cells unit 1 Flashcards
cell membrane
controls cell entry and exit
cytoplasm
watery substance found in cells where all the chemical reactions take place
nucleus
controlls cell activity and contains all the genetic info
chloroplast
found in green plant cells and contains chlorophyll. where photosynthesis takes place
vacule
a watery solution that provide structure to the cell
cell wall
outer cover of the plant cell that provides structure and shape
mitchochondrion
Cylindrically-shaped structure found in varying numbers within the cytoplasm of cells that is the site of energy released in aerobic respiration
ribosome
site if protein synthesis
active transport is
the movement of substances in cells against the concentration gradient
passive transport is
known as diffusion and osmosis and does not require energy
turgid is
When the water
concentration is higher
outside than inside
water moves in and the
cell bursts releasing its
contents
plasmolised is
Higher water
concentration inside
the cell so water
moves out by
osmosis causing the
cell be become
plasmolysed
DNA Is shaped like a
double helix or twisted ladder
the 4 bases in DNA
- A denine
- T hymine
- G uanine
- C ytosine
Base A can only pair with
- T hymine
base C can only pair with
- G uanine
catalysts
speed up chemical reactions without altering the results
M RNA
carries a complimentary copy of the genetic code from the DNA
enzyme
catalase chemical reactions in a cell
hormones
chemicals that act as messengers and affect how living things develop and behave
antibodies
large molecules that help decent against infections
Haemoglobin
transport of oxygen in the blood stream
daughter cells are
genetically identical to parents cells
how many chromosome sets do humans have
46 - 23 pairs
what is the diploid number
the total number of chromosomes in a cell
plant cell
animal cell
bacteria cell
fermentation
respiration without oxygen
selectively permiable
small molecules such as carbon dioxide, oxygen and water can pass across easily but larger molecules like proteins cannot
passive transport
molecules move down a concentration gradient
also known as diffusion
osmosis
example of passive transport. it is the diffusion of water molecules
from a higher concentration to a lower one across selectively permeable membrane
active transport
moving against the concentration gradient