Collegebiology

We found 14 articles

Hormones of the female reproductive system
The female reproductive system can at times feel like a difficult jumble of hormones that all seem to be related, but fluctuate in unpredictable ways. To make sense of the particularities of the female reproductive system, especially for exams like the MCAT, it is important to not only know what hormones are involved, but also to understand what ...
Gametogenesis and spermatogenesis and oogenesis, oh my!
Meiosis is one of those processes that we all learned about in high school biology as a deceptively simple concept. You take the diploid cell, divide it twice, and it becomes four haploid gametes that are each capable of participating in fertilization. Easy, right?
Pituitary gland hormones made simple
What is the pituitary gland? Even though the pituitary gland is about the size of a pea, it plays a very important role in regulating a lot of our body’s endocrine functions. Located in an area known as the sella turcica at the base of the brain and suspended from the hypothalamus by a stalk, the pituitary gland consists of two parts: the ...
What are lymphocytes? A guide to your immune system
The immune system is designed to prevent disease and fight infection and is critical for human survival. It specializes in the ability to attack foreign microorganisms, but what stops your immune system from eating you alive? Given that cells of the immune system can essentially eat microorganisms, you may be wondering what mechanisms are in place ...
How do enzymes work? Catalytic strategies and models of substrate fit
In this post, we are going to do a brief Q and A to review what enzymes do and how they work. This post will be slightly beyond a basic introduction so it is probably most appropriate for a student who already has a sense of what enzymes are.
What is the phospholipid bilayer and what determines its fluidity?
All cells are surrounded by a cell membrane that forms a barrier between the cell and its surroundings. This membrane is often referred to as the phospholipid bilayer. As you can probably tell from the name, a phospholipid bilayer is made up of two layers of lipids. The fluidity of this membrane must be maintained within a certain range for the ...
An introduction to blood types: genotype, phenotype, inheritance, transfusion, and more!
What determines blood type? Contained within their cell membranes, some red blood cells have special glycolipids called A and B glycolipids. People with blood type A have the A glycolipid in their cell membranes, people with blood type B have the B glycolipid in their cell membranes, and people with blood type AB, have both glycolipids in their ...
How do we classify mutations in biology?
In the previous post, we discussed some of the built in mechanisms that help to prevent mutations. Sometimes, however, mutations occur in spite of these systems. There are a few different ways that mutations are typically classified in an intro biology course and there are often overlaps between these categories. Here is a brief review of some of ...
Preventing and repairing DNA mistakes during the cell cycle
If you are currently studying biology, you have probably learned that mistakes in DNA can create very big problems, including cancer. These DNA errors often (but not always) occur during replication. Whenever they occur, it is very important for the cell to have a set of systems in place to both prevent and repair these errors. In this blog post, ...
Tips for interpreting pedigree charts and understanding inheritance patterns!
Different traits are inherited in different ways. Many intro biology classes will expect you to be able to identify different patterns of inheritance and parental genotypes based on either a pedigree or the rates of a given phenotype in the offspring. It is helpful to be familiar with the phenotype ratios, pedigree charts, and the specifics of the ...
Essential tips for learning the anterior pituitary hormones
Learning the anterior pituitary hormones for your biology class or the MCAT can be a little overwhelming. It is easy to get lost in the weeds and struggle to see how it all connects. One thing that helped me when I was learning the anterior pituitary hormones was to visualize the connections between the most important structures. This both helped ...
Breaking down nephron functioning into six easy steps!
The nephron is the kidney’s smallest functional unit. It works to ensure that the urine you excrete leaves your body in the correct volume and concentration. This is a complicated process, but once you master it, it is exciting to understand this important function of the human body!
Tips and mnemonics for memorizing amino acid structures
Learning amino acid structures is a challenging part of biology and biochemistry coursework. Many students feel totally overwhelmed by the task. The best way to master this skill is lots of repetition (here is a link to a Sporcle quiz that may help you with the repetition part) but it can be helpful to have tricks and mnemonics to get you started. ...