YR11 - Topic Test 1 - Cells, Moving Through Plasma Membrane Flashcards
cells
- they are the basic unit of all living things
- they come from pre-existing cells
- smallest living organisational unit
prokaryotic cells vs eukaryotic cells
prokaryotic cells have no nucleus circular DNA and no membrance bound organelles (bacteria) whereas eukaryotic cells have a nucleus, linear DNA and membrane bound organelles (animals and humans)
nucleus
contains DNA and controls cells activity
rough e.r.
controls what goes in and out of the cell, produces proteins
smooth e.r.
makes cellular products like hormones and lipids.
mitochondria
where aerobic respiration takes place, converts ATP into glucose, this process is known as respiration
ribosomes
where protein synthesis occurs
golgi apparatus
modifying, sorting and packaging of proteins for secretion. It is also involved in the transport of lipids around the cell, and the creation of lysosomes
chloroplast
found in plant cells. Contain chlorophyll that absorbs light for photosynthesis.
large vacuole
found in plant cells. Contain a fluid called cell sap Stores fluids, nutrients and waste.
cell wall
found outside the cell membrane in only plant cells and provides support for the cell
similarities plant vs animal cells
vacuoles, cell membrane, nucleus, mitochondria, cytoplasm, endoplasmic reticulum, ribosomes, golgi body
differences plant vs animal cells
vacuoles are noticeably bigger in a plant cell, plant cells have a cell wall and chloroplast
how does the shape of a plant cell differ from that of an animal cell?
a plant cell has a cell wall which helps it maintain a rigid structure whereas an animal cell has no cell wall
light microscope
uses light and a system of lenses to magnify the image
electron micropscope
an object is viewed using an electron beam instead of light. this allows us to see structures in far more detail
difference between light and electron microscope
electron microscopes allow us to see structures in far more detail than is possible using a light microscope
phospholipids
a fat-like substance, usually based on glycerol. Phospholipids are essential components of cell membranes. They are involved in the uptake of fats and fatty acids from the products of digestion
lipid bilayer
(or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells.
transport proteins (carrier proteins)
a transport protein that changes shape when molecules bind to it, so that the molecules can pass through the plasma membrane. they take part in facilitated diffusion and active transport
channel proteins
a transport protein that molecules do NOT usually bind to. they allow specific molecules to pass through the plasma membrane, and are used in facilitated diffusion.
cholesterol
a steroid lipid found in most body tissues. it is an important component of cell membranes in animals and is used to form other steroid compounds.
plasma membrane structure
cholesterol, channel and carrier proteins, carbohydrate chain, glycoprotein, cytoskeleton filaments etc.
simple diffusion
Simple diffusion is the process by which solutes are moved along a concentration gradient in a solution or across a semipermeable membrane from a high concentration to a low concentration