Bio quiz #1 Flashcards
Cell theory
A theory all living cells are made of one or more cell
cells are the smallest and simplest living units that can carry out all life processes
all cells come from the division of a previously existing cell
Prokaryotes
A cell that does not contain a nucleus or other membrane bound organelles.
Eukaryotes
A cell that contains a nucleus and other organelles each surrounded by a thin membrane.
Eukaryotic cells have a structured nucleus, nuclear envelope, brain, organelles like mitochondria, chloroplast, or endoplasmic reticulum, and functions to make the cell self-sufficient.
Cytoplasm
all the material between a cell membrane and the nucleus
Cell membrane
A cell membrane is a thin, flexible barrier that surrounds every cell, separating the cell’s interior from its external environment and regulating what substances can enter and exit the cell
The unique feature of this system is the presence of various proteins on its surface, which serve various functions such as receptors, enzymes, surface antibodies, and transporters.
Nucleus
The nucleus, the largest organelle in a cell, directs all activity, growth, and reproduction, resembling a company manager. It contains DNA (chromosomes) and controls cell growth and reproduction.
Nucleolus
makes ribosomes/ protein synthesizers
Mitochondria
Also known as the powerhouse of the cell, it has functions like digestive systems, consuming nutrients, breaking them down, and producing energy through cellular respiration, a process similar to a digestive system.
Endoplasmic Reticulum
The ER synthesizes and transports proteins and carbohydrates to the Golgi apparatus, plasma membrane, and lysosomes, with two types: rough and smooth.
Ribosomes
Ribosomes are cell-specific protein builders or synthesizers, connecting amino acids at a time to form long chains. They can be found in the cytoplasm or on the endoplasmic reticulum.
Golgi Apparatus
Golgi bodies are responsible for collecting, packaging, and processing materials to be removed from cells, with many found in cells with high mucus content like the intestine or lungs.
Vacuoles
Vacuoles, found in plant and animal cells, are large vesicles used for storing nutrients, maintaining fluid pressure, and storing waste products, with plant cells having larger vacuoles.
Lysosomes
Lysosomes function as garbage disposals, containing chemicals that digest waste and other harmful organisms. They work swiftly when a cell dies, preventing living organisms from becoming filled with dead cells.
Cell Walls
*ONLY PLANT CELLS HAVE CELL WALLS
The plant cell wall, a rigid structure provides a defined shape to plant cells. Its strength surpasses that of most cells, making it the primary reason for the difference between plant and animal cell functions.
Chloroplast
*IN PLANT CELLS ONLY
Chloroplasts, which contain chlorophyll, give plants their green color and enable them to absorb light energy through photosynthesis.
Centrioles
IN ANIMAL CELLS ONLY
involved in cell division
3 stages of the cell cycle
1) Interphase – cells grow and prepare to divide
2) Mitosis –division of the nucleus
3) Cytokinesis –division of the rest of the cell (cytoplasm, organelles, cell membrane)
Interphase
- During Interphase:
Growth - Duplication of chromosomes - Growth
Cell takes in nutrients to build proteins
Duplicates chromosomes within the nucleus to create sister chromatids (joined by the centromere)
Interphase involves growth, cellular respiration, nutrient intake for protein building, and DNA duplicates for cell division, with sister chromatids joined by centromere.
Mitosis Stages
Prophase, Metaphase, Anaphase, Telophase (know in this order)
Prophase
In the first phase of mitosis, DNA condenses and becomes visible as chromosomes shorten and thicken, the nuclear membrane and nucleolus disappear, and centrioles move to opposite cell poles.
Metaphase
In the second phase of mitosis, chromosomes align in the middle of the cell, and spindle fibers form, attach to the centromere, and pull the chromosomes to the centre of the cell
Anaphase
In the third phase of mitosis, the centromere splits, sister chromatids separate into daughter chromosomes, and spindle fibers pull these daughter chromosomes to opposite ends of the cell.
Telophase
In the final phase of mitosis, chromosomes reach opposite cell ends, new nuclear membrane re-forms around daughter chromosomes, nucleolus re-appears, and cleavage furrow forms.
Cytokinesis
*Final stage of cell division
*Cytoplasm divides
*Two genetically identical daughter cells form
*Animal cell: cell membrane is pinched off in the middle at the cleavage furrow
*Plant cell: cell plate forms and develops into a new cell wall
What is cancer?
Cancer is cell division out of control
“Cancer” refers to a whole group of diseases (including leukemia –
cancer of the blood)
What is the difference between normal cells and cancer cells
-Normal Cells:
▪ Divide slowly
▪ Eventually die and are replaced
-Cancer Cells:
▪ Divide quickly
▪ Don’t die quickly
-Cancer cells build up (tumor)
What is a Tumour?
A tumour is any build-up of cells that continue to divide without giving any benefit to the body
With cancer, the bad cells crowd out the good cells and sometimes destroy them
Benign tumors
don’t harm the other cells
malignant tumors
interfere with or destroy other cells
Stages of a Tumour
Tumour starts on the surface of the organ
This cell has a mutation that makes it divide rapidly
The tumour steals nutrients in the blood from healthy cells
Cancer cells starts to invade other areas of the body (often lungs, bones, liver, brain)
The blood carries cancer cells to other areas of the body
Red Blood Cells
made in bone marrow
small
no nucleus
carries oxygen to body cells
removes carbon dioxide
lives 4 months
hemoglobin: protein in red blood cells, contains lots on iron
White blood cells (leukocytes)
larger than red blood cells
have a nucleus
protect or fight off disease/ infection
immune system
Leukemia cancer in white blood cells not all white blood cells are the same
lysosomes are prominent
Skin cells
largest organ in body
protects from: sun, bacteria, water loss (sweating)
Bone cells
lots of mitocondria
osteoblasts: build bone
osteoclasts: build/destroy old bone
osteocytes: produce osteoblasts
calcium will not stay in your bones prominently and will eventually diffuse into body cells
Muscle cells
lots of mitochondria
produces movement
improves posture
To work:
contract, flex, extend
3 different kinds of muscle:
smooth, skeletal, and cardiac
Sperm cells
made up of mostly mitocondria
have flaellum (tail)
helps with reproduction when the sperm cell fertilizes with the egg cell
Only lives 3 days
Fat cells
predominante organelle is vacuoles
provide energy
store nutrients (water, etc.)
provide warmth
Nerve Cells (neuron)
most produced before birth
in the brain and spinal cord
transmits signals to brain
axon: carries signal away from cell
dendritc: carries signal towards cell
What are common cancers
lung, prostate, breast
What causes cancer
- genes (only for some cancers {breast, ovarian, and colorectal})
- environment (carcinogens: factors that cause cancer eg. asbestos, certain chemicals, x-rays, uv rays)
- choices (sometimes we expose ourselves to carcinogens eg. tanning beds, smoking)
Lung Cancer (causes)
- 90% of lung cancer is associated with tobacco use
1 pack per day= 30% more likely to get lung cancer
Fighting Cancer (diet)
antioxidants: natural chemical compounds that bodys cells from damage
Found in tomato, berries, broccoli, garlic, green tea, leafy green vegetables
Diagnosing cancer
Imaging (CT, MRI, X-ray)
examining cells (biopsy)- the most important, only defining way, a sample of skin
early diagnoses are crucial for success in cancer treatment
Treatment of cancer
- Surgery (phsyical removal of tumor)
- chemotherapy (drug therapy to remove cells)
- Radiation (targeted radiation to kill cells)
- Bio-photonic, (tuning high-energy light for detection and treatment
