Biology Part 2 Flashcards
Organs in the Circulatory System
Heart, arteries (aorta), arterioles, veins (vena cava), venules, capillaries, RBC, WBC, platelets, bone marrow stem cells
heart
- A muscular pump that supplies blood to the body
- Right Atrium: Pumps oxygen poor blood to the right ventricle
- Right Ventricle: Pumps the oxygen poor blood to the lungs where it becomes oxygenated
- Left Atrium: Pumps oxygenated blood to the left ventricle
- Left Ventricle: Pumps oxygenated blood to the rest of the body
- Contains lots of cardiac muscle
Arteries (aorta):
- Anything that leaves the heart → aorta just means the largest artery in the body
- Lined with muscular walls to withstand the force of the blood (thick - high blood pressure)
- Left Pulmonary Artery
- Carries deoxygenated blood to the left lung where gas exchange takes place
- Right Pulmonary Artery
- Carries deoxygenated blood to the right lung where gas exchange takes place
- Arch of the Aorta
- Pumps blood to the upper body
- Descending Aorta
- Pumps blood to the lower body
Arterioles:
Narrow, small blood vessels that branch off the arteries and carry blood to to the tissues and organs
Capillaries:
Smallest blood vessels in the body (one cell thick)
Veins (vena cava):
- Anything that enters the heart
- Thin - lower blood pressure than arteries - have valves
- Pulmonary veins takes oxygenated blood from the lungs to the left atrium to the heart
- Vena cava: large vein that carries blood to the heart (superior and inferior)
Venules:
The smallest veins that receive oxygen poor blood from the capillaries and deliver it back to the heart
Red Blood Cells:
Pick up oxygen in the lungs
White Blood Cells:
Locate dangers when travelling through the bloodstream
Bone Marrow Stem Cells:
Cells that develop into RBC, WBC, and platelets
Platelets:
Prevents and stops bleeding
Order of blood flow
Superior and inferior vena cava → right atrium → right ventricle → pulmonary arteries→ through capillaries around alveoli → pulmonary veins → left atrium → left ventricle → aortic arch → arterioles → capillaries (past every cell in the body) → venules → superior and inferior vena cava
cancer screening tests
Cancer screening tests aim to find cancer before it causes symptoms and when it may be easier to treat successfully. An effective screening test is one that
- finds cancer early
- reduces the chance that someone who is screened regularly will die from the cancer
- has more potential benefits than harms (possible harms of screening tests include bleeding or other physical damage, false-positive or false-negative test results, and overdiagnosis—the diagnosis of cancers that would not have caused problems and did not need treatment)
5 elements of dna
oxygen, carbon, nitrogen, hydrogen, phosphorus
dna extra info
- DNA has a double helix structure (like a twisted ladder)
- Helixes coil up and form a chromosome
- 23 pairs of chromosomes in the body
- The entire thing is called a adenine nucleotide
carcinogens
- Substances that may increase your risk of developing cancer
- They are environmental factors that lead to cancer
- Experts have identified more than 100 carcinogens
- Physical carcinogens: particles of soft or hard material that are not soluble in water
- Ultraviolet rays, electromagnetic radiations, corpuscular radiations
- Chemical carcinogens: substances that seep into cell
- Asbestos, tobacco smoke, aflatoxin
- Biological carcinogens: RNA that overtakes cell
- Bacteria, parasites, infections caused by certain viruses
- Simply having contact with a carcinogen doesn’t mean you’ll develop cancer. While you may not be able to avoid some carcinogens, there are steps you can take to reduce your risk of developing cancer from carcinogen exposure
Normal Cell Vs. Cancerous Cell
- Normal cells divide and multiply in a controlled manner. Cancerous cells multiply uncontrollably (don’t stay in interphase for long enough)
- Normal cells are programmed to die (apoptosis). Cancerous cells ignore those directions.
- Normal cells for solid organs stay put. All cancerous cells are able to move around (metastasis)
- Normal cells don’t grow as fast as cancerous cells.
tumors
- Rapidly growing mass of cells
- Benign (not cancerous) versus malignant
- Benign tumors can get so large they crowd surrounding cells and affect their function, which makes them malignant
- Body has genes to suppress tumor growth, but they can be manipulated by the cancerous cells
mutations
- Random changes in the DNA
1. Base-pair substitution: a nucleotide is replaced by a different nucleotide
2. Insertions: a nucleotide is added to the DNA sequence
3. Deletions: a nucleotide is removed from the DNA sequence
4. Inversions: a DNA segment breaks off a chromosome, flips in orientation, and reattaches to the same chromosome
5. Translocation: movement of DNA segment from one chromosome to another
6. Duplication: a DNA segment is duplicated, resulting in multiple copies of that DNA segment within that chromosome