UNIT 2 pt.1 - Cells Structure and Function | AP Biology

Currently only updated to current notes; it will be updated more as time passes.

Compare nucleus of prokaryote and eurkaryote

Prokaryotic cells have no nucleus and Eukaryotic cells have a nucleus with DNA

Where is DNA kept in a prokaryotic cell?

The nucleoid

Compare Organelles of prokaryote and eurokaryote?

Prokaryote has no membrane-bound Organelles, eukaryote has membrane-bound organelles

What type of organisms are prokaryotic?

Bacteria and Archaea

What type of organisms are eukaryotic?

Plants, animals, fungi, protista

What limits the size of Eukaryotes?

Metabolic activities

What are the 4 basic features of all cells?

Plasma membrane (semi-permeable), Cytosol (cytoplasm/Organelles), Chromosomes (genes), Ribosomes (proteins)

What is the structure of a Eurkaryotic membrane?

Membrane divides the cell into compartments, made of phospholipids (heads hydrophilic, tails hydrophobic), double layered, semi-permeable

What are physical properties of the nucleus?

Large, spherical, largest and most obvious organelle. Covered by a nuclear membrane with pores; has a nucleolus inside

What does the nucleus do?

Stores DNA and information

What does the nuclear envelope do?

Barrier b/w nucleus and cyotoplasm, controls selective (semi-permeable) passage of molecules into and out of the nucleus via nuclear pores

What does the nucleolus do?

Synthesizes ribosomal RNA (rRNA)

What are ribosomes made of?

rRNA and proteins

What do ribosomes do?

Uses info from DNA to make proteins (protein factories)

What type of ribosomes are in cytosol?

Free ribosomes

What type of ribosomes are on the outside of the rough endoplasmic reticulum/nuclear envelope?

Bound ribosomes

What does the endoplasmic reticulum do?

Extension of nuclear envelope, a biosynthetic factory split into smooth ER and rough ER, most of the cell mass

What does the smooth ER do?

Synthesizes lipids, metabolizes carbohydrates, stores calcium, detoxifies poison

What does the rough ER do?

Bound ribosomes, makes proteins and membranes

What are the physical flattened, membranous sacs on the golgi apparatus?

Cisternae

What does the golgi apparatus do?

Shipping, modification, and packaging center for products of the ER; sorts materials into transport vesicles and manufactures certain macromolecules

How do the chemical modifications from the golgi apparatus affect proteins?

Mediated by enzymes, determines function, stability, folding, and target location (where they’re going)

What is an example of protein modification from golgi apparatus?

Glycosylation: carb attaches to functional group

What does rRNA do?

Essential to make ribosomes and catalyze protein sythesis

What are lysosomes composed of?

Membranous sac of hydrolytic enzymes (enzymes that break down larger molecules using water)

What are the functions of lysosomes?

Hydrolyze proteins, fats, polysaccharides, and nucleic acids

What is autophagy and what organelle uses it?

Self-devouring of a cell, Lysosome

What are vacuoles composed of?

Membrane -bound sacs w/ varied functions

What do food vacuoles do and how are they made?

Digest and store nutrients, formed by phagocytosis

What is phagocytosis?

Ingestion/eating of bacteria and large particles

Where are contractile vacuoles found and what is their function?

Pumps excess water out of cells, found in freshwater protists

Where are central vacuoles found and what do they do?

Found in plant cells, holds water/organic compounds

What do vesicles do?

Short-term storage or transport of substances like proteins, lipids, and nutrients

What is the mitochondria’s function?

Chemical energy conversion (powerhouse of the cell)

What are cristae?

Folds within Mitochondria’s inner membrane to increase surface area for ATP respiration

What does mitochondrial matrix do?

Kreb’s cycle (breaks down molecules and creates energy), protein folding

What do chloroplasts do?

Capture light energy for photosynthesis

What does chlorophyll (chloroplasts) do?

Makes plant food

What does the structure of chloroplasts include?

Thylakoids (light-dependent reactions), membranous sacs, stroma (fluid matrix, Calvin cycle), and internal fluid

What are plastids?

Small organelles in cytoplasm containing pigment or food with a double membrane

What do plastids do?

Contributes to plant metabolism, promoting growth and development

What are peroxisomes?

Oxidative organelle w/ specialized metabolic compartments bounded by a single membrane

What is the function of peroxisomes?

Undergoes oxidation reactions with detoxify harmful substances (hydrogen peroxide) and converts it to water, also aids in breakdown of lips

What is the cytoskeleton?

Network of fibers extending throughout the cytoplasm

What does the cytoskeleton do?

Organizes cell structures and activities, anchors Organelles, and acts as monorail for vesicles, provides support/shape

What are cytoskeletons composed of?

Microtubules, intermediate filaments, and microfilaments

What is the shape of microtubules?

Hollow tubes

What are the functions of microtubules?

Maintenance of cell shape (compression resisting), cell motility (as in cilia or flagella), chromosome movements in cell division, organelle movements

What is the structure of microfilaments?

Two intertwined strands of actin

What is the function of microfilaments?

Maintenance of cell shape (tension bearing), changes in cell shape, muscle contraction, cytoplasmic streaming, implant cells, cell motility (anoeboid movement), division of animal cells

What is the structure of intermediate filaments?

Cables of fibrous proteins

What is the function of intermediate filaments?

Maintenance of cell shape (tension bearing), anchorage of nucleus and certain other organelles, formation of nuclear lamina (protein network)

What are centrosomes/centrioles?

Primary organizing center

Which cell has a pair of centrioles on the centrosome?

Animal cells

What do the clia and flagella do?

organelles that are hair-like structures that control motion for cells (sheathed by plasma membrane)

What are dyneins?

Motor proteins that drive bending movements of clia and flagella