Bio: L1-circulatory system Flashcards
Cell theory - three points
- the cell is the basic unit of structure in life
- all living things are made up of one/more cells
- all cells come from pre-existing cells
3 reasons for cell division
Reproduction, growth, repair
Phases of interphase (names and descriptions), talk ab G2 checkpoint
G0 - resting phase: cell is not dividing or preparing to divide (preforms its function)
G1 - Cells grow: get bigger in size, make proteins and organelles, synthesize proteins and RNA (centromere and components of centrosomes are made)
S - synthesis and replication of DNA (DNA is duplicated for there to be enough for both daughter cells)
G2 - cell continues to grow, make proteins and organelles, reorganizes to prep for mitosis.
G2 checkpoint: ensures that DNA is not damaged
4 phases of mitosis
Prophase, metaphase, anaphase, telophase (PMAT)
Duration of interphase on average
24 hours
Duration of mitosis on average
1 hour
What happens during prophase (4)
- Spindle fiber begins to form
- The nucleolus (the organelle that make ribosomes) disappears
- nuclear membrane disintegrates, allowing chromosomes to move freely
- centrosomes move to opposite ends of the cell
What happens during metaphase? (1)
- spindle fibers that came from centrosomes (each containing two centrioles) move chromosomes to the metaphase plate (equator of the cell)
What happens during anaphase? (1)
Each pair of chromosomes is separated into two identical chromosomes by the spindle fiber
What happens during telophase? (3)
- nuclear membrane forms around each set of chromosomes to separate nuclear DNA from the cytoplasm
- chromosomes begin to uncoil
- cell begins to pinch inwards
What happens during cytokinesis? (2)
- This is where the parent cell actually splits into two identical daughter cells.
- When this happens, the cleft formed by the cell membrane pinching in is called the cleavage furrow.
name 12 organelles of a eukaryotic plant cell, + which ones are present in animal cells and which are not
1.Chloroplast (plant only)
2.Endoplasmic reticulum
3.Cell wall (plant only)
4.Nucleus
5.Cell membrane
6.Nuclear membrane
7.Vacuole
8.Mitochondria
9.Cytoplasm
10.Golgi body
11.Ribosomes
12. lysosomes
Functions of each of the following + differences between plant and animal cells:
1.Chloroplast (plant only)
2.Endoplasmic reticulum
3.Cell wall (plant only)
4.Nucleus
5.Cell membrane
6.Nuclear membrane
7.Vacuole
8.Mitochondria
9.Cytoplasm
10.Golgi body
11.Ribosomes
12. lysosomes
Cytoplasm
All organelles are suspended inside of it
Mostly made up of water, also contains salts and organic molecules
Allows organelles to move around
Is the site of many chemical reactions
Cell membrane
Supports the cell, allows substances such as oxygen and water molecules to enter while keeping others such as proteins out
Also surrounds most organelles in a eukaryotic cell
Nucleus
Contains chromosomes, which contain DNA (genetic information)
When a cell divides, DNA is duplicated
Mitochondria
Powerhouse of the cell
Stores energy in the form of glucose
Contains enzymes that convert energy into an easier to use form (cellular respiration)
Cellular Respiration:
Glucose+oxygen → water+CO2+usable energy
In cells where more cellular respiration occurs (ex. Muscle cells), more mitochondria are necessary
Endoplasmic reticulum
3D network of branching tubes and pockets
Extends throughout the cytoplasm
Transport materials throughout the cell
Golgi bodies
Collect and process materials to be removed from the cell
Make and secrete mucus
Vacuole
Single layer of membrane enclosing fluid in a sac
In animal cells, function varies depending on the type of cell (could store waste or regulate cell pressure)
In plant cells, vacuoles keep leaves firm and strong when they are full of water
Cell wall
Outside of cell membrane
Rigid, made out of cellulose
Provides support for cells
Fun fact: cellulose lasts after the cell has died. Paper in books is mostly made up of cellulose from dead cells.
Chloroplast
Absorb light energy, site of photosynthesis
Photosynthesis:
Carbon dioxide + water + energy (sun) → glucose + oxygen
Contain chlorophyll, which gives plants their green colour
Ribosomes
Site of protein synthesis (proteins are made)
Lysosome
Digestive system of the cell: break down compounds from outside, get rid of waste from inside
diffusion
- when a substance is present in different concentrations on opposite sides of the cell membrane, the particles will diffuse
- diffusion: movement of particles from an area of high concentration to an area of low concentraion
explain cancer
Some cells divide often and either are in G0 for a short amount of time or skip G0. Other cells do not divide very often and are in the G0 phase for many years.
When the cell receives the signal to divide, it moves into the G1 phase of the cell cycle.
Cancer cells usually can’t enter G0 and therefore begin to divide uncontrollably
contain an error in the DNA that is replicated to the other cancerous cells
do not perform a specialized function like other cells in our body
malignant vs benign tumour
malignant tumours tend to spread throughout the body (causing more harm) while benign tumours stay in one spot and do not spread)
metastasis
the development of secondary malignant growths at a distance from a primary site of cancer.
difference in appearance between malignant and benign tumours
benign tumours - distinct, smooth, regular borders
malignant - irregular borders, grows much faster
cancer prevention (4)
- healthy diet (avoid foods high in preservatives, chemicals)
- exercise
- avoid toxins like alcohol, tobacco smoke
- avoid other carcinogens such as sun, radiation
cancer diagnosis (4 methods, explain 1)
biopsy - (sample of abnormal tissue is removed and tested)
other methods: ultrasound, x-ray, MRI
cancer treatment (3 methods, explain all)
surgery - physically removing tumour (preferred when tumour is localized)
chemotherapy - drugs that stop cells from rapidly dividing, often first stage of treatment (shrinks tumour)
radiation - radiation damages DNA of cancer cells so that they can no longer divide
visually, how are cancer cells different from normal cells? (4 points)
- normal have larger cytoplasm
- cancerous have multiple nuclei instead of one nucleus
- cancer cells have multiple larger nucleoli instead of one smaller nucleolus
4, cancer cells have courser chromatin than normal cells
what is the nucleolus?
site where ribosomes are synthesized.
How is cancer triggered from the use of cigarette smoke? (4 points)
- Smoke irritates respiratory tract, mucus is produced to resolve this
- Smoke enters respiratory tract and paralyzes cilia, stopping them from keeping anything out
- Carcinogens, such as tar, enter the respiratory tract with no cilia to stop them
- They get caught in the mucus already present and remain in the body, causing cancer
define cellular differenciation
the process by which a cell becomes specialized to preform a specific task
stem cell
an undifferenciated cell taht can divide to form specialized cells based on which gene tissues are being expressed
three categories/levels of stem cells (+ short description - of each)
Totipotent - stem cells that can become any cell in an embryo or adult body
Pluripotent - stem cells that can become any cell in the adult body
Multipotent - stem cells able to become any kind of cell withing one particular lineage
Three kinds of multipotent stem cells, and what they become
hematopoetic - blood cells
neural - nervous system cells
mesenchymal - connective tissues, bones, and cartilage
Two types of pluripotent stem cells (one controversial, one not)
embryonic - must be taken from viable embryos, can be used to regrow various organs
induced pluripotent - taking multipotent adult stem cells and making them pluripotent
Four sections of the heart and locations
Right and left atriums (on top), and right and left ventricles (on the bottom)
Starting at the right atrium, in what order does blood flow through the body?
Right atrium, right ventricle, lungs, left atrium, left ventricle, rest of body
Arteries vs capillaries vs veins
Arteries - away from the heart
Capillaries - delivers blood to the muscles and organs
Veins - back to the heart
Three types of blood cells + function
Red blood cells - carry oxygen
White blood cells - fight disease
Platelets - help stop bleeding
“doors” that control the blood flow through the heart
heart valves
Superior vena cava
vein that leads deoxygenated blood back into the right atrium
inferior vena cava
vein that leads deoxygenated blood back into the right ventricle
valve connecting right atrium and right ventricle
tricuspid valve
Where does blood go after the right ventricle? (3 steps)
The lungs. First it is pushed up into the pulmonary valve, and then into the pulmonary trunk. The pulmonary trunk branches into the right and left pulmonary arteries.
How does blood get from the lungs to the left atrium? (1, easier than you think)
left and right pulmonary veins
After blood goes to lungs, it ends up in left atrium. Where now? (4 steps)
It must get to all other parts of the body. It will go through the mitral valve into the left ventricle. It is then pumped up through the aortic valve into the aorta (largest artery in the body)
