A&P 3 lecture slides Flashcards
Define cell theory
Cells are the building blocks of living things and are the smallest living units that perform vital physiological functions
Can all cells divide
Not all cells can divide to make two daughter cells (heart/muscle cells)
How are new cells made
They’re made from the division of existing cells
Through what process do red blood cells deliver oxygen to the cells and take in carbon dioxide waste
Diffusion
What can hemoglobin carry and how much max
Hemoglobin can take in oxygen and carbon dioxide, with a maximum of 4 in total
What are the two types of cells
Somatic cells (soma = body) and Sex cells
What are somatic cells
They’re cells that makeup the body structure
How many pairs of chromosomes do somatic cells have
Somatic cells contain 23 pairs of chromosomes
What are sex cells
They’re reproductive cells or gametes
What’s the name of the male sex cells
spermatozoa
What’s the name of the female sex cells
oocytes
How much chromosomes do sex cells contain, are they paired or unpaired.
Each of the sex cells contain 23 unpaired chromosomes
Do the chromosomes in sex cells contain both members of a chromosome pair or only one member
They only contain one member of each pair of chromosomes
What is the medium in which red blood cells flow/move through
Plasma
What is the role of the cell membrane
Separates the internal environment from the external environment
Regulates exchange between intra and extra cellular environments
controls the entry of ions and nutrients
Helps maintain the shape of cells; helps attach cells together and to underlying tissues
How much of the cell membrane is carbohydrates
3%
What molecules does the Glycocalyx layer contain
Proteoglycans
Glycoproteins
Glycolipids
What is the role of the Glycocalyx layer
○ Lubrification/protection
○ Anchoring/locomotion
○ Binding Specificity
○ Recognition
How much of the cell membrane is lipids
42%
What Lipid molecules in the cell membrane
Phospholipid molecules in the membrane’s “phospholipid bilayer”
Cholesterol lipid molecules
What is the Cytoplasm
the material (fluid and structures) between the cell membrane and the nucleus
It is the intracellular fluid that contains ions, nutrients, insoluble proteins, waste products etc.
Cytosol
These are structures suspended in the cytosol that perform specific functions
Organelles
What are the 2 main classes of cell organelles and the difference between the two
○ Non-membranous organelles – do not have membrane surrounding them
Ex: cytoskeleton, microvilli, centrioles, cilia, ribosomes, proteasomes
○ Membranous organelles – possess a complete membrane surrounding them
Ex: endoplasmic reticulum, mitochondria, Golgi apparatus, lysosomes, peroxisomes
What is the Cytoskeleton
Organizes other constituents of the cell, maintains the cell’s shape, and is responsible for the locomotion of the cell itself and the movement of the various organelles within it.
Cytoskeleton microfilaments function
smallest, actin, help determine shape of cell & consistency of cytoplasm, and give structure to microvilli
Cytoskeleton Intermediate filaments function
larger, help maintain shape of cell, hold Organelles in place
Cytoskeleton Microtubules function
largest, primary part of cytoskeleton, help cellular movement, form Spindle Apparatus that distributes chromosomes, and help cilia to move
Define Centrosome
a cellular structure involved in the process of cell division
all cells capable of cell division contain a
Centrosome
Where is the centrosome located and what does it contain
the centrosome is located next to the nucleus and contains a pair of centrioles
Centrioles are composed of short
Microtubules
Centrioles function
Help form the spindle apparatus which helps to distribute chromosomes to the daughter cells during cell division
What are Cilia
long slender extensions of the cell membrane
Where are Cilia mostly located
cells line the respiratory tract, reproductive tract and other areas
What do the Cilia do
beat rhythmically to move fluids or secretions along the inside of tracts, the microtubules inside each cilia causes it to move
Ribosomes function
protein synthesis
What do Ribosomes contain
composed of large and small ribosomal subunits, contain ribosomal RNA (rRNA)
Two types of ribosomes and where they can be found in the cell
Free ribosomes- found floating freely within cytoplasm
Fixed Ribosomes- attached to organelles called rough endoplasmic reticula
What is the two step process in Protein synthesis
Step 1: Transcription occurs within the cell’s nucleus. Assembly of mRNA based on the sequence of DNA bases
Step 2: Translation occurs outside the nucleus at the ribosomes attaching long chains of amino acids together according to the sequence of bases in the mRNA code
What do Proteasomes contain
contain protein-digesting enzymes, called proteases
What are proteins tagged with to indicate they should be broken down
ubiquitin, a molecular label
The Endoplasmic Reticulum is involved in
in the synthesis, storage, transportation, and detoxification of molecules
What are the two parts of the Endoplasmic Reticulum and do they carry out the same function
Rough Endoplasmic Reticulum (RER) has ribosomes on surface and Smooth Endoplasmic Reticulum (SER) no ribosomes
They do not carry out the same functions
Rough Endoplasmic Reticulum (RER) function
it modifies, packages and transports proteins
(workshops for building, modifying and shipping proteins)
Smooth Endoplasmic Reticulum (SER) function
involved in lipid & carbohydrates synthesis and transport
(function as a lipid & carbohydrate factory)
Golgi Apparatus three main functions are
1) packages digestive enzymes into vesicles called lysosomes
2) modifies and packages secretions, hormones and enzymes for release from cell (i.e. exocytosis)
3) renews or modifies the cell membrane
What are Lysosomes
are vesicles produced by the Golgi apparatus and filled with the digestive enzyme lysozyme enzymes
What are the three main functions of Lysosomes
- lysosomes contain a digestive enzyme called lysozyme that breaks down organic molecules or old and damaged organelles
- lysosomes can attack invading bacteria or other pathogens as part of the body’s defense mechanisms
- lysosomes help in the process of autolysis, the total destruction, of injured or dead cells (cell death)
Where are Peroxisomes located
in the cytoplasm(especially liver and kidney cells). Large numbers of peroxisomes are found in the liver cells (hepatocytes)
What are Peroxisomes function
Similar to lysosomes; contain different enzymes
Neutralize free radicals(damaging oxygen ions)
Detoxify alcohol and other drugs
Produce h2O2 (hydrogen peroxide)
What does the Mitochondria do
These organelles, produce energy by the process of aerobic respiration
What happens in the process of aerobic respiration
The compound ADP is transformed into ATP, which is now an energy carrying compound. This energy is transported out of the mitochondria to be used in the cytoplasm and by organelles to carry out their functions
What are the three phases of cellular respiration, the way our cells produce energy. Where the last two phases take place, what do they require and what are they known as.
1) Glycolysis - breaks down glucose into Pyruvic acid takes place in the cytoplasm
2) TCA (Citric Acid) Cycle (where CO2 waste is formed)
3) Electron Transport Chain
The last two of these phases occurs in the mitochondria and require molecular oxygen, and are known as aerobic phases
What are ATP bonds made of and known as? What happens when ATP bonds are broken and what do they turn into when broken?
Adenine and three phosphates are ATP(adenosine tri phosphate), the bonds are high energy bonds.
When the bond is broken energy is released and it turns into ADP if one phosphate bond is broken
What is the Nucleus of the cell
The control center for cellular operations
What are the features of the Nucleus
It has a double layer membrane that surrounds the nucleus, nuclear envelope
What are the contents of the Nucleus
Nucleoli: nuclear organelles that synthesize ribosomes Nucleoli are made of proteins and RNA
Chromatin: loosely coiled DNA strands
What happens when a cell is about to undergo cell division and what happens when it’s not undergoing cell division?
the chromatin becomes tightly coiled into discrete structures called chromosomes
When it isn’t getting ready to divide they are loosely bound and called chromatin
What is Permeability
property determining which substances can and cannot get through a cell membrane
Define Freely permeable, Impermeable and Selectively permeable? Which one do cells fall under
Freely permeable: a membrane letting any substance pass though it
Impermeable: a membrane that does NOT let any substance pass through it
Selectively permeable: letting some substances through but not others
Cells are selectively permeable: letting some substances through but not others
What are the factors that determine what can and cannot go through the membrane?
Molecular size, electrical charge, molecular shape, are substances lipid solubility or water soluble
What is diffusion
Movement of a substance from high concentration to low concentration. Continues until concentration gradient is gone and is a passive process
What is osmosis
the special diffusion of water
Diffusion of water across a semi-permeable membrane in response to differences in solute concentration; from low solute concentration to areas of high solute concentration
What is osmotic pressure
force by which water moves into a solution
What is hydrostatic pressure
The force which acts to oppose osmosis
What is carrier mediated transport
When integral proteins carry ions or organic substrates across the cell membrane
What are the two types of carrier mediated transport
Facilitated diffusion/Passive transport: no energy is used
Active transport: energy is used (ATP)
What is Facilitated Diffusion and when does it happen
The process by which glucose, amino acids, and other large and nonlipid soluble substances enter a cell. No energy is used, a carrier protein carries the substances across the membrane
Only happens if there is greater concentration outside when compared to inside and it must be the right shape/size
What is Active Transport
Molecules or ions are transported into or out of the cell using energy. They can be pumped across the cell membrane against the concentration gradient
○ most popular active transport is the sodium-potassium exchange pump (enzyme)
What is Secondary Active Transport
The movement of one substance into the cell is helped by another substance. For example, glucose is brought into the cell but Na+ needs to be present. Afterwards, Na+ needs to be removed from the cell by active transport which requires the use of ATP.
What is Vesicular Transport and what are the two types
Materials move across the membrane by means of vesicles, small membranous sacs.
There are two types, and both require energy in the form of ATP
1. Exocytosis - movement out of cell
2. Endocytosis - movement into cell
What are the two types of Endocytosis
Pinocytosis (taking in fluids)
Phagocytosis (taking in solids)
most cells do pinocytosis
only specialized cells do phagocytosis
What does the process of Cell division involve
The process involves DNA replication, the duplication of the cell’s genetic material, so that each daughter cell has a full complement of the genomic blueprint
It also involves the division of the nucleus, called mitosis
Many of the body’s cells can produce two daughter cells by the process of cell division but not all can
What are the steps of DNA replication
- the original double stranded helix DNA unzips
- new complementary strands of DNA are built based on the original strands
- an enzyme, DNA polymerase, assembles the new DNA strands by linking nucleotides together
- DNA replication produces a duplicated chromosome
- The duplicated chromosome has two sister chromatids, which are exact duplicates of each other
What is mitosis and what are it’s four phases
Mitosis is the phase of the Cell Life Cycle when the nucleus divides
Mitosis has four phases in this sequence:
▪ Prophase
▪ Metaphase
▪ Anaphase
▪ Telophase
What happens in Prophase
The spindle apparatus forms between two pairs of centrioles
▪ sister chromatids, clearly visible under microscope
▪ the sister chromatids are joined at the centromere
▪ the centromere of each duplicated chromosome is attached to a spindle fiber
What happens in Metaphase
chromosomes move to central zone, the metaphase plate
What happens in Anaphase
sister chromatids split into daughter chromosomes and are pulled to opposite ends of the cell
What happens in Telophase
cleavage furrow develops and process of cytokinesis occurs(splitting of cell into two daughter cells). Cell prepares to return to interphase state
Potassium is higher or lower inside the cell
Higher
Sodium is higher or lower inside the cell
Lower
