CELL STRUCTURE Flashcards
All cells are surrounded by a selective barrier called what
plasma membrane also known as a cell membrane
what do we find inside the cell barrier
a jellylike semi fluid called cytosol (cytoplasm) in which cell organelles are suspended
name some cell organelles
nucleus mitochondria ribosomes Golgi apparatus vacuole they serve diff functions
what are organelles
they are specialised structures found inside living cells that perform specific functions for the cell
what is a cell membrane
it encloses the cell.
and it forms the outer boundary of the cell
surrounds the contents of the cell
what is a cell wall
extracellular structure of plant which distinguishes the from animal cells
it s a wall that surround the cell on the outside
why do plant cells have a cell wall but animals don’t
the cell will protects and support the cell
animals do not need a cell wall because organisms are protected and supported ut their skeleton
what is a cytoplasm
it is a jelly like substance that fills the cell
it consist of water with other components which either dissolve or suspend in it
what is a nucleus
it is a round organelle that is surrounded by a nuclear membrane and it contains the DNA of the cell
what is a mitocondria
it is the organelle in the cell where cellular respiration takes place
what is respiration
the process in which glucose breaks down in the presence of oxygen in the cells of organisms , to produce carbon dioxide , water and energy
what is a chloroplast
found in plant cells
site for photosynthesis
contains the green pigment called chlorophyll
absorbs the light energy from the sun and converts it into energy rich sugars called glucose
sugars produced store as starch
what is photosynthesis
process in which plants use chlrorphyll to convert radiant energy into sugars when carbon dioxide reacts with water also producing oxygen in the process
wat is a vacuole
fluid filled sacs that are surrounded by the membrane
how many vacuoles do animals and plants have
animals - one or two small vacuoles or no vacuoles at all
plants - have one or two large vacuoles which store substances like sugars ,salt ,water
what are the differences between a plant cells and animal cell
- plants cells have cell walls and animals cells don’t
- plants have a regular shape due to rigid cell wall – animals cells have an irregular shape
- plants cells have a large vacuole – animals cells have a small vacuole or non at all
- plants cells have chloroplast which enables them to make her own food –animals cells don’t have chloroplast and therefore are unable to make their own food
what the similarieties between a plant cells and a animal cell
dddd
what is the function of a cell membrane
to control the movement of materials into and out of the cell
it is selectively permeable - it does not allow certain substances to enter the cell
what is the function of a cell wall
to protect the plant cell,
to give it or maintain the shape of the cell
to prevents excessive uptake of water
what is a cell wall made up of
made up of cellulose which is a tough substances which helps it stand upright
what is the function of a cytoplasm
to provide a liquid medium for chemical reactions to take place
what is the function of the nucleus
it houses chromosomes which are made of chromatin (DNA and proteins )
IT contains deoxyribonucleic acid (DNA) of organism
DNA contains the info that’d determines the organisms inherited characteristic
nucleus controls all cell activities
what is the function of the mitochondria
it is the site for respiration
energy is released from glucose in the process of respiration
this energy produced from respiration is need by the cell to carry out it specific function
what is the function of the vacuole
used to store substances that can be used by cell
aslo functions in waste disposal ad water balance
