Unit 2 - Cells, Tissues And Integumentary System Flashcards
List the general functions of the plasma membrane
PRSS
Physical isolation.
Regulation of exchange with the environment.
Sensitivity to the environment.
Structure support.
Identify the components that allow the plasma membrane to carry out its functions
LPC
Lipids (phospholipids and cholesterol)
Proteins
Carbonhydrates
What component of the plasma membrane is primarily responsible for the membrane to form a physical barrier between the cells internal and external environment?
Phospholipid bilayer (forms a physical barrier between the internal and external environment)
Which type of integral protein allows water, ions, and water-soluble solutes to pass through the plasma membrane?
Channel proteins (Spans the membrane and makes hydrophilic tunnels across it, allowing its target molecules to pass through it by diffusion)
Explain the difference between the cytoplasm and the cytosol
Cytosol is the fluid contained in the cell cytoplasm.
Cytoplasm is the entire content within the cell membrane.
What are the major differences between cytosol and extracellular fluid?
In contrast to extracellular fluid, cytosol has a high concentration of potassium ions and a low concentrations of sodium ions.
Identify the nonmembranous organelles, and cite a function of each.
CCRP
Cytoskeleton (serves as the cells skeleton)
Centrosome and centrioles
(serves to organise the microtubules and provide a structure to the cell
Ribosomes (serves by making proteins)
Proteasomes (degrades unneeded or damaged proteins by proteolysis)
Describe the content and structure of the nucleus
Nuclear envelope
Nucleoplasm
Chromatin
Nucleos
The nuclear membrane forms an envelope like structure around the nuclear contents and is commonly known as a nuclear envelope
What is a gene?
The basic physical and functional unit of heredity
Define gene activation
The process of activation of a gene so that it is expressed at a particular time.
Describe transcription and translation
Transcription is the process by which DNA is copied to RNA.
Translation is the process where RNA is used to produce proteins.
What processes would be affected by the lack of the enzyme RNA polymerase.
The lack of polymerase will cause one of the subunits of RNA to not be transcribed from DNA
What is meant by the term selectively permeable when referring to a plasma membrane?
It’s the ability to differentiate between different types of molecules, only allowing some through and blocking others
Define diffusion
The spreading of something more widely from high concentration region to low concentrations region
List five factors the influence the diffusion of substances in the body.
DITCE
Distance Ion and molecule size Temperature Concentration gradient Electrical forces
How would a decrease in the concentration of oxygen in the lungs affect the diffusion of oxygen in blood?
Diffusion into the cells increase
Define osmosis.
The spontaneous passage or diffusion of water or other solvents through a semipermeable membrane
What effect would such a solution have on the cells lining the nasal cavity, and why?
Cells would lose water, due to the salt solution being a hypertonic solution
Describe the process of carrier-mediated transport
It combines a chemical reaction with a diffusion process.
The concentration of hydrogen (H+) in the stomach contents during digestion rises to a higher level than in the cells lining the stomach, which transport process must be operating?
An active transport process
Describe endocytosis
A process by which cells absorb external material by engulfing it with the cell membrane
Describe exocytosis
The process by which cells move materials from within the cell into extracellular fluid
What is the process called whereby certain types of white blood cells engulf bacteria
Phagocytosis
What is the membrane potential of a cell, and in what is it express?
Electric potential differences across the interior and exterior of the cell
80mv to 40mv
If the plasma membrane of a cell were freely permeable to sodium ions, how would the membrane potential be affected?
The membrane potential would reach an equilibrium state
Give the biological term for cellular reproduction and cellular deat
Cellular reproduction - mitosis and meiosis
Cellular death - apoptosis
What enzymes must be present for DNA replication to proceed normally?
PPHLT
DNA polymerase DNA primase DNA helicase DNA ligase DNA Topoisomerase
Describe interphase, and identify it’s stages
It’s the phase in a cells cycle in which the cells spends most of its life
G1 phase (cell growth) S phase (DNA synthesis) G2 phase (cell growth)
A cell is actively manufacturing enough organelles to serve two functional cells, this cell is probably in what phase of its life cycle?
G1 phase of interphase
Define mitosis, and list its four stages
Mitosis is the process where a single cell divides into two identical daughter cells
PMAT
Prophase
Metaphase
Anaphase
Telophase
What would happen if spindle fibers failed to form in a cell during mitosis?
No disjunction of chromosomes will take place
Define growth factor, and identify several growth factors that affect cell division?
A substance, like vitamins or hormones, which is required for the stimulation of growth in living cells.
NGCS
Nutrients
Genetics
Chemicals
Stress
An illness characterized by mutations that disrupt normal control mechanism and produce potentially malignant cells is termed…
Carcinogenesis (oncogenesis or tumorigenesis)
Define metastasis
The development of secondary malignant growths at a distance from a primary site of cancer
Define cellular differentiation
Cellular differentiation is the process in which a stem cell alters from one type to a differentiated one
Define histology
The study of the microscopic structure of tissues
Identify to four major types of tissue in the body
CEMN
Connective tissue
Epithelial tissue
Muscle tissue
Nervous tissue
Identify four essential functions of epithelial tissue
Protection from the environment
Coverage
Secretion
Excretion
List five important characteristics of epithelial tissue
CPAVR
Cellularity Polarity Attachment Vascularity Regeneration
What is the probable functions of an epithelium whose cells bear microvilli?
Absorption or secretion
Identify the various types of epithelial cell junctions
OADG
Occluding junction
Adhering junction
Desmosomes
Gap junction
What is the functional significance of a gap junction?
Allows the exchange of ions, second messengers, and small metabolites between adjacent cells
Identify the three cell shapes characteristic of epithelial cells.
SCC
Squamous
Cuboidal
Columnar.
When classifying epithelial tissue, one with a single layer of cells is called , whereas one with multiple layers of cells is called
Simple …
Stratified …
Viewed with a light microscope, a tissue appears as a simple squamous epithelium. Can this be a sample of the skin surface? Why or why not?
No, this is not a sample of the skin surface. A simple squamous epithelium does not provide enough protection against infection, abrasion, or dehydration. The skin surface has a stratified squamous epithelium.
Why do the pharynx, esophagus, anus, and vagina have a similar stratified epithelial organization?
All of these regions are subject to mechanical trauma and abrasion - by food (pharynx and esophagus), by feces (anus), and by intercourse or childbirth (vagina).
Name the two primary types of glandular epithelia
The two primary types of glandular epithelia are endocrine glands and exocrine glands.
The secretory cells of sebaceous glands fill with vesicles and then rupture, releasing their contents. Which method of secretion is this?
Sebaceous glands exhibit holocrine secretion.
Which type of gland releases its secretions directly into the interstitial fluid?
This gland is an endocrine gland.
Identify several functions of connective tissues.
- defending the body from invading microorganisms
- establishing a structural framework for the body
- protecting delicate organs
- storing energy reserves
- supporting, surrounding, and interconnecting other types of tissue
- transporting fluids and other dissolved material
List the three categories of connective tissues.
The three categories of connective tissue are connective tissue proper, fluid connective tissues, and supporting connective tissues.
Identify the cells found in connective tissue proper
AFFLMMMMM
Adipocytes Fibroblasts Fibrocytes Lymphocytes Macrophages Mast cells Melanocytes Mesenchymal cells Microphages.
Lack of vitamin C in the diet interferes with the ability of fibroblasts to produce collagen. What effect might this interference have on connective tissue?
weak and prone to damage
Lack of vitamin C in the diet interferes with the ability of fibroblasts to produce collagen. What effect might this interference have on connective tissue?
weak and prone to damage
Many allergy sufferers take antihistamines to relieve their allergy symptoms. Which cells produce the substance that this medication blocks?
Mast cells and basophils produce the molecule histamine
Which type of connective tissue contains primarily triglycerides?
adipose (fat) tissue.
Name the three layers of fascia and their types of connective tissue
SDS
Superficial fascia (areolar and adipose tissue) Deep fascia (dense irregular connective tissue) Subserous fascia (areolar tissue).
Which two types of connective tissue have a fluid matrix?
blood and lymph
Describe the recirculation of fluid in the body.
F
Identify the two types of supporting connective tissue
bone and cartilage.
Why does bone heal faster than cartilage?
bone has a direct blood supply (highly vascular) which is necessary for proper, rapid healing to occur.
If a person has a herniated intervertebral disc,
characterized by displacement of the pad of cartilage between the vertebrae, which type of cartilage has been damaged?
fibrocartilage
Identify the four types of tissue membranes found in the body
CMSS
Cutaneous membrane
Mucous membranes
Serous membranes
Synovial membranes
Which cavities in the body are lined by serous
membranes?
Pleura
Peritoneal
Pericardial cavities
Which type of tissue membrane typically lines body passageways (such as the urinary tract) that open to the exterior?
Mucous membrane
Identify the three types of muscle tissue in the body
cardiac, smooth, and skeletal
Which type of muscle tissue has small, tapering cells with single nuclei and no obvious striations?
smooth muscle
If skeletal muscle cells in adults are incapable of dividing, how is skeletal muscle repaired?
Skeletal muscles are repaired by the division and fusion of myosatellite cells which are mesenchymal cells that persist in the adult skeletal muscle tissue
Identify some age-related factors that affect tissue repair and structure
F
What would account for the observed increase in cancer rates with age?
F
Identify the two phases in the response to tissue injury
Inflammatory response
Remodeling response
List the four common signs of inflammation
Redness (Latin rubor)
Heat (calor)
Swelling (tumor)
Pain (dolor)
Identify several functions of connective tissues
binding and supporting protecting insulating Storing reserve fuel Transporting substances within the body
List the three categories of connective tissues
loose connective tissue
dense connective tissue
specialized connective tissue.
Identify the cells found in connective tissue proper
fibroblasts mast cells plasma cells macrophages adipocytes Leukocytes.
A tissue contains irregularly shaped cells with many fibrous projections, some several centimeters long. These are probably which type of cell?
Neurons
Identify the layers of the epidermis
stratum basale (the deepest portion of the epidermis)
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum (the most superficial portion of the epidermis)
Dandruff is caused by excessive shedding of cells from the outer layer of skin on the scalp. So dandruff is composed of cells from which epidermal layer?
Stratum corneum
A splinter that penetrates to the third layer of the epidermis of the palm is lodged in which layer?
stratum granulosum
Why does taking a bath cause wrinkly fingertips and toes?
your nervous system sends a message to your blood vessels to shrink.
Some criminals sand the tips of their fingers so as not to leave recognizable fingerprints. Would this practice permanently remove fingerprints? Why or why not?
Sanding the tips of the fingers will not permanently remove fingerprints. The ridges of the fingerprints are formed in layers of the skin that are constantly regenerated, so these ridges will eventually reappear.
Name the sources of epidermal growth factor in the body.
urine saliva milk tears blood plasma
Identify some roles of epidermal growth factor related to the epidermis.
Epidermal growth factor (EGF) promotes the divisions of germinative cells in the stratum germinativum and stratum spinosum, accelerates the production of keratin in differentiating keratinocytes, stimulates epidermal development and epidermal repair after injury and stimulates synthetic activity and secretion by epithelial glands.
Describe the location of the dermis
The dermis (a connective tissue layer) lies between the epidermis and the hypodermis.
Where are the capillaries and sensory nerve fibers that supply the epidermis located?
The capillaries and sensory neurons that supply the epidermis are located in the papillary layer of the dermis.
What accounts for the ability of the dermis to undergo repeated stretching?
The presence of elastic fibers and the resilience of skin turgor allow the dermis to undergo repeated cycles of stretching and recoil (returning to its original shape).
List the two terms for the tissue that connects the dermis
The tissue that connects the dermis to underlying tissues is the hypodermis or subcutaneous layer.
Describe the subcutaneous layer
the deepest layer of your skin.
Identify several functions of subcutaneous fat.
It’s the one way that your body stores energy.
It functions as a padding to protect your muscles and bones from the impact of hits or falls.
It serves as a passageway for nerves and blood vessels between your skin and your muscles.
It insulates your body, helping it regulate temperature
Name the two major pigments in the epidermis
carotene( an orange-yellow pigment) and melanin ( a brown, yellow-brown, or black pigment).
Why does exposure to sunlight darken skin?
sunlight causes the skin to produce more melanin and darken.
Why does the skin of a fair-skinned person appear red during exercise in hot weather?
When skin gets warm, arriving oxgenated blood is diverted to the superficial dermis for the purpose of eliminating heat
Explain the relationship between sunlight exposure and vitamin D3 synthesis
During exposure to sunlight 7-dehydrocholesterol in the skin absorbs UV B radiation and is converted to previtamin D3 which in turn isomerizes into vitamin D3
In some cultures, women must be covered completely, except for their eyes, when they go out in public. Explain why these women may develop bone problems later in life.
The hormone calcitriol is essential for the absorption of calcium and phosphorus, which are elements needed to form strong bones and teeth.
Describe a typical strand of hair
A typical hair isa keratinous strand produced by basal (germinative) cells within a hair follicle
What happens when the arrector pili muscle contracts?
it causes the hair to stand erect, and a “goosebump” forms on the skin.
Once a burn on the forearm that destroys the epidermis and extensive areas of the deep dermis heals, will hair grow again in the affected area?
even though hair is a derivative of the epidermis, the hair follicles are in the dermis. Where the epidermis and deep dermis are destroyed, new hair will not grow.
Identify two types of exocrine glands found in the skin.
2 types of exocrine glands found in the skin are sebaceous glands and sweat glands
What are the functions of sebaceous secretions?
produce and secrete sebum
Deodorants are used to mask the effects of secretions from which type of skin gland?
apocrine sweat gland
Which type of skin gland is most affected by the hormonal changes that occur during puberty?
Apocrine sweat glands
What substance makes fingernails hard?
keratin
What term is used to describe the thickened stratum corneum underlying the free edge of a nail?
the hyponychium
Where does nail growth occur?
the nail’s base
What term describes the combination of fibrin clots, fibroblasts, and the extensive network of capillaries in healing tissue?
granulation tissue
Why can skin regenerate effectively even after
considerable damage?
stem cells persist in both the epithelial and connective tissue components of skin
