Genetics
What are the first autosomal recessive (requiring two copies of the gene to be inherited) and autosomal dominant (requiring one copy of the gene) disorders?
Alkaptonuria (a recessive metabolic disorder impacting the breakdown of phenylalanine and tyrosine, causing urine that turns black when exposed to air, and eventually arthritis, heart valve damage, and urinary stones, discovered in the early 1900s) and Huntington's disease (a terminal neurodegenerative disease discovered to be dominant in 1872, and mapped onto chromosome 4 in 1983).
How many organ systems exist in the human body?
11 or 12 (it depends on how they are categorized)
What are the four types of macromolecules?
Carbohydrates, lipids, proteins, and nucleic acids
What are the only organelles other than the nucleus that have their own DNA?
Chloroplasts (in plant cells) and mitochondria (in both plant and animal cells)
Do animal cells have vacuoles?
Yes, but they are much smaller than in a plant cell.
Why are people with recessive disorders often the first people in the family to be diagnosed with them?
Recessive disorders require two copies of a mutated gene in order for the disorder to happen - these two copies are often passed down by parents who only have one copy each, and hence typically have no symptoms.
How long is the small intestine?
Around 20 to 22 feet long (around 6 meters)
Why do oil and water not mix?
While water is polar, oil is a lipid, which are typically nonpolar, and therefore hydrophobic - i.e. they do not dissolve in water.
From what parent is mitochondrial DNA passed down through to kids?
The mother
Why do plant cells often look boxy compared to animal cells?
Because of the presence the cell wall, which provides structural support to the plant cell, which is rigid, while animal cells have only a flexible cell membrane.
What is the most common autosomal dominant disorder, affecting 1 in 250 people?
Familial hypercholesterolemia, which causes an overproduction of LDL cholesterol since birth - despite how common it is, it's tragically underdiagnosed, with most people with it not knowing they have it until it causes complications like heart attacks or strokes.
What are the four types of tissues in the body?
Epithelial tissue, connective tissue, muscle tissue, and nervous tissue
What is the difference between catabolism and anabolism?
Catabolism breaks down molecular structures to release ATP, while anabolism uses ATP to build those structures like muscle
How many distinct genes are encoded in mitochondrial DNA?
37
Pompe disease involves a specific enzyme in an organelle rarely found in plant cells being missing, making this organelle unable to break down glycogen, leading to glycogen building up in muscle cells, causing muscles to weaken over time and requiring enzyme replacement therapy to slow down the progression. What is this organelle?
The lysosome
Since men who have an X-linked disorder like hemophilia, having typically only one X chromosome and one Y, can be neither heterozygous (having only one mutated copy and one unaffected copy) nor homozygous (having two mutated copies) for the condition, what are they considered?
Hemizygous for the condition
The peripheral nervous system is divided into two main subtypes - what are they?
How does an enzyme like lactase function?
It acts as a catalyst that speeds up a chemical reaction - it the case of lactose, it helps break down the lactose disaccharide into glucose and galactose in order for it to be digested.
This is a group of genetic disorders where the mitochondria fail to produce enough ATP needed for the body to function, affecting high-metabolism organs like the brain and muscle but often affecting the entire body.
Mitochondrial disease
What is the difference between mitosis and meiosis?
Mitosis involves somatic (not sperm or egg) cells that result in two identical copies per division, while meiosis involves gametes that end up resulting in four genetically different copies.
Mikaeel has Marfan syndrome, a connective tissue disorder affecting mainly the skeleton, eyes, and the heart - it's an autosomal dominant disorder, usually inherited from a parent who has it, yet as far as he and his family knows, there is no family history of Marfan. Why can this happen?
It might have been due to a new (de novo) mutation that happened inside the womb as opposed to passing it down.
What is one of the only cells that do not have mitochondria?
Red blood cells
How many mitochondrial complexes are there in cellular respiration?
Five - Complex I, Complex II, Complex III, Complex IV, and Complex V
1 in how many people have a mitochondrial disease?
1 in 4,000 to 5,000
What does the nucleolus do?
It produces ribosomes