Gen Bio test 2

What makes DNA cells different from one another?

How much DNA a cell has, and the location of DNA inside the cell

What are the 3 things DNA needs

a pentose sugar, a base, and a phosphate group

What is Domain?

the organization for organisms and it's the largest classification group

Are archaea cells or bacteria cells more abundant

bacteria

What are the differences in prokaryotic and eukaryotic cells

Does it contain a nucleus, the size, and does it have other membrane-enclosed organelles

What is a cell

the building block for all living organisms

What are the three components of cell theory

1) All living organisms are composed of cells. 2. cells are the smallest living thing. 3. cells can only come from pre-existing cells

What are the aspects of a prokaryotic cell

single celled, doesn't contain a nucleus, doesn't contain other membrane-enclosed organelles

What are the two common types of prokaryotic cells?

bacteria and archaea

What are the aspects of a eukaryotic cell?

has a nucleus, largest type of cell, and can contain other membrane-enclosed organelles

What are the four main types of eukaryotic cells?

plants, animals, fungi, and protists

What are the 4 things in a basic cell structure

plasma membrane, cytoplasm, DNA, and ribosomes

What is DNA

The cell's genetic material located inside the nucleus/nucleoid

What does prokaryote DNA look like

single, circular, and double stranded

What does eukaryote DNA look like

multiple, linear, and double stranded

What is ribosome?

responsible for synthesizing proteins, made up of RNA and proteins(made of large and small subunits)

What is bacteria?

One-celled living organisms that they can only with a microscope; very abundant in the environment and our bodies

What is archaea?

prokaryotes that often live in Earth's extreme environments, less abundant than bacteria, and is responsible for the creation of our environment

What is the structure of a prokaryote cell?

Inside: nucleoid(holds DNA), ribosomes, and the cytoplasm

Outside: cell wall(provides support n protection), capsule and pili(helps with attachment), and flagellum(helps with movement)

What is cell structure?

cells differ in size, shape, and numbers; beneficial for cells to be small, as size increases the surface area-to-volume ratio decreases

What can happen if a cell gets too big?

it can either change its shape, divide, or die

What does the cell wall in a prokaryotic cell do?

Protect and support the cell

What does capsule and pili in a prokaryotic cell do?

Helps with attachment

What does the flagellum in a prokaryotic cell do?

Helps with movement

What does a eukaryotic cell have

A membrane-enclosed nucleus, membrane-bounded organelles, has several rod-shaped chromosomes, and is more complex than prokaryotic cells

What consists of a eukaryotic cell?

plasma membrane, cytoplasm, DNA, ribosomes, mitochondria, vesicles & vacuoles, peroxisome, endoplasmic reticulum(ER), and Golgi apparatus

What does the plasma membrane for a eukaryotic cell do?

Separates the cell from it’s surrounding environment and controls the passage of organic molecules, ions, water, and oxygen

What makes the plasma membrane

Phospholipid bilayers embedded w/ proteins

What is the cytoplasm?

A jelly-like substance between plasma membrane and nucelus/nucleoid. Helps determine & maintain cell shape, and aids in cell division

How does the cytoplasm turn DNA into polypeptides?

DNA turns into messenger RNA, which travels to ribosomes that thus creates the primary structure of polypeptides

What is a cytoskeleton?

A network of protein fibers that help maintain the cell’s shape, keeps organelles in place, allows cytoplasm & vesicles to move within the cell, and enables cells to move within multicellular organisms

What are the 3 types of cytoplasm fibers?

Microfilaments, intermediate filaments, and microtubules

What makes a microfilament?

2 intertwined strands of protein which creates the narrowest of the 3 fibers

What does microfilament fibers do?

Used in cellular movement including cell division, and provides some rigidity & shape to the cell

What are intermediate filament fibers made out of

made of several strands of fibrous proteins that are wound together

What is the function of intermediate filament fibers

To provide structure and has a bear tension that maintains the shape by anchoring nucleus and other organelles in place

What are microtubules

Small, hollow, and widest fiber

What are is the function of microtubules?

Helps with cell resistant compressions, provides a track along which vesicles move through the cell, and helps with cell division

Microtubules are the structural element of what 3 things

Flagella, cilia, and centrioles

What are the 2 fibers that aid in cell division

Microfilaments and microtubules

What does a ribosome do?

Synthesizes protein, made of large & small subunits, and receive info for making proteins from the nucleus

What is an endoplasmic reticulum(ER)

Interconnected membranous sacs and tubules that modify proteins and make macromolecules. Attached to the nuclear envelope

What is cisternae

flattened membranes and tubules

What is cisternal space

the hallow portion of tubules

What is the rough ER(RER)

The exterior of the ER that is covered in ribosomes

What does the RER do

Modifies proteins, makes phospholipids for cellular membrans, transfer newly made proteins to the cisternal space(thus going into modifications)

What is the smooth ER(SER)

The other side of an ER that has few/no ribosomes on exterior

What does the SER do

Creates carbohydrates and other lipids, detoxifies cells from medications and poisons, and stores calcium ions

Where can SER and RER go

Either to the inside ER or elsewhere; if elsewhere, macromolecules bud off into transport vesicles to move into the Golgi apparatus

What is a nucleus

Where a cell’s DNA is held, directs synthesis for ribosomes and proteins, assembles ribosome RNA and ribosomal proteins

What does a nuclear pore do

Control the movement of ions, molecules, and RNA between nucleoplasm and cytoplasm

What makes up a nuclear envelope

2 phospholipid bilayers(inner and outer)

What does a nuclear envelope do

Makes up the boundary of a nucleus

What is a nucleoplasm?

The semi-solid fluid inside the nucleus; can find the chromatin and nucleus

What composes the chromatin

Linear structures of DNA composed of protein

What is the chromatin

The chromosomes of the nucleus, every eukaryotic cell has a specific amount

When can you see chromatin

When the cell is getting ready to divide

When is chromatin made

During the growth & maintenance phase when proteins attach to DNA

How are ribosomes made

RRNA(ribosomal RNA) and proteins

What is the mitochondria

The powerhouse of the cell and the site of cellular respiration

What does the mitochondria do

Make ATP using chemical energy in glucose and other nutrients. ATP carries the cell’s main energy

What is the inner mitochondria look like

highly folded to form cristae(folds)

What does the outer mitochondria do

encloses the entire organelle and acts as a protective barrier

What does the peroxisome look like

small, rounded organelles enclosed by single membranes

What does the peroxisome do

Break down fatty and amino acids, and detoxifies many poisons that enter the body

What are vesicles and vacuoles

Membrane-bounded sacs that function in storage and transport

Are vesicles or vacuoles bigger

Vacuoles are slightly bigger but both have the same function

What is the Golgi apparatus

a flattened membrane with cisternae and cisternal space

What is the function of the Golgi apparatus

Accepts transport vesicles from the RER and sorts, packages, and tags macromolecules so they end up in the right space

Molecules are processed and modified in the Golgi

What is the cis face of a Golgi apparatus

Faces the RER and is on the side where transport vesicles are received

What is the secretory vesicle of a Golgi apparatus

Buds from the Golgi to then be exported on the trans

What are the difference between plant and animal cells

Animal cells have centrosome and lysosome

Plant cells have cell wall, chloroplasts, and large central vacuole

What is the cell wall

A rigid covering that protects the cell, provides structural support, and gives shape to the cell

Where is the cell wall located

Outside the plasma membrane and is mostly made of cellulose(polysaccharides made of glucose monomers)

What is a chloroplast

Organelles that carry out photosynthesis, and have their own DNA, ribosomes, and inner/outer membrane

What are the 3 types of chloroplasts

Thylakoids, stroma, and chlorophyll

What is a thylakoid?

A stacked fluid-filled membrane sacs where light harvesting reactions take place; a stack is called a granum

What is a stroma

The fluid enclosed by the inner membrane surrounding the granum

What is a chlorophyll

A green pigment that captures light energy and drives photosynthesis

What does a central vacuole do

Regulates the cell’s concentration of water, takes up most of the cell’s space

What is a centrosome

Microtubule organizing center that is found near the nucleus, are produced and aid in cell division

What is a lysosome

Aids in breaking down proteins, polysaccharides, lipids, nucleic acids, and old organelles

What is the flagella

A long-hair like structure that extends from the plasma membrane and enables an entire cells to move

What is the cilia

Short hair-like substances that move entire cells/substances along the cell’s outer membrane; either contains none or many over the surface

What is cell connection

Cells working together and communicating

What are the two over branch types of cell connection

extracellular matrix and intercellular junctions

What is a extracellular junction

The complex network of proteins and carbohydrates that exists outside of the plasma membrane

What is the function of the extracellular junction

Provides structural and biochemical support to surrounding cells and holds cells together to form tissue, and aids in cell signaling

What are the 2 components of extracellular matrix

Collagen and proteoglycans

What is collagen

protein that provides support and structure

what is a proteoglycans

carbohydrate containing protein molecules that are intertwined with collogenfibers

What is intercellular junctions

direct contact between cells

What are the 4 main types of intercellular junctions

Plants: plasmodesmata

Animals: tight junction, desmosomes, and gap junctions

What is plasmodesmata

microscopic channels that punctuate cell walls

What is the function of plasmodesmata

Creates connections between the cytoplasm of adjacent cells and allows for transport & communication

What is a tight junction

Watertight seals between 2 adjacent cells held together by proteins

What is the function of tight junctions

prevents material from leaking between cells and is mostly found in epithelial tissues

What is desmosome

single contact points that adheres cells together that is composed of cadherins(short proteins) and keratin(intermediate filaments)

What is gap junctions

Channels between adjacent cells, functioning like the plasmodesmata, formed by connexin proteins and is important for cardiac muscles