Unit 1 - Cell biology Flashcards
what do unicellular and multicellular mean?
unicellular - single celled
multicellular - multiple cells
what is the function of the cell membrane and what cell types is it found in?
it controls the entry and exit of materials into and out of the cell
found in all cells
what is the function of the cell wall and what cells are they found in?
they are a rigid structure around a cell, giving shape and support. they are made of cellulose and are freely permeable.
found in fungi, bacteria and plant cells.
what is the function of the nucleus and what cells are they found in?
controls all cell activities and contains genetic material
found in animal, plant, fungi
what is the function of the chloroplast and what cells are they found in?
site of photosynthesis. contains chlorophyll to absorb light energy.
plant cells only
what is the function of the mitochondrion and what cells are they found in?
site of aerobic respiration. where the cell produces most of its energy in the form ATP
found in animal, plant, fungi
what is the function of the vacuole and what cells are they found in?
they contains cell sap
found in plant, and fungi cells
what is the function of the ribosome and what cells are they found in?
they are the site of protein synthesis
they are found in all cells
what is the function of the plasmid and what cells are they found in?
they are a circular structure containing DNA
found only in bacteria
what is the function of the cytoplasm and what cells are they found in?
they are the site of chemical reactions
they are found in all cells
name all the cell structures in an animal cell?
nucleus, cell membrane, mitochondria, cytoplasm, ribosome,
name all the cell structures in a plant cell?
vacuole chloroplasts cell wall cell membrane mitochondria ribosomes nucleus cytoplasm
name all the cell structures in a fungal cell?
nucleus mitochondria cell membrane cell wall vacuole ribosomes cytoplasm
name all the cell structures in a bacterial cell?
ribosomes plasmid DNA capsule cell wall cell membrane cytoplasm
describe cell membranes?
all cells have a cell membrane which allows molecules to enter and exit and the cell
it is selectively permeable, allowing only small, soluble molecules such as water, and oxygen to pass through.
what are the two main components of the cell membrane?
phospholipids and proteins
why does there have to be a double layer of lipids?
so the phospholipids don’t get there tails wet.
when does passive transport occur?
it occurs when molecules or a substance move down a concentration gradient, and it doesn’t require energy
what is diffusion?
diffusion is the passive process where molecules move from an area of high concentration to an area of low concentration, down a concentration gradient until they are spread evenly
what is a concentration gradient?
a concentration gradient is the difference in concentration between two substances
why is diffusion important?
diffusion is important to cells as it allows an uptake of raw materials and exit of waste materials
what molecules can move through passive transport?
in = oxygen, amino acids, glucose out = Carbon dioxide, water and urea
what is osmosis?
the movement of water molecules from an area of high water concentration to an area of low water concentration through a selectively permeable membrane. it does not require energy and occurs down a concentration gradient.
what conditions do you need for an animal cell to shrink?
the water concentration outside the cell would need to be lower so the water would diffuse outside the cell causing it to shrink
what conditions do you need for an animal cell to burst?
the water concentration outside the cell would need to be higher so the water would diffuse into the cell causing it to burst
what conditions do you need for a plant cell to become turgid?
the water concentration outside the cell would need to be higher so the water would diffuse into the cell causing it to become turgid
what conditions do you need for a plant cell to become plasmolyzed?
the water concentration inside the cell would need to be higher so the water would diffuse out of the cell causing it to become plasmolyzed.
What is active transport?
active transport occurs when molecules and ions move from a lower concentration to a higher concentration. this occurs against the concentration gradient and therefore requires energy
proteins in the membrane help pump these ions across the membrane during active transport