"All cells come from other cells that already exist" is one of the main ideas of this theory.
What is the cell theory?
This organelle holds the cell's DNA and controls the cell's activities.
What is the nucleus?
Bacteria are this type of cell, which does not have a nucleus.
What is a prokaryotic cell?
The cell membrane is made of two layers of these molecules, which make it flexible.
What are lipids? (a lipid bilayer)
Fill in the missing level: cell, tissue, ______, organ system, organism.
What is an organ?
This scientist looked at a thin slice of cork under a light microscope and was the first to call what he saw "cells."
Who is Robert Hooke?
These organelles release energy that the cell can use.
What are mitochondria?
Plants and animals are made of this type of cell, which keeps its DNA inside a nucleus.
What is a eukaryotic cell?
When particles move from a high concentration to a low concentration without using energy, this process is happening.
What is diffusion?
The digestive system is one of these, a group of organs that work together to do one specific job.
What is an organ system?
This type of microscope can show a 3-D picture of the outside of a cell.
What is a scanning electron microscope?
These organelles contain enzymes that break down lipids, carbohydrates, and proteins.
What are lysosomes?
Plant cells have these two structures that animal cells do not.
What are the cell wall and chloroplasts?
This is the diffusion of water across a membrane.
What is osmosis?
The circulatory system includes the heart, blood vessels, and this.
What is blood?
This type of microscope can be used to look at living cells and shows their true colors, but it can’t magnify as much as an electron microscope.
What is a light microscope? (A compound light microscope also works.)
This organelle changes, sorts, and packages proteins so they can be sent where they need to go.
What is the Golgi apparatus?
These tiny organelles help organize cell division in animal cells.
What are centrioles?
This type of transport needs energy from the cell and moves particles from a low concentration to a high concentration.
What is active transport?
Mature red blood cells cannot repair damaged proteins because they do not have these two things.
What are a nucleus and ribosomes?
A scientist wants to see the inside of a cell in very thin slices at very high magnification. She needs this type of microscope.
What is a transmission electron microscope?
This organelle is filled with fluid, and in plant cells it helps keep the cell stiff so the plant can hold up its leaves and flowers.
What is the vacuole?
This organelle changes sunlight into chemical energy. Animal cells do not have it because animals get their food by eating.
What is a chloroplast?
In this kind of solution, the concentration of solute particles is the same inside and outside the cell, so there is no overall movement of water.
What is an isotonic solution?
A leaf is an organ in a plant. It is made of groups of similar cells that work together to do one job. These groups are called this.
What are tissues?