucus onto the free surface of the tissue. Cilia may present to move secretions along the surface.
Goblet cells
Appears to have multiple layers, but it really does not. Cells are not at the same height; some cells are short and some are tall. Nuclei are at different levels. All cells are attached to the basement membrane but not all of them reach to the free surface of the tissue.
Pseudostratified Columnar epithelium
Where is pseudostratified epithelium located?
- Lines the portions of the respiratory tract ( in which the mucus, produced by the goblet cells, traps dust particles and is then moved upward by the cilia)
- Lines some of the tubes of the male reproductive system (cilia can help propel the sperm from one region to another)
What is the most widespread epithelium and is thick because it consists of many layers of cells?
Stratified Squamous Epithelium
The cell son the bottom layer, next to the basement cell membrane, are usually cuboidal or columnar, and these are the cells that undergo mitosis. As the cells are pushed upward towards the surface, they become thinner, so the surface cells are are squamous. As the cells are pushed away from the basement membrane, it is more difficult for them to receive oxygen and nutrients from underlying connective tissue, and the cells die.
As cells on the surface are damaged and die they are sloughed off and are replaced by cells from the deeper layer.
Stratified squamous epithelium
Where is the stratified squamous epithelium located?
- Because it is thick, it is found in areas in which protection is a primary function.
- Forms the outer layer of the skin
Consists of several layers but can be stretched in response to tension.
Transitional Epithelium
Where is the transitional epithelium located?
- lining of the urinary bladder…when the bladder is empty and contracted, the epithelial lining has several layers of cuboidal cells. As the bladder fills and is distended or stretched, the cells become thinner and the number of layers decrease.
Consists of cells that produce and secrete substances. Lies deep to the epithelia that covers and lines part of the body.
Glandular Epithelium
What two things are part of the glandular epithelium?
exocrine and endocrine glands
secretes its products onto a free surface via a duct. Ex–> sebaceous glands, mammary, and salivary glands
exocrine gland
secretes its products directly into the blood
endocrine gland
Found throughout the body. Examples are cartilage, adipose tissue, and bone
Connective tissue
What are the functions of connective tissue?
- binds structures together
- forms framework and support for organs and the body as a whole
- stores fat and transport substances
- help repair tissue damage
What are the 2 fibers found in the connective tissue?
collagenous and elastic fibers
composed of the protein collagen. Strong and flexible. Can withstand considerable pulling force.
collagenous fibers
Where are collagenous fibers found in?
in ligaments and tendons
Composed of the protein elastin.
elastic fibers
Where are elastic fibers found?
where structures are stretched and released such as the vocal cords
What cells are found in connective tissue?
fibroblasts, macrophages, and mast cells
phagocytic cells that clean up cellular debris and foreign particles
macrophages
contain heparin and histamine to produce inflammation
mast cells
Connective tissue cell that produce fibers
fibroblasts
Areolar connective tissue. One of the most widely distributed tissues in the body.
Loose connective tissue
What is the function of loose connective tissue?
- attaches the skin to underlying tissues
- fills the spaces between muscles
- blood vessels in here supply nutrients to the epithelium
Very little intercellular matrix. Cells accumulates fat droplets. Cytoplasm and nucleus are pushed off to one side. Cells swell and become closely packed together.
Adipose tissue
Function of Adipose tissue:
- forms a protective cushion around he kidneys, heart, eyeballs, and joints
- provides insulation for heat
- energy storage material for excess calories
Closely packed bundles of collagenous fibers in the intercellular matrix. Makes up what 2 things?
Dense fibrous connective tissue.
- tendons and ligaments
What tissue has poor blood supply making it a slow healing tissue?
Dense connective tissue
connect muscles to bones
tendons
connects bones to bone
ligaments
Closely packed elastic fibers in the intercellular matrix.
Elastic Connective Tissue
What does elastic connective tissue make up?
vocal cords and ligaments that connect adjacent vertebrae
Cartilage has an abundant matrix that contains:
- chondrin: a protein
- chondrocytes (cartilage cells) located in spaces called lacunae
- perichondrium: dense fibrous connective tissue that surrounds the cartilage
cartilage cells located in spaces called lacunae
chondrocytes
dense fibrous connective tissue that surrounds the cartilage
perichondrium
Functions of Cartilage: (3)
- protects underlying tissues
- supports other structures
- provides a framework for attachments
Most common type of cartilage. Found on the ends of LONG bones. Most of the fetal skeleton is formed of this cartilage before its replaced by bone.
hyaline cartilage
has an abundance of strong collagenous fibers found in intervertebral disks, symphysis pubis, and between the bones in the knee joint.
Fibrocartilage
Has numerous elastic fibers. Found in the external ear, epiglottis, and auditory tubes.
Elastic cartilage
Most rigid of all connective tissue. Have what fibers that give strength to this in the process? What gives hardness to this?
Bone
- collagenous fibers
- calcium
What are the functions of bone? (5)
- form framework of the body
- helps protect underlying tissues
- serves as attachment for muscles
- uses mechanical levers to produce movement
- contributes to the formation of blood cells (bone marrow)
Haversian systems. Packed together to form the substance of compact bone.
Osteons
Haversian canal. Center of the osteon and contains a blood vessel.
osteonic canal
Concentric rings in the matric around the canal
lamellae
bone cells. located in lacunae between the lamellae
osteocytes
tiny tubes from which processes from the bone cells extend through tiny tubes in the matrix to other cells or to osteonic canals. Provides a blood supply for bones.
canaliculi
The only connective tissue that has liquid matrix.
Blood
What is the function of blood?
Transport substances through the body
RBC’s that transport oxygen from the lungs to the tissues
Erythrocytes
WBC’s that fight disease
Leukocytes
platelets that initiate the blood clotting process
Thrombocytes
makes up the liquid matrix
plasma
Thin sheets of tissue that: cover the body, line body cavities, covers organs within the cavities, and lines the cavities in hollow organs
Body Membranes
Epithelial membranes that line body cavities that open to the outside. Secrete mucous for lubrication and protection
Mucous Membranes
Where are mucous membranes located?
digestive, respiratory, urinary, and reproductive tracts
Line body cavities that do not open directly to the outside. Consists of a thin layer of loose connective tissue covered by simple squamous epithelium. Covered by a thin layer of serous fluid. It lubricates the membrane and reduces friction and abrasion when organs move against the cavity wall
Serous Membranes
Lines the thoracic cavity and covers the lungs
pleura
lines the pericardial cavity and covers the heart
pericardium
lines the abdominopelvic cavity
peritoneum
Composed of cells that have the special ability to shorten or contract. Well supplied with blood vessels.
Muscle tissue
The skeletal muscle constitutes about how much of an individuals body weight?
40%
Long and cylindric with many nuclei (multinucleated) and have a striated appearance
skeletal muscle fibers
Cause body movements when they contract and is under voluntary control
Skeletal muscle
Found in the walls of hollow body organs. Stomach, intestine, urinary bladder, uterus, blood vessels. Spindle-shaped and tapered at the ends. Has one nucleus
Smooth Muscle
Propels substances through the organ by contracting and relaxing and is under involuntary control
Smooth muscle
Found only in the wall of the heart. Cylindric and appears striated. One nucleus per cell. Responsible for pumping blood through the heart and blood vessels. Under involuntary control
Cardiac muscle
Found in the brain, spinal cord, and nerves. Responsible for coordinating and controlling many body cavities.
Nervous tissue
Cells that support the activities of the neuron.
Neuroglia
bind neurons together and insulate the neurons
glial cells
cells in nervous tissue that generate and conduct impulses
neurons
main part of the nerve cell
nerve cell body
tree like; extensions or processes of the cytoplasm that carry impulses o the cell body. Carry impulses to cell body .
Dendrites
Carry impulses away from cell body.
Axons
Connective tissue membranes. Secretes synovial fluid into the joint cavity. Lines the cavities of freely moveable joints (shoulder, elbow, knee)
Synovial Membrane
lubricates the cartilage on the ends of the bone (enabling free movement without friction)
synovial fluid
Connective tissue coverings around the brain and spinal cord. Provides protection for brain and spinal cord.
Meninges
Tough outermost layer of the meninges.
Dura mater
middle layer of the meninges.
Arachnoid
Delicate innermost layer of meninges. Closely adheres to the surface of the brain and spinal cord.
Pia mater
inflammation of the meninges
Meningitis
