Biology quiz #3 Cell structure and function

Prokaryotic cell

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

Plasma (cell) membrane

A flexible boundary that controls the movement of substances into and out of the cell. Gives the cell shape and holds the cytoplasm. The thin layer of protein and fat (phospholipids) that surrounds the cell. It is semi-permeable, allowing some substances to pass into the cell and blocking others.

Cytoskeleton

A network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement. Contains intermediate filaments, microfilaments, and microtubules.

Organelle

A tiny cell structure that carries out a specific function within the cell

Endoplasmic Reticulum (ER)

An interconnected network of thin folded membranes that are responsible for protein and lipid synthesis.

Cell

Basic unit of life

Mitochondria

Cell organelle that converts the chemical energy stored in food into compounds that are more convenient for the cell to use. Spherical to rod-shaped organelles with a double membrane. The inner membrane is infolded many times, forming a series of projections (called cristae). It is known as the "Powerhouse" of the cell; it converts the energy stored in glucose into ATP (adenosine triphosphate) for the cell.

Lysosomes (cell vesicles)

Cell organelles filled with enzymes needed to breakdown certain materials in the cell. This is the digestive system of the cell; this is where the digestion of the cell nutrients takes place. "Breakdown Bodies"

function of endoplasmic reticulum

Cellular function, and creates proteins.

Function of mitochondria

Cellular respiration, makes ATP, powerhouse of the cell.

Function of cytoplasm

Chemical reactions take place and support organelles in place.

Eukaryotic cells

Contains a nucleus and other organelles that are bound by membranes.

Function of chloroplast

Contains chlorophyll which absorbs light energy for photosynthesis.

Function of lysosomes

Digest/break down food, waste, and broken parts.

Vacuoles

Fluid-filled sacs that store materials such as water, salts, proteins, and carbohydrates. They are fluid-filled membrane-surrounded cavities inside a cell; they fill with food being digested and waste material that is on its way out of the cell.

Function of microfilaments

Keep organelles within a cell in place, help with cell division, help cell movement.

Microtubules

Long hollow tubes that help maintain the shape of the cell. They are also important in cell division. They form cilia and flagella.

Function of Golgi apparatus

Modify, sorts and packages proteins and other materials from the ER for storage in the cell or secretion outside the cell

Function of cilia and flagella

Move the cell through fluid or move fluid past the cell.

Centrioles

One of two tiny structures located in the cytoplasm of animal cells near the nuclear envelope; they help to organize cell division.

Chloroplast

Organelles composed of numerous membranes that are used to convert solar energy into chemical energy (ATP); they contain chlorophyll.

Ribosomes

Organelles that link amino acids together to form proteins. Small particles in the cell on which proteins are assembled; made of RNA and protein. Site of protein synthesis.

Function of centrioles

Organize cell division

Cilia and flagella

Projections / Microtubules that are on the outside of the cell and help the cell to move or aid in feeding. Cilia are also used to sweep substances along surfaces.

Function of cytoskeleton

Provides an important structural framework for cell shape.

Function of plasma (cell) membrane

Regulates what enters and leaves the cell, provides a fixed environment for inside the cell, provides protection for the cell.

Function of nucelus

Repository of genetic information, cells control centre

Cell wall

Rigid structure that gives protection, support, and shape to cells in plants, algae, fungi, and bacteria.

Function of microtubules

Shaping the cell, guiding movement of organelles, separating chromosomes during cell division

Function of ribosomes

Site of protein synthesis.

Function of vacuoles

Storage of food, water, waste, salts, and pigments

Function of cell wall

Strengthens and protects the cell.

Cytoplasm

The region between the cell membrane and the nucleus that makes up most of the cell. This is the jelly-like material inside of the cell in which the organelles are located. The cytoplasm surrounds the cell nucleus.

Nucleus

The storehouse for most of the genetic information, or DNA, in your cells; it controls the activities of the cell (by controlling protein synthesis). It contains the cell's genetic material (DNA) and many organelles, including the nucleolus. It is surrounded by the nuclear envelope or nuclear membrane.

Golgi body or Golgi apparatus

This is a flattened, layered, sac-like organelle that looks like a stack of pancakes! It is located near the nucleus and produces the membranes that surround the lysosomes. It modifies, stores, and packages proteins and carbohydrates into membrane-bound vesicles for "export" from the cell. It is the "Talabat" for the cell!

Microfilaments

Threadlike structures made of protein called actin; they form a tough framework that supports some cells. They help muscles to contract and relax.