science quiz Flashcards
what is the nucleus?
- largest organelle
- center/middle of cell
- controls growth and reproduction of the cell
what is the nuclear membrane?
- protects the nucleus
what is the nucleolus?
- center/middle of the cell
- DNA (chromosones)
- makes ribosomes/protien
what is the centrioles?
- long tubules
- invloved in cell division
what is the cytoplasm?
- clear, thick, gel-like fluid
- all the material between a cell membrane and the nucleus
what is the cell membrane?
- semi-permeable
- several different protiens used for various functions
what is the cell wall?
- very rigid and thick
- only found in plant cells
- gives a difined shape
what is the vacuoles?
- vacuoles in plant cells are bigger
- store nutrients
- maintains internal fluid pressure and store waste products
what are lysosomes?
- digest the waste
- work swiftly
what are ribosomes?
- floating in cytoplasm or on endoplasmic reticulum
- produces protien/synthesizers
what is the endoplasmic reticulum?
- 2 types: rough and smooth
- synthesizing and transporting protiens and other carbohydrates
what is the golgi apparatus?
- has lots of mucus such as intestine or lungs have many golgi bodies
- collecting, proccessing and packaging materials to be removed from the cell
what is the mitochondria?
- powerhouse cell
- known as the powerhouse of the cell acts like a digestive system that takes in nutrients, breaks down and creates energy
- glucose+oxygen —> carbon dioxide+H2O+energy
what is the chloroplast?
- contains chlorophil and gives plants the green colour
- allows plants to absorb light energy (photosynsthesis)
- carbon dioxide+water —> glucose+oxygen
what are red blood cells?
- small
- no nucleus
- carries oxygen to bodies cells
- life span is 4 months
what are white blood cells?
- larger then red blood cells
- nucleus
- protection (fight off disease/infections)
- immune system
what are skin cells?
- largest organ in the body
- protection (sun, bacteria, water loss)
what are bone cells?
- 3 types: osteoblasts, osteoclasts, osteocytes
osteoblasts: builds bone
osteoclasts: removes/destroys old bone
osteocytes: produces osteoblasts - calcium eventually diffuses into body cells
what are muscle cells?
- produces movement
- improving posture (contract, flex/extend)
- 3 types: smooth muscle, skeletal muscle, cardiac muscle
what is the sperm cell?
- mitochondria (tail: flagelum)
- reproduction (fertilize egg cell)
- the lifetime of a sperm cell is 3 days
what are fat cells?
- energy
- nutients (storage)
- warmth (insulation)
- vacuoles
what are nerve cells?
- most produced before birth
- spinal cord
- transmits signals to brain
- axon: carries signals away
- clendrite: brings signals towards cell
what is the stage of interphase?
- cellular respiration
- cells take in nutrients to build protiens
- DNA duplicates in preparation for cell division (sister chromatids joined by centromere)
- G1, G2, S (synthesis)
what is the stage of prophase?
- first phase of mitosis
- DNA condenses and becomes visible as chromosomes (shorten and thicken)
- nuclear membrane and nucleolus disappears
- centrioles move to opposite poles of the cell
what is the stage of metaphase?
- second phase of mitosis
- centromere line up in the middle of the cell (equatorial plate)
- spindle fibers form, attach to the centromere and pull chromosomes into the middle of the cell
what is the stage of anaphase?
- third phase of mitosis
- centromere splits and sister chromatids seperate into daughter chromosomes
- spindle fibers pull daughter chromosomes to opposite ends of the cell
what is the stage of telephase?
- final phase of mitosis
- daughter cells
- chromosomes reach the opposite ends of the cell
- new nuclear membrane re-forms around each group of daughter chromosomes and the nucleolus also re-appears
- cleavage furrow forms
what is the stage of cytokinesis?
- final stage of cell division
- cytoplasm divides
- animal cell: cell membrane pinched of in the middle at the cleavage furrow
- plant cell: cell plate devolopes into cell wall
what is cancer?
- cancer is a cell division out of control
- “cancer” refers to a whole group of diseases (including leukemia, cancer of the blood)
what are normal cells?
- they divide slowly
- eventually die and are replaced
what are cancer cells?
- they divide quickly
- they dont die quickly
- cancer cells build tumors
what is a tumour?
benign: dont harm other cells
malignant: interfere with or destroy other cells
what is metastasis?
- the spreading of cancer cells (cells spread)
what causes cancer?
- carcinogens: factors that cause cancer
ex. asbestos, certain chemicals, X-rays, UV radiation
what are the types of diagnosis for cancer?
- imaging (CT, MRI, X-ray)
- Examining cells (biopsy)
- early diagnosis is crucial for the sucess of the cancer treatment
what are the types of treatments for cancer?
- surgery (physical removal of tumour)
- chemotherapy (drug therapy to kill cells)
- radiation (targeted radiation to kill cells)
- bio photonics (using high energy light for detection and treatment)
what are Prokaryotic cells?
- cells without a nucleus
- only organelle in prokaryotic cells are ribosomes
what are Eukaryotic cells?
- cells that have a nucleus
- other cells besides the nucleus
What are the differences between animal and plant cells?
- animal cells have centrioles, centrosomes and lysosomes and plant cells do not
- plant cells have a cell wall, chloroplasts and plastids used for storage, and a large central vacuole and animal cells do not
what is Chromatin?
the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and DNA.
what are Chromosomes?
A structure found inside the nucleus of a cell. A chromosome is made up of proteins and DNA organized into genes.
what are Centrioles?
it organizes microtubules that serve as the cell’s skeletal system. They help determine the locations of the nucleus and other organelles within the cell. Located in the cytoplasm of animal cells near the nuclear envelope.
what are Spindle fibres?
it equally divides the parental cell into two daughter cells
what is the Centromere?
helps the cell divide up its DNA during division
what are Sister chromatids?
identical copies of a chromosome
what are daughter chromosomes?
the result of sister chromatids splitting up
what is DNA?
a molecule that contains the genetic code that is unique to every individual.
what are Diploid cells?
- a cell that contain two copies of each chromosome.
what are Haploid cells?
a cell that contains a single set of chromosomes.
what are Specialized cells?
cells designed to carry out a particular role in the body
ex: nerve cells, sperm cells, egg cells
