When Cancer Cells Express The Wrong Gene

cancer cells
An Ovarian Teratoma: The photo shows a type of tumor that includes teeth at the bottom part of the ovary. This ovarian tumor expressed the wrong gene which results in the formation of teeth at the wrong location. Source: https://commons.wikimedia.org/wiki/File:Ovarian_teratoma.jpg

When Cancer Cells Express The Wrong Gene

An organism is formed based from an architectural blueprint called DNA. In eukaryotes including human cell, the nucleus holds the DNA. Humans contain 46 chromosomes and for each chromosome, DNA is organized into a strand. Each shorter segment of the DNA strand is called genes. This is analogous to organizing a long paragraph into a different clear sentences. Each gene is an instruction to make a protein. Analogically speaking, DNA in eukaryotic cells are like the apps (application software) in mobile phone. If you want to know the current date, you would only access the calendar app and not run the other programs. The same idea applies in eukaryotic DNA. A cell does not express all the gene stored in the nucleus and only express gene that are needed depending on the type of cell. For example, each cell in the human body regardless of where it is located contains the gene to make the hair, skin, teeth, liver, and ovary, but these genes are turned off in the stomach cells. If genes for making the teeth were turned on in the stomach cells, you will have teeth forming in the stomach.


Blankenship-Williams, L. (2015). What You Really Need To Know Before Anatomy, Physiology, and Microbiology. Carbohydrates and Nucleic Acids. Accessed November 18, 2019. https://www.amazon.com/really-before-Anatomy-Physiology-Microbiology/dp/0692481923

What Are Common Anatomical Sites For Pressure Ulcers?

What Are Common Sites For Pressure Ulcers?

Pressure ulcers are commonly known as bedsores which is caused by prolonged pressure on the skin and damages the underlying tissues. Most pressure ulcers develop on the skin covering a bony part of the body. For premed and pre-nursing students, the following are the bony areas of the body that pressure ulcers are most likely to develop.

  • occipital bone
  • spine of the scapula
  • olecranon process
  • sacrum
  • coccyx
  • ischial tuberosity
  • greater trochanter
  • calcaneus
  • lateral and medial malleolus
  • medial condyle of tibia

What Are The Compositions of Human Semen?

What Are The Compositions of Human Semen?

The main component of semen are the sperms and about 80 million spermatozoa can be found in a milliliter of semen. Some properties of semen are as follows:

Color: Opalescent White

pH: 7.35 to 7.50

Specific Gravity: 1.028

There are many other components of semen which can be classified according to its site of origin: seminal vesicle, prostate, and bulbourethral glands. Seminal vesicle adds components to semen such as fructose, phosphorycholine ergothioneine, ascorbic acid, flavins, prostaglandins, and bicarbonate. Prostate gland secretes prostatic fluid, spermine, citric acid, cholesterol, phospholipids, fibrinolysin, fibrinogenase, zinc acid, and phosphatease. Bulbourethral glands secrete clear mucus during sexual arousal.


Feingold KR, Anawalt B, Boyce A, et al. The Composition Of Human Semen. https://www.ncbi.nlm.nih.gov/books/NBK279008/table/benign-prstate-dsrdr.colourwhit

What is Xenotransplantation?

Image by Elionas2 from Pixabay

What is Xenotransplantation?

Most of us know about human organ transplant. A surgeon replaces a failing organ with a healthy organ from another person. Sounds easy enough but the problem is that, human organs are always out of stock. So we turn our need to the other species in the evolutionary tree.

Xenotransplantation, as defined by the World Health Organization, is a living cell, tissue, or organ transplant between two different species such as pigs to humans. It was derived from the Greek word xenos- which means “foreign.” Xenotransplantion dates back more than 100 years ago. During the early 1900, the first few attempts of xenotransplant use organs from pig, goat, sheep, and monkey but were unsuccessful and patients only last for several hours or days. In 1963, chimpanzee kidney transplants were performed to 13 patients and only one survived for 9 months. A modified pig liver was used temporarily in 1997 to keep a patient alive until a suitable liver becomes available. Also in 1997, xenotransplantation was banned worldwide due to a high risk of infectious disease from animals but was lifted later on and today, clinical trials for xenotransplantation continues.

Xenotransplantation is important because it can potentially benefit thousands of patients. It can provide unlimited supply of cells, tissues, and organs. It can replace diseased organs such as heart, lungs, liver, pancreas, and kidney. It can replace damaged cells from diabetes, Alzheimer’s, and Parkinson’s disease. It can be used for skin grafts, cornea transplant, or bone transplant. It can provide temporary external organ function to patient with organ failure.

One problem that can be solved with xenotransplantation is the shortage of human organs. According to DonorOrgan.gov, there are 113,000+ patients awaiting organ transplant in the United States last year. From the waiting list, only 29% received organ transplant. On average, 20 people die everyday waiting for a donor. The waiting list will continue to grow as one person is added to the list every 10 minutes.

Currently, the best candidates for xenotransplantation donor are the pigs. Chimpanzees are thought to be the best option since they are closely related to humans. Chimpanzee organs are similar in size and there blood type is compatible to humans. The only problem is that Chimpanzees are endangered species. Baboons were also considered as organ donors but they have smaller body size, infrequent type O blood (the universal donor), and they do not produce a lot of offspring. The major problem in using non-human primates is the risk of disease transmission because they are so closely related to humans according to the Phylogenetic tree. Pigs on the other hand are distant to humans which lowers the risk of disease transmission. As we know, pigs are readily available and there organs are comparable in size. There is less likely for a new infectious agent to develop because pigs are always in close contact with humans through domestication.

The development of xenotransplantation comes with barriers, issues, and concerns. The human immune system itself is the major obstacle for the success of xenotransplantation. Normally, the inside of our body destroys anything that is foreign. Since animal organs are foreign, the human immune system will attack the transplanted organ which leads to fatal infection. Extensive research is still needed on whether animal organs can replace the physiological function of human organs. Pigs can only live for roughly 15 years and we do not know if there organs can last longer than that. Human hormones and proteins are different from pigs and can cause malfunction of regulatory processes. Pigs have a higher body temperature than humans and the implications for the difference is still unknown. Lastly, xenotransplantation is a very controversial procedure since the beginning and many animal rights group opposed killing animals to harvest their organs for human use.

In summary, no xenotransplantation has been successful for the last 100 years due to a number of obstacles and the development is only driven by the number of demand for human organs far exceeds the supply, but if successful, the benefits and resources are considerable. Since human organs are always out of stock, state government are already stepping in by considering a policy that makes everyone an organ donor by default.


Health Matters. (2017, August 9). How Xenostransplantation Works. Retrieved March 1, 2019

Science Learning Hub. (2011, December 7). Xenotransplantation – Introduction. Retrieved March 1, 2019

Medscape. (2018, November 13). Xenotransplantation. Retrieved March 1, 2019

Biotechnology Innovation Organization. Xenotransplantation: The Benefits and Risks of Special Organ Transplantation. Retrieved March 1, 2019 https://www.bio.org/articles/xenotransplantation-benefits-and-risks-special-organ-transplantation

World Health Organization. (2005, May 2). Xenotransplantation. Retrieved March 1, 2019

Organ Donor. (2018, October 1). Organ Donor Statistics. Retreived March 1, 2019

PETA Media Center: Factsheet: Xenotransplantation (2010, June 26) Peta.org. Retrieved March 1, 2019

U.S. Food and Drug Administration. (2018, May 2). Xenotransplantation. Retrieved March 1, 2019 https://www.fda.gov/biologicsbloodvaccines/xenotransplantation/default.htm

Common Human Anatomy and Physiology Terms and Definitions

Source: https://pixabay.com/photos/anatomy-man-human-body-skin-254129/

function msg1() { document.getElementById(“button1″).value=”anchoring junction”; } – are cell junctions that are attached to one another; attached to structures of the extracellular matrix

function msg11() { document.getElementById(“button11″).value=”apical”; } – refers to the top surface

function msg12() { document.getElementById(“button12″).value=”basal”; } – refers to the bottom surface

function msg13() { document.getElementById(“button13″).value=”blast”; } – word which means to produce, as in osteoblast

function msg14() { document.getElementById(“button14″).value=”bone cell matrix”; } – composed of collagen fibers and calcium phosphate salts

function msg15() { document.getElementById(“button15″).value=”calcium phosphate”; } – is a mineral found in the bone

function msg16() { document.getElementById(“button16″).value=”canaliculi”; } – are passages that allow blood and bone cells to communicate

function msg17() { document.getElementById(“button17″).value=”cardiac muscle tissue”; } – muscle tissue found in the heart which is branched and striated; it has dark line between cells which is called an intercalated disc

function msg18() { document.getElementById(“button18″).value=”cellular layer”; } – layer of periosteum where the osteoblast can be found

function msg19() { document.getElementById(“button19″).value=”central canal”; } – bone canal which the blood vessels and nerves can be found

function msg10() { document.getElementById(“button10″).value=”chondrocytes”; } – also known as the cartilage cells

function msg1a() { document.getElementById(“button1a”).value=”chondroitin sulfate”; } – is a chemical found in cartilage

function msg1b() { document.getElementById(“button1b”).value=”collagen”; } – is the most abundant protein found in the bones, muscles, skin, and tendons

function msg1c() { document.getElementById(“button1c”).value=”collagen fiber”; } – a fiber which gives strength

function msg1d() { document.getElementById(“button1d”).value=”columnar”; } – refers to column-shaped; as in columnar epithelium

function msg1e() { document.getElementById(“button1e”).value=”compact tissue bone”; } – tissue found on the surface of the bone

function msg1f() { document.getElementById(“button1f”).value=”cross section”; } – section which cuts across the short dimension

function msg1g() { document.getElementById(“button1g”).value=”cuboidal”; } – refers to cube-shaped, as in cuboidal epithelium

function msg1h() { document.getElementById(“button1h”).value=”dendrites”; } – part of nerve cell that receives stimulus

function msg1i() { document.getElementById(“button1i”).value=”differentiation”; } – the process by which undifferentiated cell becomes more specific type of cell

function msg1j() { document.getElementById(“button1j”).value=”ectoderm”; } – early development tissue that differentiate into nerve cells, neuroglial cell, brain, spinal cord, nerves, epidermis of skin

function msg1k() { document.getElementById(“button1k”).value=”elastic fiber”; } – a biological fiber that provides elasticity

function msg1l() { document.getElementById(“button1l”).value=”endoderm”; } – early development tissue that differentiate into internal linings of respiratory tract and digestive system

function msg1m() { document.getElementById(“button1m”).value=”epithelial tissue”; } – body tissue with a free surface that acts as a barrier; composed of closely packed cells and has the ability to regenerate

function msg1n() { document.getElementById(“button1n”).value=”fibrous layer”; } – layer of periosteum made up of collagen

function msg1o() { document.getElementById(“button1o”).value=”frontal section”; } – section that splits the frontal and the dorsal region; also called coronal section

function msg1p() { document.getElementById(“button1p”).value=”glial cells”; } – are cells that help and assist the activity of nerve cells

function msg1q() { document.getElementById(“button1q”).value=”Haversian canal”; } – the central canal in bone

function msg1r() { document.getElementById(“button1r”).value=”Haversian system”; } – also called the osteon

function msg1s() { document.getElementById(“button1s”).value=”histamine”; } – a compound which promotes blood flow and capillary permeability

function msg1t() { document.getElementById(“button1t”).value=”homeostasis”; } – regulation of a relatively constant internal environment in response to changes from the external environment

function msg1u() { document.getElementById(“button1u”).value=”internal environment”; } – compose of extracellular fluid (plasma, interstitial fluid); the environment around the cell

function msg1v() { document.getElementById(“button1v”).value=”lacunae”; } – bone cavity where osteocytes can be found

function msg1w() { document.getElementById(“button1w”).value=”lamellae”; } – the matrix of the bone

function msg1x() { document.getElementById(“button1x”).value=”longitudinal section”; } – section which cuts down the longest dimension

function msg1y() { document.getElementById(“button1y”).value=”mast cell”; } – white blood cell that releases histamine and causes inflammation

function msg1z() { document.getElementById(“button1z”).value=”mesoderm”; } – early development tissue that differentiate into kidney, liver, muscles, and bones

function msg111() { document.getElementById(“button111″).value=”microvilli”; } – minute projections from the surface of some cells which increases the surface area and can be found in digestive tracts

function msg112() { document.getElementById(“button112″).value=”midsagittal section”; } – section that splits right and left region equally

function msg113() { document.getElementById(“button113″).value=”mitosis”; } – is the process of cell division

function msg114() { document.getElementById(“button114″).value=”monocytes”; } – while blood cells that give rise to macrophages and dendritic cells

function msg115() { document.getElementById(“button115″).value=”nerve fibers”; } – also called the axon of nerve cells

function msg116() { document.getElementById(“button116″).value=”organ”; } – group tissues that has a specific function such as heart or lungs

function msg117() { document.getElementById(“button117″).value=”organ system”; } – group of organs that work together to perform a specific function such as skeletal system or muscular system

function msg118() { document.getElementById(“button118″).value=”organism”; } – group of organ system working together for common function such as human or an animal

function msg119() { document.getElementById(“button119″).value=”osteoblast”; } – a bone cell responsible for production of bone tissue matrix; involves in bone growth, repair, and remodeling

function msg120() { document.getElementById(“button120″).value=”osteoclast”; } – bone cell responsible for breaking down of bone tissue

function msg121() { document.getElementById(“button121″).value=”osteocyte”; } – bone cell responsible for the maintenance of bone tissue

function msg122() { document.getElementById(“button122″).value=”osteon”; } – unit structure of thick compact bone tissue

function msg123() { document.getElementById(“button123″).value=”osteoprogenitor cell”; } – the bone stem cell which differentiate into osteoblast and osteocyte

function msg124() { document.getElementById(“button124″).value=”parasagittal section”; } – section that splits right and left regions unequally

function msg125() { document.getElementById(“button125″).value=”periosteum”; } – a dense layer of vascular connective tissue surrounding the bones except at the surfaces of the joints

function msg126() { document.getElementById(“button126″).value=”phagocytosis”; } – the process of engulfing materials and bacteria by a cell

function msg127() { document.getElementById(“button127″).value=”pseudostratified”; } – refers to a single layer but looks many, as in pseudostratified epithelium

function msg128() { document.getElementById(“button128″).value=”red bone marrow”; } – bone marrow responsible for the production of red blood cell and white blood cell

function msg129() { document.getElementById(“button129″).value=”sagittal section”; } – section that splits the right and left regions

function msg130() { document.getElementById(“button130″).value=”secretion”; } – the process of releasing substances by a cell into the internal environment or into body cavities or ducts

function msg131() { document.getElementById(“button131″).value=”simple”; } – refers to one layer, as in simple squamous epithelium

function msg132() { document.getElementById(“button132″).value=”skeletal muscle tissue”; } – muscle tissue which is striated and voluntary

function msg1qq() { document.getElementById(“button1qq”).value=”smooth muscle tissue”; } – muscle tissue which is not branched in appearance but has a spindle-shaped structure; also called involuntary muscle tissue

function msg133() { document.getElementById(“button133″).value=”spongy bones”; } – also called cancellous which is located within bones; consist of branching plates called trabeculae

function msg134() { document.getElementById(“button134″).value=”squamous”; } – refers to flat, as in simple squamous epithelium

function msg135() { document.getElementById(“button135″).value=”stereocilia”; } – mechano-sensing organelles of hair cells found in inner ear

function msg136() { document.getElementById(“button136″).value=”stratified”; } – refers to many layers, as in stratified epithelium

function msg137() { document.getElementById(“button137″).value=”tissue”; } – group of cells that perform a specific function

function msg138() { document.getElementById(“button138″).value=”trabeculae”; } – the branching plates found in spongy bones

function msg139() { document.getElementById(“button139″).value=”transitional epithelium”; } – epithelium that can be stretched and unstretched; found in the linings of urinary bladder and ureters

function msg140() { document.getElementById(“button140″).value=”transverse section”; } – section that splits the upper from lower regions; also called cross section

function msg141() { document.getElementById(“button141″).value=”yellow bone marrow”; } – bone marrow made up of fats

function msg142() { document.getElementById(“button142″).value=”zygote”; } – a cell that results from the fusion of sperm cell and ovum

Common Anatomical Terms for Pre-Nursing and Pre-Medicine Students

Here is a list of most common anatomical terms that are most likely to be used by pre-nursing and pre-medicine students. Most students encounter these terms in Human Anatomy and Physiology courses.

function msg1() { document.getElementById(“button1″).value=”cephalic”; } – head
function msg2() { document.getElementById(“button2″).value=”orbital”; } – eye
function msg3() { document.getElementById(“button3″).value=”otic”; } – ear
function msg4() { document.getElementById(“button4″).value=”buccal”; } – cheek
function msg5() { document.getElementById(“button5″).value=”cervical”; } – neck
function msg6() { document.getElementById(“button6″).value=”thoracic”; } – chest
function msg7() { document.getElementById(“button7″).value=”mammary”; } – breast
function msg8() { document.getElementById(“button8″).value=”abdominal”; } – abdomen
function msg9() { document.getElementById(“button9″).value=”umbilical”; } – navel
function msg10() { document.getElementById(“button10″).value=”mental”; } – chin
function msg11() { document.getElementById(“button11″).value=”axillary”; } – armpit
function msg12() { document.getElementById(“button12″).value=”brachial”; } – arm
function msg13() { document.getElementById(“button13″).value=”antecubital”; } – front of elbow
function msg14() { document.getElementById(“button14″).value=”antebrachial”; } – forearm
function msg15() { document.getElementById(“button15″).value=”carpal”; } – wrist
function msg16() { document.getElementById(“button16″).value=”palmar”; } – palm
function msg17() { document.getElementById(“button17″).value=”phalangeal”; } – fingers or toes
function msg18() { document.getElementById(“button18″).value=”pollex”; } – thumb
function msg19() { document.getElementById(“button19″).value=”patellar”; } – knee
function msg20() { document.getElementById(“button20″).value=”crural”; } – leg
function msg21() { document.getElementById(“button21″).value=”tarsal”; } – ankle
function msg22() { document.getElementById(“button22″).value=”hallux”; } – great toe
function msg23() { document.getElementById(“button23″).value=”pedal”; } – foot
function msg24() { document.getElementById(“button24″).value=”femoral”; } – thigh
function msg25() { document.getElementById(“button25″).value=”inguinal”; } – groin
function msg26() { document.getElementById(“button26″).value=”pubis”; } – pubic
function msg27() { document.getElementById(“button27″).value=”pelvic”; } – pelvis
function msg28() { document.getElementById(“button28″).value=”acromial”; } – shoulder
function msg29() { document.getElementById(“button29″).value=”dorsal”; } – back
function msg30() { document.getElementById(“button30″).value=”olecranal”; } – elbow
function msg31() { document.getElementById(“button31″).value=”lumbar”; } – loin
function msg32() { document.getElementById(“button32″).value=”gluteal”; } – buttocks
function msg33() { document.getElementById(“button33″).value=”popliteal”; } – back of knee
function msg34() { document.getElementById(“button34″).value=”sural”; } – calf or back of leg
function msg35() { document.getElementById(“button35″).value=”calcaneal”; } – heel
function msg36() { document.getElementById(“button36″).value=”plantar”; } – sole of foot
function msg37() { document.getElementById(“button37″).value=”cranial”; } – skull
function msg38() { document.getElementById(“button38″).value=”frontal”; } – forehead
function msg39() { document.getElementById(“button39″).value=”nasal”; } – nose
function msg40() { document.getElementById(“button40″).value=”manual”; } – hand