Key Words Flashcards
Active Transport
- low - high concentration
- it requires metabollic energy (ATP)
Bilayer
- membrane - consists of two layers of phospholipids
Carrier Protein
- Spans the phospholipid bilayer- binds to ions or molecules
CHange shape in order to move these molecules across membrane
Cell membrane
- selectively permeable membrane around cell - control entry and exit of materials
Cholesterol
- lipid
- important component of cell membrane - adds strength
- excess in blood leads to atheroma
Fluid mosaic model
- arrangement of various molecules of cell surface membranes
- fluid because individual phospholipid molecules can move relative to one another
- mosaic as the proteins vary in shape, size, and patterns
Glycolipid
Carbohydrate covalently bonded to a lipid
* act as recognition site
* help maintain stability of membrane and help cells attach to one another
Glycoprotein
- carbohydrate chain attached to a protein
- Act as recognition sites
- Help cells attach to each other and recognise one another
Partially permeable
- (semi-permeable)
- allows water and other small molecules
(nothing large like starch)
Permeability
- how permeable a substance is depends on size, polarity and charge of molecule
- if its small, non-polar and fat soluble = very permeable and can pass through cell membrane
Phospholipid
- Triglyceride - 1 fatty acid replaced with a phosphate molecule
- important in structure and functioning of a plasma membrane
Plasma membrane
- membranes consisting of a phospholipid bilayer found around and w/in all cells
- the cell-surface membrane is the plasma membrane that surrounds cells
Protein channel
- Protein spanning the phospholipid bilayer - form water filled tubes to allow water - soluble ions to diffuse across the membrane
Phospholipid bilayer
- barrier to dissolve substances
- centre is hydrophobic - doesn’t let water-soluble molecules (ions+polar substances)
- allows small non-polar molecules (CO2) to diffuse through
Intrinsic Proteins
what are they?
also known as?
- intergral proteins - embedded in phospholipid layer may/may not extend through both layers
- Channel + carrier proteins allow large, polar molecules and ions to pass through the membrane
attached to the bilipid layer
Peripheral proteins
- act as receptords + allow the cell to detect chemicals released from othercells - so they can respond
- inner or outer surface of phospholipid bilayer
attached to the bilipid layer
Glycoproteins
- proteins with carbs attached
attached to the bilipid layer
Glycolipids
- lipids with carbs attached
Cholesterol
where does it bind to + function?
- binds to phospholipid tails - make them pack together more closely =stability
Countercurrent flow
- flow of water over lamellae and flow of blood in them are in opposite directions
- keeps diffusion gradient to be maintained across the gill lamellae
Gill
where
- in body of fish, behind the head
gill filaments
- make up gills of a fish - stacked in a pile
Gill lamellae
- right angle to gill filaments - increase S.A of gills
Spiracle
- Tiny pores - allows gases to enter and leave tracheae (+water vapor to leave aswell)
- opened and closed by a valve
Tracheae
- large internal network of tubes in insects - w/ supported rings to prevent them from collapsing
Tracheoles
- These tubes extend from tracheae and extend thoughout all of the body tissues of the insect - allows atmospheric air tobe b rought directly to respiring tissues
somatic cell
or vegetal cell, is any biological cell forming the body of a multicellular organism other than a gamete, germ cell, gametocyte or undifferentiated stem cell. Somatic cells compose the body of an organism and divide through mitosis
germ plasm
Germplasm is the genetic material of an individual that may be transmitted, sexually or somatically, from one generation to another
Magnification
how much bigger compared to original
Resolution
how far apart two points can be before theyre seen as one
