Cell Biology - Cell Structure And Cell Division Flashcards
what are eukaryotic cells
animal and plant
what is the cytoplasm
gel like substance where most chemical reactions happen. contains enzyme to control reactions
what is the cell wall made of
cellulose
what does the permanent vacuole contain
cell sap which is a weak solution of sugar and salt
what are chloroplasts
contains chlorophyll which absorbers light needed for photosynthesis
what are rings of DNA in bacteria cells called
plasmids
give example of what light microscope allows to see
individual cells and large sub cell structures such as the nucleus
give an an example of what an electron microscope allows us to see
internal structure of mitocndria, ribosones, plasmids
equation for magnification
image size/real size
order millimetre, nanometre and micrometre in descending order
millimetre, micrometre, nanometre
how do you convert micrometre to nanometre
x 1000
what is differentiation
the process that a cell changes to become specialised
what are the cells that differentiate in mature mammals usually used for
repair and replacement
how is a sperm cells specialized
long tail and streamline head to hep it swim
lots of mitochondria to provide energy to swim
enzymes in head to digest through cell membrane
how is a nerve cell adapted for its function
long
branched connections
how are muscle cells adapted for their function
long so they have space to contact
lots of mitochondria to provide energy for contraction
how are root hair cells adapted for their function
hairs that stick out into the soil that give large surface area
how many pairs of chromosomes do humans have
23
what are chromosomes made up of
long lengths of DNA which is coiled up
what are genes
short sections of DNA
what is mitosis
when a cells reproduces itself by splitting to produce 2 identical offspring
what’s the point in mitosis
growth, development and replacing cells
explain the growth and replication stage of mitosis
cell grows and increases amount if subcellular structures
duplicates DNA to form x shaped chromosomes. each arm is a duplicate of the other
what happens during mitosis
chromosomes line up in centre of cell and the cell fibres pull them apart
membranes form around each sets of the chromosomes
cytoplasm and cell membrane splits
identical daughter cells are produced
explain the process of binary fission
strands of dna and plasmids replicate
the stands of dna move to oppersite ends of the cell and the cytoplasm begins to divide and form a new cell wall
two daughter cells are formed w one copy of the dna stand and a random amount of plasmids
a bacteria cell has a mean division time of 30 minuets. How many cells will it produce in 150 mins
150/30 = 5 divisions
2 to the power of 5 = 32 cells
what are stem cells
undifferentiated cells that can replicate or differentiate
where are stem cells found in adults
bone marrow bu these cannoot turn into any type of cell only certain ones such as red blood cells
how can stem cells be used to treat diabetes
turned into insulin producing cells
what is therapeutic cloning
embryo could be made to have the same genetic material as the patient so wouldn’t be rejected
what are the risks of using stem cells in medicine
may be contaminated with a virus when grown in a lab
embryos are used which could be a potential human lfe
what is an argument against not using stem cells from embryos
they are usually unwanted ones that wouldn’t have been used anyway.
where are stem cells found in plants
meristems which is the part of the plant where growth occurs
plant stem cells can be used for producing clones of plants quickly and cheaply which is used for:
growing crops that have a desired feature
growing more plants of a rare species so they dont get wiped out
