Cell Structure + Transport P1 Flashcards
Diffusion
-A net movement of particles from an area of high to low concentration. —> higher the temp, faster the diffusion
-Doesn’t use energy = passive
-Usually results in an equilibrium.
(alveoli to lungs, stomata of leaves)
Osmosis
-A net movement of particles across a partially permeable membrane from an area of high to low concentration
- Doesn’t use energy = passive
-Solute does not cross the membrane (only water).
(root hair cells—> water absorption from soil)
Active Transport
-A net movement of particles from an area of low to high concentration. SUGARS
-Does use energy as particles are moving against the concentration gradient.
(root hair cells, kidneys)
How do you work out the percentage change in mass?
change in mass divided by original mass x 100
Magnification equation triangle/ total magnification equation
I at the top
A on the bottom left, M on the bottom right
(I = image size, A = actual size, M= magnification).
total magnification = eyepiece magnification x objective lens
Cell cycle order (mitosis) + uses
1- DNA replication and cell growth ->chromosomes replicate and so does everything else in cell, line up in centre of cell
2- Mitosis -> chromosomes pulled apart to poles of cell
3- Cell division -> cells and cytoplasm divide to create two genetically identical daughter cells
uses:
- growth
- repair to damaged tissues
- replacement of worn-out cells
Eukaryotes/ic
-Plants and animals
=cells which contain their genetic material enclosed in a nucleus
-0.1-5.0 um
Prokaryotes/ic
-Bacteria
= cells which do not contain their genetic material enclosed in a nucleus
- much smaller
-10 - 100 um (no mitochondria, chloroplasts or nucleus)
Sub-cellular structures
Structure inside a cell
Animal cell’s sub-cellular structure
nucleus, ribosomes, mitochondria, cell membrane, cytoplasm and vacuole
Nucleus
The control centre of the cell which contains chromosomes which contain the cells genetic material.
Cell membrane
Separates the interior from the environment. It is selectively permeable which means it chooses what goes in and out.
Mitochondria
Where aerobic respiration takes place -> requires energy needed for active transport
Cytoplasm
Where chemical reactions occur.
Ribosomes
Responsible for synthesising proteins.
Plant cell’s sub-cellular structure
nucleus, ribosomes, mitochondria, cytoplasm ,cell membrane,
chloroplasts , cell wall and a vacuole.
vacuole
A fluid-filled sac that stores water.
Chloroplasts
Contains chlorophyll, which is needed for the process of photosynthesis.
Cell Wall
Increases the structural strength of the cell as it is made from cellulose
Bacterial Cell’s sub-cellular structure
cell wall, cell membrane, plasmid, cytoplasm and a flagella.
Plasmid
A small ring of DNA.
Flagella
A whip-like structure used for movement.
Cell differentiation/ specialisation
The process where a cell develops new sub-cellular structures to let it perform a specific function.
-when this happens the cell becomes specialised.
Zygote
A single new cell, formed by the fusion of an egg and sperm
Where do embryonic stem cells and adult stem cells come from?
embryonic –> human embryos
adult –> adult bone marrow