Chapter 7 Study guide, Biology 9th grade

What are the 3 statements of the cell theory?
1 All living things are made of cells
2 All cells come from other living things
3 the cell is the most basic unit of life

What is the difference between prokaryotic cells and eukaryotic cells?
Prokaryotic- No nucleus. DNA floats around the cytoplasm. Has bacteria
Eurokaryotic- has a nucleus

prokaryotic cells
Cell with NO nucleus, very simple, single loop of DNA (nucleosome), no cellulose,been around for millions of years. Example: Bacteria

Eukaryotic cells
Cell with NUCLEUS, membrane-bound organelles, very complex. Examples: Plant cells, animal cells, fungi

the powerhouse of the cell.this means that they help produce the energy needed to live

cell membrane
A cell structure that controls which substances can enter or leave the cell.

Maintains cell shape

A small, round cell structure containing chemicals that break down large food particles into smaller ones.

A system of membranes that modifies and packages proteins for export by the cell

Brain of the cell

Short hairlike projection that produces movement

Water based jelly-like substance outside the nucleus

What are the differences between plant and animal cells?
Plant cells have a cell wall and chloroplast

Selectively permeable
a property of cell membranes that allows some substances to pass through, while others cannot
Example of one is the cell membrane

Passive transport
The transportation of molecules across a plasma membrane without using energy. Example- diffusion and osmosis

Active transport
The movement of molecules across the cell membrane that requires the cell to use energy. Moves the molecules from lower to higher concentration