5 Flashcards
independent variable
the cause of the dependent variable
dependent variable
outcome/effect of the experiement
what your measuring in the experiment
what makes red blood cells unique from other cells
they do not a nucleus
why is is the ovum larger than a red blood cell
red blood cells are small as they transport oxygen quickly in out and of the cell, whereas the ovum is not transported as much and contains half the genetic material of a new organsim, organelle and nutrients for growht, hence it is larger
Justify which cell(ova or red blood cell) would have a larger surface area to volume ratio with reference to cell size and cell shape.
Red blood cells would have a higher SA:V. They have a much smaller volume compared to the ovum and they have a biconcave disk shape which has a larger surface area compared to an almost spherical ovum.
when does the surface area to volume decrease
when size increases and when the shape becomes more spherical
why do cells and organelles tend to be more flat and small
higher surface area to volume to ratio
why do most biologist consider viruses as non living
bacteria are able to reproduce independently, whereas viruses are not.
bacteria have metabolic processes, whereas viruses do not
bacteria are composed of cells, whereas viruses are not
what is something that both bacteria and viruses do
evolve
how does the cristae increase the surface area of the membrane
because of its squiggly shape
Explain why the intestinal wall is made of many small cells, rather than just a few very large ones.
Small cells have a larger SA;V than larger cells. Cells that have a larger SA;V exchange more materials. The small intestine needs small cells as they will have a larger SA;V which increases the rate that nutrients in the small intestine like food and oxygen are absorbed and waste is removed
equation for aerobic celluar respiration
glucose + oxygen → carbon dioxide + water + energy
where are mitochondria found
only in eukaryotes, prokaryotes dont haveso instead they produce ATP on the surface ofthe cell membrane
The genetic material of prokaryotic cells is contained in
a circular chromosome and many small plasmids.
what happens in the cristae and why does there need to be a large surface area in the cristae
celluar respiration happens in the cristae and the greater the surface area, the more celluar respiration that can take place
difference between intregal, pheriphal and transmembrane proteins
intregal proteins are found deep in the bilayer
pheriphal proteins are found floating on the sruface of the memrbane
transmembrane proteins extend from the beginning to the end of the protein
The molecule that is lipid-based and regulates fluidity of the membrane is
cholestrol
what is chromatin
mixture of DNA and protein that forms chromosomes
what is the function of chromatin
makes chromosomes
where are chromosomes located
inside the nucleus
what are chromosones
made of proteins and a single strand of DNA that carries the genetic material from one cell to another
How is DNA stored
as a chromosome
difference between channel and carrier proteins
they are the same except carrier proteins close one side of the protein when a substance enters and the opposite side opens
What is electron transportation
a process part of cellular respiration that produces ATP
what do carbohydrates do
can help in sending signals and sticking cells together eg. involved in phospholipids sticking onto eachother
what can carbohydrates attach to
proteins and lipids
wwhat can carbohydrates attach to
proteins and lipids
what is the purpose of the control variable
tocreate a baseline where results can be compared
what is a plant cell composed of
cellulose
What are the 3 functions of the cell membrane
Gie the cell shape and structure
Confine internal contents into one place
Allows substances to enter in and out in a regulated manner
Why is the plasma membrane referred to as semi-permeable.
Small polar substances cannot enter the cell as it repels against the hydrophobic tails and therefore require carrier or channel proteins such as water
Large non polar and polar substances cannot enter the cell as they are too big and therefore require channel or carrier proteins such as glucose
Small non polar substances can pass through the membrane as they are tiny and do not repel the hydrophobic tails
Ions are charged and therefore cannot enter the plasma membrane
function of phospholipid
have a role in regulating transport across membranes, and are the structure in which proteins and carbohydrates are embedded
why does the plasma membrane contain receptors
for cell recognition and to recieve signals from other cells
why are proteins embedded in the bilayer
Transport of molecules such as protein channel or carriers
Communication: allows cells to receive signals
what extends outside the cell and what do they do
glycolipids are chains attached to lipids, whilst glycoproteins are chain attached to proteins
these proteins
assist in self recognition to avoid attack from the immune cell and are involved in cell communication
what is and what does chloestrol do
A lipid steroid which regulates fluidity of the plasma membrane
when the temperaure increases cholestrol keeps the plasma membrane intact and prveents it from falling apart whereas when the termpature decreases it prvents phoshoplipids from jjoining too close together to allow for the exchange of substancees
the fluid mosiac model explains that
Molecules that make up the plasma membrane are not fixed in one place
The ‘patchwork’ of proteins embedded represent a mosaic model.
The plasma membrane allows certain substances in and out of the cell based on
size, charge and concentration graident
explain the factors the effect diffusiion
Concentration gradient.
The diffusion distance.
Surface area.
Physical barriers.
the movement of water can
impact the size and shape of the cell
