Cells and Their Organelles
At what level of organization does life began?
Cellular level or the cell is the basic unit of life
what characteristics are shared by most cells
Have membrane-bound organelle, a nucleus, contain cytoplasm, are enclosed by a membrane, and have a nucleus, and are microscopic.
what organelle breaks down and recycles worn-out cells?
Lysosomes
Nucleolus
Makes ribosomes
Would it be accurate to say a chloroplast makes energy for a plant cell?
No, because chloroplasts transfer sun's energy, not make it themselves
chloroplast are found in what type of cells?
Plant cells
Microtubules
Provide support to cell during cell division "mitosis"
Mitochondria
take food and converts to energy for cells
in what ways are cells similar to atoms?
they are both basic building blocks
Rough ER
transports materials through the cell and produces protein
Explain what mitochondria do and why evidence suggest that they might have descended from free-living prokaryotes in the evolutionary past.
Supply energy to the cell. They convert molecules from food into usable energy. They have their own ribosomes and DNA unlike the prokaryotic cells.
Describe the structure of the nucleus.
The nucleus is surrounded by a double membrane with pores that connect its interior to the cytoplasm. DNA and the nucleolus are located inside the nucleus.
Golgi
both, modifies and packages proteins
Ribosomes
both, Makes proteins
cytoplasm
both, gelatin like feeling that is mostly helps suspended the organelles
What surrounds all cells?
cell membrane
The largest organelle in plants is the ____
central vaculole
centrioles are found at the center of the ______ how do they help the cell?
centrosome, makes microtubule leaks and gives Provide support to the cell during cell division
What pigment traps the energy?
chlorophyll
Nucleus
controls cellular function ("brain" of cell)
Chloroplast
convert sun's energy to food (photosynthesis)
Where are organelles located?
cytoplasm (outside the nucleus)
Lysosomes
digest food and old cell parts
How are eukaryotic cells different from prokaryotic cells?
eukaryotic cells have a distinct nucleus containing the cell's genetic material, while prokaryotic cells don't have a nucleus and have free-floating genetic material instead
how did the improvements in the microscope help scientists form the cell theory?
improvements allowed scientists to see cells in greater and greater detail and enable them to discover cells in all types of living matter.
Where is DNA found inside a cell?
inside the nucleus
Smooth ER
makes proteins and lipids that will be exported by the cell
Give 3 jobs for smooth ER.
makes proteins, controls the Calcium level in muscles, and detoxifies (poisons, alcohol, and drugs)
rough ER is connected to the ______ membrane and the ______
nucleus, smooth ER
Define the following terms organelles and cytoplasm
organelles- a specialized part of a cell having some specific function; a cell organ. cytoplasm- the cell substance between the cell membrane and the nucleus, containing the cytosol, organelles, cytoskeleton, and various particles.
In what way are lysosomes, vesicles, and the central vacuole similar?
All are membrane-bound organelles that store or separate certain substance
Nuclear pores
pathway for substances to move from nucleus to cytoplasm
What two things make up the cell membrane?
phospholipids and embedded proteins
according to the cell theory what is required for an object to be considered alive
-composed of cells -Responds and adapts to the enviornment -uses energy -grows and reproduces
Describe how the endoplasmic reticulum, mitochondrion, and Golgi apparatus are structurally similar.
All are composed of membrane-enclosed chambers. The surface area of each is greatly increased by folds and layers.
What process takes place inside chloroplasts?
photosynthesis
the additional layer is found around the outside of plant cells and bacteria?
plant cells have a cell wall but not bacteria
cell wall
plant, Provide support and structure to the cell
the cell membrane is also called the ______________ membrane?
plasma
nuclear membrane
processes substance to allow in any of nuclens
the process of making proteins is called?
protein synthesis
Centrosome
provides micro tubeless which provide support during cell division "mitosis"
where are proteins made in a cell?
ribosomes
central vacuole
stores water, digest food and waste
what is the energy for this process?
sunlight
Food, water, and wastes are stored inside ________.
vacuoles
Do all cell need ribosomes?
yes(so the cell can get protein)
explain the three major principles of cell theory in your own words
-call all organisms are made of cells -all existing cells are from pre-existing cells -the cell is the most basic unit of life
The word organelle is a diminutive, or "tiny," form of the Latin word for organs of the body. How is an organelle like a tiny organ
An organelle is like a tiny organ because a tiny organ has its own functions and methods in which it knows how to preform its function inside the body which is similar to an organelle because it has its own functions and methods also.
how are the nucleus and a vessel similar and different in structure and function
Both are membrane-bound compartments that store and separate certain materials. The nucleus is an almost permanent structure protected by a double membrane bilayer, whereas a vesicle is a temporary organelle.
What similarities do mitochondria and chloroplasts share?
Both membrane bound organelles have their own DNA and help make energy available to the cell.
DNA coils tightly during Division and assembles into vision______
Chromosomes
proteins made by rough ER travel to the Golgi in sacks called ____. Golgi____ and _____ proteins for export out of the cell.
Cistern, modifies, packages
How do the cytoskeleton and the cytoplasm contribute to a cell's shape?
Cytoskeleton has microtubules (long hollow tubes) which give the cell its shape and act as tracks for movement of organelles. The cytoplasm fills the space between the nucleus and the cell membrane.
Medicine, alcohol, and many drugs are detoxified in liver cells. Why do you think the liver cells of some people who abuse alcohol and drugs have an increased amount of smooth ER?
Increased amounts of smooth ER in the livers cells suggests that the cells have responded to increased amounts of toxins by producing more smooth ER to handle the processing.
Suppose a certain poison kills human cells by blocking pores in the nuclear membrane. Explain why it would or would not kill bacteria.
It would not kill bacteria because bacteria do not have a nucleus, so there are no nuclear pores to be blocked.
If you were looking through a microscope at an unknown cell, how might you determine whether itwas a plant cell or an animal cell?
Look for cell walls and chloroplasts (plant cell features) or centrioles (animal cell features).
Digestion takes place inside _________ containing _______.
Lysosomes, digestive enzymes
You know that many organelles are involved in protein production. Briefly explain where proteins are made, modified, and packaged within a cell.
Proteins are made in ribosomes which are located in the rough endoplasmic reticulum. They are then sent to the golgi apparatus where they are then modified and packaged.
How does rough ER differ from smooth ER?
Rough ER transports and makes proteins Smooth ER makes proteins and lipid for export
explain the structure and function of the mitochondria
Supplies energy to a cell by releasing the energy stored in food molecules. The outer membrane surrounds a highly folded inner membrane where the chemical activity occurs.
how was the development of cell theory closely tied to advancements in technology?
The cell theory depended on the invention of microscopes that allowed scientists to see cells.
what function does the cell wall perform in a plant
The cell wall protects, supports, and shapes a plant cell, and regulates what moves into the cell. The cell walls of multiple cells can help support the entire plant.
What problems might a cell experience if it had no cytoskeleton?
The cell would be disorganized. It would be weak and might fall apart. The cell would also be unable to move, divide, and transport organelles.
What are the functions of the cytoskeleton?
The cytoskeleton supports and shapes thecell, positions and transports organelles,provides strength, assists in cell division,and aids cell movement.
what is distinctive about the nuclear membrane? why is it described as an envelope?
The nuclear membrane, also called the nuclear envelope, is a double membrane layer that separates the contents of the nucleus from the rest of the cell. It is found in both animal and plant cells.
what is meant by semipermeable?
allowing some substances to pass into the cell and blocking others
Centrioles are found inside what type of cell?
animal cells
why did it take so long after cells were discovered for the cell theory to be developed?
biologist begin to organize information about cells into a unified understanding the three observation were combined to form a basic theory about cellular
cell membrane
both, a semipermeable layer that allows some substances into the cell and blocks other from entering
Vacuole
both, store water and waste and food being digestion
What cell process is controlled by the nucleus?
cell function and protein synthesis
both chloroplasts and mitochondria are like in that they both have ______ membrane and their own _____
double, DNA