Biology Chapter 4
What did Theodor Schwann conclude, and in what year?
In 1839, he concluded all animals have cells
What is plasma membranes purpose? (5)
Interacts with other cells, excretion, separation, security, gatekeeper
What is rough endoplasmic reticulum?
Interconnected tubes made of phospholipids that build proteins. Rough ER stays around the nucleus
What is DNA?
It carries genetic information
What is cytoplasm?
A jelly like fluid found within the cell, but without the nucleus. Helps with shape
What is RNA?
A very small piece of DNA being sent to the ER where proteins are made.
What are the three parts of the cell theory?
All living organisms are composed of one or more cells Cells are the basic units of structure and function in an organism Cells come only from the reproduction of existing cells
What does an enzyme do?
Assists chemical reactions inside a cell
List parts of plasma membrane and what they do.(5)
Cell-surface marker, cholesterol, receptor protein, enzyme, transport protein
What did Rudolf Virchow learn?
Cells come only from other cells
What are the two types of DNA?
Chromatin: long and thin, easy to read Chromosome: compact, preparing to divide
What is the purpose of plastids?
Contain their own DNA like, chloroplast and chromoplast
What does a nucleus do?
Control center, house and protect DNA
Name 5 parts of a prokaryote.
DNA Flagellum Ribosome Cell membrane Cell wall
What is inside a nucleus?
DNA, Nucleoplasm, Nuclear envelope
What is the purpose of cell wall?
For strength and support
What does a cell-surface marker do?
Glycoprotein that identifies the cell type
Describe the efficiency of cells based on size.
Groups of smaller cells can have the same volume as one large cell, but be much more efficient. This is because of a higher SA/V ratio. Small cells have space between to better get nutrients.
List 3 facts about eukaryotes.
Has a nucleus Has organelles Generally much larger in size than prokaryotes
What does a transport-protein do?
Helps substances move across a cell membrane
What did Matthias Schwann conclude, and in what year?
In 1838, he concluded all plants have cells
What is the formula for volume?
Length x Width x Height
What is the formula for surface area?
Length x Width x Number of sides
What is flagellum?
Long thin, strands that allow protists to move, they are microtubules
Name the three people who contributed to the cell theory.
Matthias Schleiden Theodor Schwann Rudolf Virchow
What is flagella?
Microtubules that are long and few, helps cells move
Why are mitochondria important to functioning of eukaryotic cells?
Mitochondria is like the battery of a cell. It provides every for all the functions of a cell. Mitochondria has its own DNA and can divide if the cell needs more energy. Muscle cells have lots of mitochondria while fat cells have fewer.
Are human cells prokaryotes?
No
List 4 facts about prokaryotes.
No nucleus No organelles DNA is one piece in the nucleoid region attached to the cell membrane 2/3 of the domains of life are prokaryotes (bacteria and archaea)
What is the plasma membrane made of?
Phospholipid bilayer polar phosphates, non-polar lipids
What is a nuclear envelope?
Plasma membrane around the nucleus
What are the three unique features of plant cells?
Plastids, cell wall, vacuole
What do proteins do?
Proteins are like little robots designed by the nucleus to accomplish whatever task must be done in a cell.
What does a receptor-protein do?
Recognizes and binds to substances outside a cell
Why can small cells exchange substances more readily than large cells?
Small cells have larger surface area to volume ratio. This means that with more surface area, things such as nutrients, oxygen, and carbon dioxide can readily pass in and out of the cells through its pores. If the volume to surface area ratio was smaller, the cell would be much less efficient in its tasks.
What is a vacuole?
Stores water and gives support to the plant
What is the cytoskeleton?
System of tunnels, filaments, and cables that provide a road system and give shape to a cell
What is the role of DNA in cells?
The DNA is the cells genetic information. This hereditary information contains instructions for the cells structure and function. Although DNA always remains in the nucleus, small pieces called RNA can be carried out to instruct ribosomes and ER on the construction of proteins
What is the Nucleolus?
The part in a nucleus where DNA is concentrated, also where RNA is made
Where are proteins built?
They are built in ribosomes and ER, and refined in the Golgi apparatus.
What are ribosomes?
They transport RNA and build proteins and are found in the nucleus, ER, and cytoplasm
What is the term for copying DNA?
Transcription
Describe the structure and function of the cytoskeleton.
Tunnels or microtubules made by tubulin hold things in place and guide things that move. Filaments or microfilaments made of actin help cells crawl and move. Cables or intermediate filaments anchor organelles and the nucleus, and keep the cells shape.
What are the three types of cytoskeleton?
Tunnels: Microtubules Filaments: Microfilaments Cables: Intermediate Filaments
What is Nucleoplasm?
What fills the nucleus, like cytoplasm
Larger cells have a _______ surface area:volume ratio.
smaller