Category: Study Guides

IMMUNODEFICIENCY NOTES

Immunodeficiency is the failure of the immune system to protect against disease or malignancy. Primary Immunodeficiency is caused by genetic or developmental defects in the immune system. These defects are present at birth but may show up later on in life. Secondary or acquired immunodeficiency is the loss of immune function as a result of exposure to disease agents, environmental factors, immunosuppression, or aging.

SECONDARY (ACQUIRED) IMMUNODEFICIENCIES

Immunodeficiencies associated with infections

Bacterial, viral, protozoan, helminthic and fungal infections may lead to B cell, T cell, PMN and macrophage deficiencies. Most prominent among these is acquired immunodeficiency syndrome (AIDS). Secondary immunodeficiencies are also seen in malignancies.

Immunologic abnormalities in the AIDS

All acquired immunodeficiencies have been outdone by AIDS that is caused by Human Immunodeficiency Virus (HIV)-1. This virus was first discovered in 1981 and the patients exhibited fungal infections with opportunistic organisms such as Pneumocystis carinii and in other cases, with a skin tumor known as Kaposi’s sarcoma. There are two major types of HIV: HIV-1 and 2, the former being the strain frequently found in North America. HIV is spread through sexual intercourse, infected blood and body fluids as well as from mother to
offspring. HIV, which was discovered in 1983, is a retrovirus with RNA that is reverse transcribed to DNA by reverse transciptase (RT) following entry into the cell. The DNA is integrated into the cell genome as a provirus that is replicated along with the cell. HIV-1 does not replicate in most other animals but infects chimpanzees although it does not induce AIDS in them. Severe combined immunodeficient mice (SCID) reconstituted with human lymphocytes can be infected with HIV-1. The HIV-1 virion consists of a viral envelope made
up of the outer lipid bilayer of the host cell in which are embedded glycoproteins composed of the transmembrane gp41 along with the associated gp120. The gp120 binds the CD4 expressed on host cells. Within the viral envelope is the viral core or nucleocapsid consisting of a layer of matrix protein composed of p17 and an inner capsid made up of p24. The viral genome consists of two single stranded RNA molecules associated with two RT molecules as
well as other enzymes including a protease and an integrase.

Replication cycle and targets of therapy

The virus attaches to the CD4 molecule on Th cells, monocytes and dendritic cells through the gp120 of HIV. For HIV infection, a co-receptor is required. The co-receptor is a chemokine receptor such as CXCR4 or CCR5. CCR5, expressed predominantly on macrophages, and CXCR4 on CD4+ T cells serve as coreceptors for HIV infection. After the fusion of HIV envelope and the host membrane, the nucleocapsid enters the cell. The RT synthesizes viral DNA which is transported to the nucleus where it integrates with the cell
DNA in the form of a provirus. The provirus can remain latent till the cell is activated when the provirus also undergoes transcription. Virions, consisting of the transcribed viral RNA and proteins, are produced. These bud out of the host cell membrane from where they acquire the envelope. Thus, therapeutic agents have been developed that target viral entry and fusion, as well as serve as RT, protease and integrates inhibitors. Highly active anti-retroviral therapy
is a cocktail of 3 or more such agents.

Immunological Changes

The virus replicates rapidly and within about two weeks the patient may develop fever. The viral load in the blood increases significantly and peaks in two months, after which there is a sudden decline because of the latent virus found in germinal centers of the lymph nodes. CTL develop very early whereas antibodies can be detected between 3 – 8 weeks. The CTL killing of
of Th cells around 4 – 8 weeks leads to a decrease in CD4+ T cells. When the CD4+ T cell count decreases below 200 per cubic mm, full blown AIDS develops.

Immunotherapy

There are several barriers to development of an effective HIV vaccine.

 Attenuated vaccine may induce the disease
 CD4+ T cells may be destroyed by the vaccine
 Antigenic variation of HIV
 Low immunogenicity of the virus by downregulation of MHC molecules
 Lack of animal models
 Lack of in vitro tests

The following reagents have been considered in developing vaccines:

 Immunization with deletion mutants to reduce pathogenicity
 Vaccination with recombinant proteins
 Gene encoding proteins introduced into virus vectors may be used for
vaccination
 Chemokines that compete for the co-receptors
 IL-2 to boost the Th cells.

Immunodeficiencies associated with aging

These include a progressive decrease in thymic cortex, hypo-cellularity of and reduction in the size of thymus, a decrease in suppressor cell function and hence an increase in auto-reactivity, a decrease in CD4 cells functions. By contrast B cells functions may be somewhat elevated.

Immunodeficiencies associated with malignancies and other diseases

B cell deficiencies have been noted in multiple myeloma, Waldenstrom’s macroglobulinemia, chronic lymphocytic leukemia and well differentiated lymphomas. Hodgkin’s disease and advanced solid tumors are associated with impaired T-cell functions. Most chemotherapeutic agents used for treatment of malignancies are also immunosuppressive.

Other conditions in which secondary immunodeficiencies occur are sickle cell anemia, diabetes mellitus, protein calorie malnutrition, burns, alcoholic cirrhosis, rheumatoid arthritis, renal malfunction, etc.

PRIMARY IMMUNODEFICIENCIES

Primary immunodeficiencies are inherited defects of the immune system (figure 1). These defects may be in the specific or non-specific immune mechanisms. They are classified on the basis of the site of lesion in the developmental or differentiation pathway of the immune system. Individuals with immunodeficiencies are susceptible to a variety of infections and the
type of infection depends on the nature of immunodeficiency (Table 1).

SPECIFIC IMMUNE SYSTEM

There are a variety of immunodeficiencies which result from defects in stem cell differentiation and may involve T-cells, B-cells, and/or immunoglobulins of different classes and subclasses (Table 2).

A defect in the early hematopoiesis which involves stem cells results in reticular dysgenesis that leads to general immune defects and subsequent susceptibility to infections. This condition is often fatal but very rare.

Lymphoid lineage immunodeficiency

If the lymphoid progenitor cells are defective, then both the T and B cell lineages are affected and result in the severe combined immunodeficiency (SCID). Infants suffer from recurrent infections especially by opportunistic micro-organisms (bacterial, viral, mycotic and protozoan infections).

In about 50% of SCID patients, the immunodeficiency is x-linked whereas in the other half the deficiency is autosomal. Both are characterized by an absence of T cell and B cell immunity and absence (or very low numbers) of circulating T and B lymphocytes. Thymic shadows are absent on X-rays.

The x-linked severe SCID is due to a defect in the gamma-chain of IL-2 also shared by IL-4,-7, -11 and 15, all of which are involved in lymphocyte proliferation and/or differentiation. The autosomal SCIDs arise primarily from defects in adenosine deaminase (ADA) or purine nucleoside phosphorylase (PNP) genes which results is accumulation of dATP or dGTP, respectively, and cause toxicity to lymphoid stem cells. Other genetic defects leading to
SCID include those for RAG1, RAG2 and IL-7-alpha. If suspected of SCID, the patient must not receive live vaccine, as it will result in progressing disease.

Diagnosis is based on enumeration of T and B cells and immunoglobulin measurement. Severe combined immunodeficiency can be treated with a bone marrow transplant (see MHC and transplantation). Recently, autosomal SCID patients with ADA deficiency have been treated with a retroviral vector transfected with the gene with some success.

SCID includes several disorders


Patients having both T and B cell deficiency lack recombinase activating genes (RAG1 and 2) that are responsible for the T cell receptor and Ig gene rearrangements. These patients are athymic and are diagnosed by examining the T cell receptor (TCR) gene rearrangement. Defects in B cells are not observed in early infant life because of passive antibodies obtained from the mother. NK cells are normal.

In some SCID patients, T cells may be present but functionally defective because of deficiency in signaling mediated by the CD3 chain that is associated with the TCR.

Interleukin-2 receptor common gamma chain (IL-2Rγc) may be lacking in patients there by preventing signaling by IL-2, 4, 7, 9 and 15. These patients are T and NK cell deficient.

Adenosine deaminase (ADA) is responsible for converting adenosine to inosine. ADA deficiency leads to accumulation of adenosine which interferes with DNA synthesis. The patients have defects in T, B and NK cells.

Disorders of T cells

DiGeorge’s Syndrome (Deletion 22 Syndrome)

This the most clearly defined T-cell immunodeficiency and is also known as congenital thymic aplasia/hypoplasia, or immunodeficiency with hypoparathyroidism. The syndrome is associated with hypoparathyroidism, congenital heart disease, low set notched ears and fish shaped mouth. These defects results from abnormal development of the fetus during the 6th to 10th week of gestation when parathyroid, thymus, lips, ears and aortic arch are being formed. No genetic predisposition is clear and not all DiGeorge syndrome babies have thymic aplasia. A thymic graft taken from an early fetus (13 – 14 weeks of gestation) can be used for treatment. Older grafts may result in GVH reaction. In severely immunodeficient DiGeorge patients, live vaccines may cause progressive infections.

DiGeorge syndrome is autosomal dominant (figure 2) and is caused by a deletion in chromosome 22 (figure 3). The deletions are of variable size but size does not correlate with severity of disease. In about 6% of cases, the chromosome 22 micro-deletion is inherited but most cases result from de novo deletion which may be caused by environmental factors.

T cell deficiencies with variable degrees of B cell deficiency

Ataxia-telangiectasia

Ataxia-telangiectasia is a deficiency of T cells associated with a lack of coordination of movement (ataxis) and dilation of small blood vessels of the facial area (telangiectasis). T- cells and their functions are reduced to various degrees. B cell numbers and IgM concentrations are normal to low. IgG is often reduced and IgA is considerably reduced (in 70% of the cases). There is a high incidence of malignancy, particularly leukemias, in these patients. The defects arise from a breakage in chromosome 14 at the site of TCR and Ig heavy
chain genes.

Wiskott-Aldrich syndrome

This syndrome is associated with normal T cell numbers with reduced functions, which get progressively worse. IgM concentrations are reduced but IgG levels are normal. Both IgA and IgE levels are elevated. Boys with this syndrome develop severe eczema, petechia (due to platelet defect and thrombocytopenia). They respond poorly to polysaccharide antigens and
are prone to pyogenic infection. Wiskott-Aldrich syndrome is an X-linked disorder (figure 4) due to defect in a cytoskeletal glycoprotein, CD43.

MHC deficiency (Bare leukocyte syndrome)

A number of cases of immunodeficiency have been described in which there is a defect in the MHC class II transactivator (CIITA) protein gene, which results in a lack of class-II MHC molecule on their APC. Since the positive selection of CD4 cells in the thymus depends on the presence of these MHC molecules, these patients have fewer CD4 cells and are infection prone. There are also individuals who have a defect in their transport associated protein (TAP) gene and hence do not express the class-I MHC molecules and consequently are deficient in CD8+ T cells.

Disorders of B lymphocytes

There are a number of diseases in which T cell numbers and functions are normal: B cell numbers may be low or normal but immunoglobulin levels are low. These are briefly summarized below.

X-linked infantile hypogammaglobulinemia

X-linked hypogammaglobulinemia, also referred to as Bruton’s hypoglobulinemia or agammaglobulinemia, is the most severe hypogammaglobulinemia in which B cell numbers and all immunoglobulin levels are very low. The patients have failure of B-cell maturation associated with a defective B cell tyrosine kinase (btk) gene. Diagnosis is based on
enumeration of B cells and immunoglobulin measurement.

Transient hypogammaglobulinemia

Children, at birth, have IgG levels comparable to that of the mother. Because the half life of IgG is about 30 days, its level gradually declines, but by three months of age normal infants begin to synthesize their own IgG. In some infants, however, IgG synthesis may not begin until they are 2 to 3 years old. This delay has been attributed to poor T cell help. This results in a transient deficiency of IgG which can be treated with gamma-globulin.

Common variable hypogammaglobulinemia (Late onset hypogammaglobulinemia)

These individuals have acquired deficiencies of IgG and IgA in the 2nd or 3rd decade of their life and are susceptible to a variety of pyogenic bacteria and intestinal protozoa. They should be treated with specially prepared gamma-globulin for intravenous use.

IgA deficiency

IgA deficiency is the commonest of all immunodeficiencies (1/700 of all Caucasians). About 20% of individuals with IgA deficiency also have low IgG. IgA-deficient patients are very susceptible to gastrointestinal, eye and nasopharyngeal infections. Patients with IgA deficiency have a high incidence of autoimmune diseases (particularly immune complex type) and lymphoid malignancies. Anti-IgA antibodies (IgG) are detected in 30 to 40 percent
of patients who should not be treated with γ-globulins. Laboratory diagnosis is based on IgA measurement.

Selective IgG deficiency

Deficiencies of different IgG subclasses have been found. These patients are susceptible to pyogenic infections.

Hyper-IgM immunodeficiency

Individuals with this type of immunodeficiency have low IgA and IgG concentrations with abnormally high levels of IgM. These patients cannot make a switch from IgM to other classes which is attributed to a defect in CD40L on their CD4 cells. They are very susceptible to pyogenic infection and should be treated with intravenous gamma-globulins.

NON-SPECIFIC IMMUNE SYSTEM

Primary immunodeficiencies of the non-specific immune system include defects in phagocytic and NK cells and the complement system.

Defects of the phagocytic system

Defects of phagocytic cells (numbers and/or functions) can lead to increased susceptibility to a variety of infections.

Cyclicneutropenia

This is marked by low numbers of circulating neutrophil approximately every three weeks. The neutropenia lasts about a week during which the patients are susceptible to infection. The defect appears to be due to poor regulation of neutrophil production.

Chronic granulomatous disease(CGD)

CGD is characterized by marked lymphadenopathy, hepato- splenomegaly and chronic draining lymph nodes. Leukocytes have poor intracellular killing (figure 5) and low respiratory burst. In majority of these patients, the deficiency is due to a defect in NADPH oxidase (cytochrome b558 : gp91phox, or rarely gp22phox) or other cofactor proteins (gp47phox, gp67phox) that participate in phagocytic respiratory burst. These patients can be diagnosed on the basis or poor Nitroblue tetrazolium (NBT) reduction which is a measure of respiratory burst. Interferon-gamma therapy has been successful.

Leukocyte Adhesion Deficiency

In this disease, leukocytes lack the complement receptor CR3 due to a defect in
CD11 or CD18 peptides and consequently they cannot respond to C3b opsonin.
Alternatively there may a defect in integrin molecules, LFA-1 or mac-1 arising
from defective CD11a or CD11b peptides, respectively. These molecules are involved in diapedesis and hence defective neutrophils cannot respond effectively to chemotactic signals.

Chediak-Higashi syndrome

Chediak-Higashi syndrome is marked by reduced (slower rate) intracellular killing and chemotactic movement accompanied by inability of phagosome and lysosome fusion and proteinase deficiency. Giant lysosomes (intracellular granules) are often seen (figure 6). The respiratory burst is normal. Accompanying NK cell defects and platelet and neurological disorders are noted.

DISORDERS OF COMPLEMENT SYSTEM

Complement abnormalities also lead to increased susceptibility to infections. There are genetic deficiencies of various components of complement system, which lead to increased infections. The most serious among these is the C3 deficiency which may arise from low C3 synthesis or deficiency in factor I or factor H.

Advice for Biology Speciality Students in 2022

 When you study biology, you have more understanding of the diversity of life and how biological systems work. You learn the interdependence of life forms and the influence of genetics. The world is facing many challenges today, and as a biologist, you would be involved in finding solutions. You could have an interesting and lucrative career as a biologist in many different fields, including medicine, teaching or research. 

Specializing in biology can be a great choice for you in 2022. As biology is such a huge field of study, you can choose from many different sub-disciplines. Molecular biology, human biology, environmental biology and plant biology are just a few of the sub-disciplines you could study. 

Understand the career opportunities

Writing a literature review of the highest quality is important in many scientific fields. It’s a time-consuming process that can make coping with other important college tasks difficult. If you’re a biology student who wants help with writing essays, research papers or literature reviews, you can use an essay writing service. Professional literature review writers know how to meet the requirements of the most exacting professors. You will get quality work that’s done by experts that can be called gold-standard. 

There are many different types of jobs for which the study of biology offers a good foundation. If you know which type of career you would like to pursue, you will know which courses you need to concentrate on and which electives to choose. 

Microbiologists study microorganisms such as parasites, viruses, and bacteria. They try to understand their effects on human health, the environment, climate and agriculture. This type of work is crucial in the pharmaceutical and medical fields. The recent pandemic showed just how crucial the job of a microbiologist could be. 

Research scientists conduct experiments of all kinds and often work in laboratories or hospitals. Their studies may contribute to the development of new products or applications and much more. 

Forensic scientists play a role in criminal investigations and analyze evidence for biological clues. They study DNA and organic matter. 

Other jobs you may be interested in are those of a biological technician or environmental scientist. Finding out how to reduce carbon emissions without too many side effects could be part of your work as an environmental scientist. In the field of agriculture, you could help to design the future of crops and food supplies. In the field of medicine, you could. work on the use of antibiotics without creating resistant bacteria. You could also choose to
become a biology teacher or professor and pass on your knowledge. 

Focus on the skills you need to develop

In addition to specific biology subject knowledge, you will learn many other skills while studying biology. Research and data analysis will be an essential part of what you do. You have to apply scientific principles to problems and communicate your findings in a relatable way. Report writing and presentation skills are important. You have to learn how to work independently and collaborate in groups. Time management skills are necessary if
you want to meet deadlines. These are skills you can apply in many different careers. 

Think about the environment in which you want to work

The environment in which you want to work also determines what field of biology you choose to specialize in. You will need to learn how to use technical equipment and specialist techniques in that specific environment. Research organizations often publish reports where they list certain future skills they will require due to changes in the industry. You could focus on getting an education for a brighter future by choosing skills that will be in demand. Experts in skills that are in demand are often very well paid. 

Get an internship or volunteer

You will need to try and get work experience in the relevant field of biology. This will help you to apply your knowledge and develop your practical skills. It will also help you to start forming a network of contacts. 

You can apply for an internship at various institutions to gain valuable work experience. Voluntary work can also be useful. Conservation facilities, schools, research laboratories, science museums, zoos, veterinary practices and other institutions may have opportunities for you as an intern or volunteer. 

Conclusion

Many of the issues the world is facing today are connected to biology, and you could do a
great deal of good in the world as a biology specialist. There are many career options in a
great variety of fields. The sooner you understand what field you would like to work in and
the type of job you want to do, the easier it is to choose the right study path. Becoming an
intern or volunteering can provide you with useful insights if you aren’t sure which area you
want to move into as a biologist.

Preparing to Study Biology

Students entering college find themselves researching different majors: here is some general info on what you may experience getting a degree in Biology.

Many choices confront you as you move into, through, and ultimately beyond high school. When you reach this last phase, you may be torn between a number of your interests as you consider what school to attend and what majors to consider when you get there. Like you, many including myself struggled with this question and made their choices for better or worse.

Hopefully, your choice brings you closer to what you want to spend the rest of your life doing (which you probably do not even know yet), but whatever you choose, you have arrived at this article due to at least some minor interest in the science of biology. Besides it, take into account that most courses require to write a lot. Moreover, being an active essay writer, a student is more likely to succeed in his/her study. Most students comprehend and memorize material better while making notes. 

That established, let me try to tell you a little bit about this wonderful topic which has been my own chosen area of study. I’ll try to cover some areas of interest, the potential for employment, and what to expect from your classes.

General

Biology is the science of life. According to one of the most popular college-level textbooks on the subject by Campbell and Reese: “biology is a central science, and attractive to humans because of our basic curiosity about the world around us”.

Biology is the study of all living things and their interactions with each other and their environments. Biology in general is broken up into several other categories, each a completely defined science in itself. Ecology tends to deal mainly with non-human species interactions, while environmental science tends to deal with the impacts of humans on nature.

Anatomy is the study of the human body or the body of one species, while comparative zoology is the study of the similarities and differences between species. As you can see, biology encompasses and overlaps many other sciences.

The Information Explosion

Students studying anything in high school or college currently are in the midst of what is being called an “information explosion.” The information explosion is a widely used term used to refer to the fact that the human race generates new information at a nearly incomprehensible speed. For example, according to the EMC organization, which studies information and information technology, if you wanted to store all of the current information in the world on electronic media like computer memory, you would be short of enough space by about 35%.

This makes specialization within one’s field a necessity for progress. And many biologists have chosen one special area of interest, such as endocrinology, microbiology, immunology, botany, ichthyology, and genetics; to name only a fraction. This practice of specialization is likely to become more pronounced as time moves forward. As such when you get to the more advanced levels of biology you are likely to develop a favorite area of study, and professors will quickly encourage you to try and become an expert in this topic.

Some Areas You Might Get a Job

Biology in all forms is a very engaging and rewarding science to be a part of. Some of the highest paying jobs find their roots in biology, and so do many of the most perplexing scientific questions of all time. Pharmaceuticals, biochemistry, and medicine are among the most recognized in both of these areas, due to the high amount of interest in our health and wellbeing.

Environmentalism is a popular movement in our society and awareness of the human impact on the planet seems to be ever-growing. Academics and government agencies alike are working on environmental issues such as pollution, overpopulation, and irresponsible agricultural practices. Large corporations are discovering that waste and pollution are huge problems for them. Corporate green advocates, environmental public relations, and efficiency experts are all working to rectify the image of the company as the villain by default. Quite simply it is profitable to be green nowadays, and someone with an understanding of green work practices, an interest in the wellbeing of the planet, and a good sense of public image is valuable to a company.

Academic and research biology is a growing field as well. There are barely enough students to accommodate the staggering number of subjects, and new ones seem to be being created almost every month. All of the topics I have previously mentioned can represent entire degrees in and of themselves, each requiring a great number of courses to master. As for the best essay writing service reddit, academic research leads to important new directions for science including the decoding of the human genome and the now almost commonplace practice of genomics: sequencing and studying the genetic codes of humans and other organisms.

Skills You’ll Need for College

Students of biology will experience all facets of a course in a major science. Writing ability, patience with material and vocabulary, and a keen memory and attention to detail are all essential. An understanding of all other major sciences is likely to be required through general education courses by your school, or as a prerequisite for admission into the program. Most important to the science of biology, arguably, would be a good grasp of mathematics, and an excellent understanding of chemistry. My degree required four semesters of chemistry as a minimum, and many of the upper-level biology classes introduce their chemistry concepts. Expect to deal with reaction equations, practices in working safely with chemicals, an understanding of stoichiometry, and the major molecule types important to live. Math students may find an excellent use for their abilities in both ecology and genetics, which analyze populations a great deal. Any biology student should be prepared for periodic crash courses in other topics, to deal with the complexity of life on Earth.

Conclusion

In short, knowledge of biology is currently on the rise in popularity and demand. Students of biology are a valuable commodity and a proven ability to understand the concepts represented within the science is an indispensable skill, both in monetary and scholarly measurement. If your interests fall within saving the planet, making money, solving the mysteries of life, or becoming famous (for modern celebrity biologists search: Craig Venter, Joe Davis, and Tyrone Hayes to name just a few of my personal favorites), then hopefully you can be persuaded into the study of biology, to use your talents for the benefit of all life in our universe.

Oh, and feel free to quote that last line when employers ask you why you want to work for them.

Mastering Biology Terminology In Introductory Courses

Ideas for increasing retention of vocabulary presented in introductory college-level biology courses.

As a teacher, and previously as a student, I have found one of the more frustrating courses to get through is a large survey course like Intro to Biology. The amount of material covered is often daunting, and no topic is covered in enough detail to allow you to get used to the terminology. One of the largest problems is that many students want to succeed but have no idea how to approach the course. It is highly important for students who constantly need help with writing papers for academic purposes throughout the whole course. One of the first things I tell students is that biology courses should be considered and prepared for the same way you would use for a foreign language course.

How to Remember Biology Terminology

Consider the following tips for learning and remembering the many terms that are associated with the field of biology.

Write the words. Write them in your notes. Re-write your notes. Write them on note cards. Write them with definitions that you put into your own words. Simply transcribing word-for-word from the glossary in the back of your textbook is not going to reinforce the actual meaning of the word.

Speak the words. Say them out loud in class (If you have a professor that does not give opportunities for you to speak in class, you may want to suggest they do!). Say them to your study partner when you are reviewing the material. Say them to the wall in your room when no one else is there. Just say them.

Read the words. Biology textbooks have a lot of words in them. You need to find the parts that describe the specific term you are trying to understand and read that section. Highlighting an entire chapter in yellow is not going to help you remember any of the terms, but sifting through the text to find what you are looking for will.

Hear the words. First, you need to listen in class and try to hear what the professor is saying. Second, you might benefit from recording lectures and listening to them again at another time. Some MP3 players have a record feature that will allow you to do this.

Draw the words. Draw the structure, concept, or pathway that is being discussed, and be sure to include clear labeling. Many students are visual learners, and creating a picture of that term on a piece of paper may help with retention. If you feel you cannot draw, consider one of the biology coloring books widely available, or make a copy of figures out of your text and white out the labels so you can re-fill them.

Break down the words. Most biology terms are based on Latin or Greek root words. By breaking down words you can learn the parts of many terms at once. For example, “city” means “cell,” the term “leuko” means “white,” and hence the term “leukocyte” means “white cell”; a white blood cell to be specific. “Cyte” is also included in the names of many other cell types, including “osteocyte,” “erythrocyte” and “lymphocyte.”

Compare the words. Many of the words used in biology sound very similar, but mean very different things. Find the words that look or sound the same and find ways to remember why they are different. For example, glycogen and glucagon differ by only a few letters, but one is a storage molecule and the other is a hormone. The terms might even be discussed in the same chapter or lecture, as they are both related to regulating blood sugar levels, making them even more tricky when it is time to decide between the two on an exam. You could remember that glucagon releases glucose into the bloodstream, and has an “on” together like the word hormone.

Test the words. The best way to learn is through frequent testing of the material. Now, you do not want to wait until your final exam to try this idea. Take advantage of the multiple choice questions in your textbook, or use the website provided by the text to try out some quizzes. If the course you are taking does not provide any of these tools, create your own! Students must use critical thinking when processing the research on their own or asking someone to write my essay for me while considering biological concepts.  This is a very productive way to use your time with a study partner or group. Better yet, each of you prepares a test beforehand and brings it to your session. You can have fun deciding which of you would be the most challenging professor among you!

Succeeding in Your Biology Course

All of these methods may not work for everyone. Different people learn in different ways. Try a few, and if they don’t work, try a few more. One major tip for success is to practice these methods frequently during the course. An all-night cram session is not going to work for this kind of material. Many short review sessions will be much more productive.