TEAS 2.1 Cell Structure, Function, and Organization

What is the correct order of biological hierarchy from simplest to most complex?

Chemicals → Cells → Tissues → Organs → Organ Systems → Organism

What are the four major types of macromolecules essential to life?

Carbohydrates, Proteins, Lipids, and Nucleic Acids

What are carbohydrates?

Sugars and starches that the body breaks down into glucose for energy

What are proteins composed of?

Amino acids joined by peptide bonds

What are nucleic acids?

Long molecules made of nucleotides; includes DNA and RNA

What is the fundamental unit of life?

The cell

How many different types of cells are in the human body?

More than 250 different types

What are tissues?

Groups of cells with shared functions that form larger collective groups

What are the four basic types of tissues?

Epithelial tissue, Connective tissue, Nervous tissue, and Muscular tissue

What are organs?

Tissues of different types that join together to carry out a single task

What are organ systems?

Organs that work together to perform coordinated, large-scale functions

What are the three basic parts of every cell?

Nucleus, Plasma membrane, and Cytoplasm

What is the nucleus?

A large organelle within a cell that houses the chromosomes and regulates the activities of the cell

What is the plasma membrane?

A membrane that surrounds the cell and maintains its internal environment through the property of selective permeability

What is cytoplasm?

The material within a eukaryotic cell that supports and suspends structures inside the cell membrane and transfers materials required for cellular processes

What is an organelle?

A specialized part of a cell that has a specific function and is found in the cell's cytoplasm

What is the function of the cell (plasma) membrane?

Maintains the cell's environment through selective permeability; controls what enters and exits the cell

What is the primary function of the nucleus?

Stores genetic information (DNA) and regulates cell activity

What does the nucleolus do?

Assembles RNA and proteins into ribosomes

What is the mitochondrion?

The site of energy production in a cell; generates chemical energy in the form of ATP molecules

Why is the mitochondrion called the "powerhouse of the cell"?

Because it generates ATP, which is the cell's main energy source

Why do skeletal muscle cells have many mitochondria?

Because of the high energy needed for movement

What is the function of ribosomes?

Synthesizes proteins

Where are ribosomes found in the cell?

On the surface of rough endoplasmic reticulum or free-floating in the cytoplasm

What is the rough endoplasmic reticulum (RER)?

A cell organelle containing ribosomes that synthesizes and processes proteins in the cell

Why does the rough endoplasmic reticulum have a bumpy appearance?

Because it contains ribosomes on its surface

What is the smooth endoplasmic reticulum (SER)?

A cell organelle that synthesizes and concentrates lipids in the cell and inactivates toxins and harmful metabolic products

does not contain ribosomes

What is the Golgi apparatus?

A cell organelle that processes and packages proteins and lipid molecules

Why is the Golgi apparatus called the "post office" of the cell?

Because it processes and packages proteins and lipids for distribution

What is a lysosome?

A cell organelle that aids in digestion and recycling of old cell materials; may help destroy invading viruses and bacteria

What enzymes do lysosomes contain?

Digestive enzymes

What is a vacuole?

A cell organelle that serves as storage for a variety of substances, including water, toxins, and carbohydrates

What is a molecule?

An arrangement of two or more atoms bonded together

What is mitosis?

Cell division in eukaryotes that produces two daughter cells, each with the same chromosome number as the parent cell

What is the purpose of mitosis?

Growth and repair; produces two genetically identical daughter cells from one parent cell

What happens during Interphase?

DNA replicates and the cell grows and prepares for division

What happens during Prophase in mitosis?

Chromosomes condense and become visible; nuclear membrane begins to break down

What is a chromosome?

A structure made of protein and one molecule of DNA that contains genetic information

What happens during Metaphase in mitosis?

Chromosomes line up along the cell's equator; spindle fibers attach to chromosomes

What happens during Anaphase in mitosis?

Chromosomes are pulled apart to opposite poles; cell division begins

What happens during Telophase in mitosis?

Two nuclei form and daughter cells separate in cytokinesis

What is cytokinesis?

The physical separation of daughter cells

What is the result of mitosis?

Two diploid daughter cells with identical genetic information

What is meiosis?

Specialized cell division used to create haploid gametes in diploid organisms

What is the purpose of meiosis?

Sexual reproduction; produces four gametes (sex cells) with half the genetic information

What is a gamete?

Sex cell

in males the sperm, in females the eggs (ova)

How many divisions occur in meiosis?

Two divisions: Meiosis I and Meiosis II

What happens during Prophase I?

Homologous chromosomes pair up and crossing over occurs (genetic recombination)

What is crossing over?

Genetic recombination that occurs when homologous chromosomes exchange genetic material during Prophase I

What happens during Metaphase I?

Homologous chromosome pairs line up

What happens during Anaphase I?

One chromosome from each homologous pair moves to each pole; homologous chromosomes separate

What happens during Telophase I?

Nuclear membranes form and the cell separates into two haploid cells; each cell has half the chromosomes (but still as sister chromatids)

What happens during Prophase II?

Daughter cells contain half the chromosomes

chromosomes condense

What happens during Metaphase II?

Individual chromosomes align

What happens during Anaphase II?

Sister chromatids separate and move to opposite ends of the cells

What happens during Telophase II?

Nuclear membranes form and two cells separate into four haploid daughter cells, each with single chromatids

What is the result of meiosis?

Four haploid gametes (sex cells) with unique genetic combinations

What is a chromatid?

One of the two duplicates of a chromosome formed during the cell cycle

What are sister chromatids?

Identical copies of a chromosome joined together

What are homologous chromosomes?

Matching pairs of chromosomes

Diploid

Full set of chromosomes (2n)

Haploid?

Half set of chromosomes (n)

How many daughter cells are produced in mitosis?

Two (2)

How many daughter cells are produced in meiosis?

Four (4)

Where does mitosis occur?

Body (somatic) cells

Where does meiosis occur?

Germ cells (reproductive cells)

Does crossing over occur in mitosis?

No

Does crossing over occur in meiosis?

Yes, during Prophase I

Are the daughter cells in mitosis genetically identical or unique?

Identical to the parent cell

Are the daughter cells in meiosis genetically identical or unique?

Genetically unique

What type of cells are produced by mitosis?

Diploid cells with a full set of chromosomes

What type of cells are produced by meiosis?

Haploid cells with half the set of chromosomes