Biology: Cell Structure and Function

Cell theory

States that: all organisms/living things are made of cells, all cells are produced by other living cells, the cell is the most basic unit of life, and energy can flow inside the cell.

Cytoplasm

Jellylike substance inside cells that contains molecules and in some cells organelles. Cytosol- the fluid portion.

Organelle

Membrane-bound structure that is specialized to perform a distinct process within a cell.

Prokaryotic cell

cell that does not have a nucleus or other membrane-bound organelles.

eukaryotic cell

Cell that has a nucleus and other membrane-bound organelles.

Cytoskeleton

network of proteins, such as microtubules and microfilaments, inside a eukaryotic cell that supports and shapes the cell.

Nucleus

organelle composed of a double membrane that acts as the storehouse for most of a cell's DNA. It also direct protein synthesis.

Nuclear Envelope

a double-membrane barrier in eukaryotic cells separating the cytoplasm from the nucleus, protecting DNA and controlling molecular transport. Outer and Inner. is punctuated with pores that control the passage of ions, molecules, and RNA between the nucleoplasm and cytoplasm.

Outer Nuclear Envelope

Faces the cytoplasm, often coated with ribosomes and continuous with the rough endoplasmic reticulum. ribosomes. A lot. Take DNA then make the structure of mRNA.

Inner Nuclear Envelope

Faces the interior (nucleoplasm), contains proteins that connect to the nuclear lamina.

What is protein synthesis?

is the process that cells use to create proteins.

The Nucleolus

Inside the nucleus. It assembles ribosomal subunits that are transported out through the pores of the nuclear envelope to cytoplasm.

Chromosomes

are structures within the nucleus that are made up of DNA. They are only distinguishable from one another when the cell is getting ready to divide.

Chromatin

describes the materials that make chromosomes both when condensed and decondensed.

Mitochondria

responsible for making adenosine triphosphate (ATP) which represents the short-term stored energy of the cell. bean-shaped organelle that supplies energy to the cell and has its own ribosomes and DNA. It’s inside the nucleus.

Peroxisomes

carry out oxidation reactions that break down fatty acids and amino acids. detoxifies many poisons that may enter the body. When oxidation reaction happens it releases hydrogen peroxide - that is damaging to the cells but when it’ confined in the peroxisomes enzymes safely break down h2o2 into oxygen and water.

Endo(“within”)membrane System of the Cell

group of membranes and organelles that works together to modify, package, and transport lipids and proteins.

What organelles belong to the endomembrane system of the cell?

Endoplasmic Reticulum, Golgi Appratus, Lysosomes, Vesicles and Nuclear Envelope.

Endoplasmic reticulum

interconnected network of thin, folded membranes that produce, process, and distribute proteins. (Highway system)

Ribosome

organelle that links amino acids together to form proteins.

Golgi apparatus

stack of flat, membrane-enclosed spaces containing enzymes that process, sort, and deliver proteins. (Post office)

Vesicle

small organelle that contains and transports materials within the cytoplasm.

Vacuole

organelle that is used to store materials, such as water, food, or enzymes, that are needed by the cell.

Lysosome

organelle that contains enzymes to break down debris and old organelles

Centriole

small cylinder-shaped organelle made of protein tubes arranged in a circle; aids cell division (Found only in animal cells)

Cell wall

rigid structure made of cellulose that gives protection, support, and shape to cells in plants

Chloroplast

organelle composed of numerous membranes that are used to convert solar energy into chemical energy through photosynthesis; contains chlorophyll.

Cell membrane

double-layer of phospholipids that forms a boundary between a cell and the surrounding environment and controls the passage of materials into and out of a cell.

What is cellular respiration?

is the process of making ATP through chemical energery found in glucose and other nutrients. In mitochondria, it uses oxygen and produce carbon dioxide as waste product. Oval-shaped double membrane.

Cells need to turn food, usually sugar, into energy, what organelle would you expect to be VERY plentiful in these cells?

Mitochondria

Chlorophyll, in plant cells, is stored in an organelle that is VERY plentiful in leaf cells. What are these organelles?

Chloroplast

What cells, other than plant cells, contain chlorophyll?

Prokaryotes and Protist

What organelle in plants is designed to store water and nutrients?

Vacuole

In a cell, once this organelle locates an invader, they engulf it. What organelle is this?

Lysosome

What organelles would you expect to be plentiful in protein rich muscle cells?

Ribosomes

To what organelle are these protein making organelles often found attached?

Rough ER

Mammalian cells do not have a control center. What organelle is missing from there cells?

Nucleus