Chapter 4 and 5 Flashcards
(69 cards)
1
Q
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
2
Q
Cell theory
A
- Cells are the basic unit of structure + function
- All organisms are made of 1 or more cells
- All cells come from other cells
3
Q
Cell wall
A
polysaccharides, ridgid protective layer
4
Q
Centrosome
A
makes microtubules, made out of centrioles
5
Q
Chloroplast
A
photosynthesis, only in plants
6
Q
Chromatin
A
DNA not in the form of a chromosome, found in the nucleus
7
Q
Chromosome
A
a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
8
Q
Cytosol
A
Fluid portion of cytoplasm
9
Q
Endomembrane system
A
protein pathway, nucleus, ERs, golgi apparatus, vesicles
10
Q
Endoplasmic Reticulum
A
Rough: makes protein
Smooth: controls calcium release, makes hormones, breaks lipids
11
Q
Eukaryotic Cell
A
cell that has a nucleus and other membrane-bound organelles
12
Q
Golgi apparatus
A
stack of membranes in the cell that modifies, sorts, and packages proteins from the ER
13
Q
Intermediate filaments
A
Threadlike proteins in the cell’s cytoskeleton that are roughly twice as thick as microfilaments
14
Q
Lysosome
A
An organelle containing digestive enzymes
15
Q
Microfilaments
A
Fine, threadlike proteins found in the cell’s cytoskeleton
16
Q
Microtubule
A
A hollow rod composed of tubulin proteins that makes up part of the cytoskeleton in all eukaryotic cells
17
Q
mitochondrion (plural, mitochondria)
A
powerhouse, makes ATP (energy)
18
Q
nuclear envelope
A
layer of two membranes that surrounds the nucleus of a cell
19
Q
Nucleolus
A
Found inside the nucleus and produces ribosomes
20
Q
nucleus (plural, nuclei)
A
organelle inside eukaryotic cells that contains most of the cell’s DNA and acts as the control center of the cell
21
Q
Organelle
A
A tiny cell structure that carries out a specific function within the cell
22
Q
Peroxisome
A
breaks down toxic hydrogen peroxide
23
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Plasma membrane
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A selectively-permeable phospholipid bilayer forming the boundary of the cells
24
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Prokaryotic Cell
A
cell that does not have a nucleus or other membrane-bound organelles.
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Ribosome
Makes protein
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Rough ER
ER with ribosomes that makes proteins
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Smooth ER
ER that has no ribosomes, controls calcium release, makes hormones, and breaks lipids
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Transport vesicle
a small membranous sac in a eukaryotic cell's cytoplasm carrying molecules produced by the cell
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Vacuole
Cell organelle that stores materials such as water, salts, proteins, and carbohydrates
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Vesicle
A membrane bound sac that contains materials involved in transport of the cell.
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Active transport
transport that requires energy, low --> high concentration
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Concentration gradient
A difference in the concentration of a substance across a distance.
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Diffusion
Movement of molecules from an area of higher concentration to an area of lower concentration.
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Exocytosis
movement out of the cell using vesicles, active transport
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facilitated diffusion
molecules move through the membrane with the help of carrier proteins (sugar)
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fluid mosaic model
membrane is a mosaic of phospholipids, proteins, steroids (cholesterol)
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hypertonic
higher concentration outside of the cell, water moves out of the cell
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hypotonic
lower concentration outside of the cell, water moves into the cell
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isotonic
equal concentration, water circulates but no net changes
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osmosis
diffusion of water through cell membrane, high to low concentration, aquaporins help water through membrane
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Passive transport
does not use any energy to move, random + automatic
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Phagocytosis + pino cytosis
types of endocytosis (movement into the cell using vesicles) phag- to eat, pino- to drink
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receptor-mediated endocytosis
Molecules attach to receptor proteins on surface, receptor molecules for ma pit, pit pinches off and forms a vesicle with the molecules and receptors inside
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Selective permeability
condition or quality of allowing some, but not all, materials to cross a barrier or membrane
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tonicity
the ability of a surrounding solution to cause a cell to gain or lose water
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kinetic energy
energy due to motion
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potential energy
stored energy
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Metabolism
All of the chemical reactions that occur within an organism
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Central vacuole
plant cell; stores nutrients + waste, increases cell size, acts like lysosome, water collection, turgor pressure
50
Explain why there are upper and lower limits to cell size.
The need to be able to pass nutrients and gases into and out of the cell sets a limit on how big cells can be
51
Describe the structure of a plasma membrane and relate these parts to the
functions of the plasma membrane.
Plasma Membrane - Forms a thin flexible boundary between living cells and it's surroundings. It is made from a phospholipid bi-layer, hydrophobic tails, hydrophilic heads. Diverse proteins are embedded into the membrane.
52
Distinguish between the structures of prokaryotic and eukaryotic cells.
Prokaryotic Cells - Are smaller and simpler, have no nucleus or membrane bound organelles. Instead it has a region called the nucleoid. Has cytosol which is a jelly like substance inside the cell. The inside of the cell is called cytoplasm. Prokaryotes carry chromosomes that carry the DNA and ribosomes, which are tiny structures that make protein from DNA instruction.
Eukaryotic Cells - Larger and more complex cells. Have a membrane bound nucleus as well as membrane bound organelles. Also has cytosol and the inside is called cytoplasm as well, but does not include the nucleus. Has ribosomes as well.
53
Explain why compartmentalization is important in eukaryotic cells
Describe the structures and functions of the four compartments of eukaryotic cells.
-Cell's compartmentalization different localized environments so that multiple incompatible functions can go on inside the cell at the same time
Four Basic Function Groups
1) Nucleus and Ribosomes are like command center that carries out genetic control of the cell
2) Organelles involved in manufacture, distribution, and break down of molecules include: Endoplasmic Reticulum (ER), Golgi apparatus, lysosomes, vacuoles, peroxisomes
3) Energy Processing: mitochondria and chloroplast (Plant's only)
4) Structural support, movement, and communication: cytoskeleton, plasma membrane, and plant cell wall
54
Compare the structures of plant and animal cells. Note the function of each
cell part.
- Plant cells: Rigid cell wall, plasmodesmata, chloroplasts (where photosynthesis occurs), a central vacuole
- Common to both: Nucleus, rough endoplasmic reticulum, cytoskeleton, cytoplasm
55
Describe the structure and functions of the nucleus and nucleolus.
The nucleolus is where the ribosomal RNA is created with the instructions from the DNA. It is a structure inside of the nucleus.Describe the structure and functions of the nucleus and nucleolus.
56
Describe the functions of ribosomes.
The function of the Ribosome is to create polypeptides for excretion or use in the cell.
57
Describe the structures and functions of the components of the endomem-
brane system, including smooth and rough endoplasmic reticulum, Golgi
apparatus, lysosomes, vacuoles, and peroxisomes.
Endoplasmic Reticulum
~It divides the cell into functional departments.
~Smooth ER - synthesizes lipids and processes toxins.
~Rough ER - Takes instructions from mRNA to produces membrane, ribosomes on its surface make membrane and secretory proteins.
Golgi Apparatus
~Flattened stacks act as a sorting department for products of the ER. Also, it ships ribosomes to other organelles and cells surface.
Lysosomes
~Membrane enclosed sac of digestive enzymes that also breaks down damaged organelles. It provides an acidic environment for enzymes and safely keeps them separate from rest of cell.
Vacuoles
~Large vesicles with many functions like contracting. Plant cells contain a large central vacuole that stores molecules, wastes, and facilitates growth.
Peroxisomes
~Metabolic compartments that do not originate from the endomembrane system, how they interact with other organelles is unknown. What is known is some peroxisomes break down fatty acids for fuel, and peroxisomes in liver cells detoxify harmful compounds.
58
Compare the structures and functions of chloroplasts and mitochondria.
. Mitochondria generates energy for the cell in the form of ATP using oxygen and nutrients. Chloroplast is the site for photosynthesis in a plant cell.
59
Compare the structures and functions of microfilaments, intermediate filaments,
and microtubule
Microfilaments thicken the cortex around the inner edge of a cell; like rubber bands, they resist tension. Microtubules are found in the interior of the cell where they maintain cell shape by resisting compressive forces. Intermediate filaments are found throughout the cell and hold organelles in place.
60
Describe the structure and diverse functions of cell membranes.
The cell membrane regulates the transport of materials entering and exiting the cell
61
Relate the structure of phospholipid molecules to the structure and properties of
cell membranes.
Phospholipids are able to form cell membranes because the phosphate group head is hydrophilic (water-loving) while the fatty acid tails are hydrophobic
62
Define diffusion and describe the process of passive transport.
-Diffusion: when particles spread out evenly in space
-Passive transport: diffusion across a cell membrane doesn't require energy
63
Explain how osmosis can be defined as the diffusion of water across a
membrane.
Diffusion is the tendency of molecules to spread into an available space. Passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes.
64
Distinguish between hypertonic, hypotonic, and isotonic solutions.
Hypotonic has a lower concentration of fluid, sugars and salt than blood. Hypertonic has a higher concentration of fluid, sugars and salt than blood. Isotonic has similar concentration of fluid, sugars and salt to blood.A
65
Explain how animal and plant cells change when placed into hypertonic or
hypotonic solutions.
If animal and plant cells are kept in a hypotonic solution then endosmosis will occur.
66
Explain how transport proteins facilitate diffusion.
where a transport protein simply creates an opening for a substance to diffuse down its concentration gradient; and “active transport,”
67
Compare the processes of active transport and facilitated diffusion.
Facilitated diffusion occurs along a concentration gradient from high concentration to low concentration and does not require energy, while active transport from low concentration to high concentration occurs against the concentration gradient and requires energy.
68
Distinguish between exocytosis, endocytosis, phagocytosis, and receptor-
mediated endocytosis.
Image result for Distinguish between exocytosis, endocytosis, phagocytosis, and receptor- mediated endocytosis.
Pinocytosis is non-specific. Phagocytosis targets large structures (e.g., bacteria, food particles…) and is not particularly specific. As its name suggests, receptor-mediated endocytosis is specific for substances recognized by a cell-surface receptor. Exocytosis is typically the secretion of large molecules.
69
Cytoplasm
A jellylike fluid inside the cell in which the organelles are suspended, mostly water
