Unit 2 concept 1-3 notes Flashcards
Unicellular:
Made of a single cell
Multicellular:
Consisting of many cells
Organelle:
specialized structure that performs important cellular functions within a eukaryotic cell
List the 3 principles of cell theory:
- All living things are made of cells
- Cells are the basic unit of life
- All cells come from other cells
Create a Venn diagram comparing prokaryotic and eukaryotic cells.
Prokaryotic: Has cell wall, no nucleus
Eukaryotic: Has nuclues, has membrane beyond organelles
Both: Cytoplasm, Ribosomes.
List the structures that distinguish plant cells from animal cells
The structures that only plant cells have and not animal cells have are that plant cells have chloroplasts, cell walls, and central vacuoles.
Describe the function of the following organelles: cell (plasma) membrane, cytoskeleton, cytoplasm, nucleus, nucleolus, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuole, centrioles (centrosome), cilia, flagella, mitochondria, chloroplast, and cell wall.
Cell membrane: The cell membrane’s job is to control what goes in and out of the cell.
Cytoskeleton: The cytoskeleton gives the cell its shape.
Cytoplasm: The cytoplasm holds everything in place
Nucleus: The nucleus protects the DNA that controls the activities of the cell.
Nucleolus: The nucleolus makes the rRNA which makes up ribosomes.
Rough Endoplasmic Reticulum: The rough endoplasmic reticulum or rough ER makes proteins, packages them for secretion and sends them in the vesicles to the Golgi.
Smooth Endoplasmic Reticulum: The smooth endoplasmic reticulum or smooth ER makes lipids and stores Ca+2.
Golgi Apparatus: The Golgi apparatus gets the vesicles of protein from the ER and transports them around the cell.
Lysosomes: Lysosomes break down dead stuff and can be programmed to self-destruct.
Vacuoles: Vacuoles hold storage like water, nutrients, waste, etc.
Centrioles (Centrosome): Appear during cell division and help cells divide by pulling chromosomes apart.
Cilia an
Defend the claim that ribosomes are the most essential organelle in the cell. In your reasoning include evidence of at least 3 organelles that support the ribosome in accomplishing its function for the cell.
Ribosomes are the most essential organelle in the cell because they are intertwined with 3 other organelles. The smooth and rough ER as well as the cytoplasm. Ribosomes are in the rough ER and they help make proteins. The smooth ER is attached to the rough ER and shares lipids with the rough ER and the ribosomes. Ribosomes are also in the cytoplasm and help it make proteins to use in the cell.
Homeostasis
The need of an organism to stay stable by regulating internal conditions
Solute
What gets dissolved
Solvent
Does the dissolving
Solution
Uniform mixture of two or more substances
Concentration
Amount of solute dissolved in a solvent
Concentration gradient
Difference in concentration of a substance from one location to another
Phagocytosis
cell eating
Pinocytosis
cell drinking
Differentiate between dynamic and state equilibrium with regard to homeostasis.
Dynamic equilibrium is maintained though it doesn’t stay the same it’s within the range while homeostasis stays stable the entire time.
Describe the relationship between a response to stimuli and homeostasis.
A response to stimuli compared to homeostasis is that a stimulus is a change in environment so it has to react to stay in homeostasis but homeostasis is something that stays the same no matter what.
Differentiate between positive and negative feedback loops. Include two examples of each.
In a positive feedback loop the output of the system intensifies the response like childbirth or fruit ripening.
In a negative feedback loop the output of the response causes the system to counter response to return to the set point like the human body temperature or blood sugar regulation.
Explain the role of the cell membrane in maintaining homeostasis on a cellular level. Include which substances can and cannot pass through easily.
The role of the cell membrane in maintaining homeostasis is by controlling what goes in or out of the cell. The substances that can go through the cell are small, nonpolar, hydrophobic, neutral molecules as well as water. What can’t go through the cell are polar and large molecules.
Differentiate between passive and active transport.
Passive transport requires no extra energy because it moves from high concentration to low concentration. Active transport requires extra energy because it moves from low concentration to high concentration.
Describe (either with words or drawings) the six types of transport. List examples of substances transported via each method.
The 6 types of transportation are simple diffusion, facilitated diffusion, osmosis, molecular pumps, exocytosis, and endocytosis.
Simple diffusion: carries O2 and CO2 and small nonpolar molecules
Facilitated diffusion: Carries large molecules like glucose and polar molecule like calcium
Osmosis: Carries water
Molecular pumps: Carries potassium, chlorine, and sodium.
Exocytosis: When nerve cells secrete neurotransmitters to send signals throughout the body.
Endocytosis: When white blood cells engulf bacteria in order to fight infections.
Explain the difference between hypotonic, isotonic, and hypertonic solutions. You may use a picture to help you describe it.
The difference between hypotonic, isotonic, and hypertonic is that hypotonic water is lower the cells cytoplasm while hypertonic water is higher than the cells cytoplasm. Isotonic means its equal inside and outside.
Differentiation
A process that creates special structures and functions
Stem cells
Stem cells: Undifferentiated cells that become differentiated into one or more types of specialized cells
Gastrula
Embryo with 3 differentiated germ layers
Organogenesis
The process of body organ and organ system formation that follows gastrulation.
Cell cycle
A repeated pattern of growth, DNA duplication and cell division that occurs in eukaryotic cells.
Chromosome
One long continuous thread of DNA that consists of thousands of genes and regulatory information.
Gene
A section of DNA that contains the instructions for making a protein.
Sister chromatids
Two identical chromatids.
Centromere
Region of the condensed chromosomes that looks pinched.
Telomere
Ends of the DNA molecule.
Cancer
Uncontrolled cell division.
Metastasize
Spreading of disease from one organ to others.
Carcinogens
Cancer causing agents; chemicals that cause cancer by mutating DNA.
Summarize the order of events from egg and sperm to embryo.
The sperm enters the egg and fertilizes it.
Explain the difference between specialized cells and stem cells.
Specialized cells come in different types like tissues, organs, and organ systems while stem cells can transform into any of them.
List the levels of organization from cell to organism that result from differentiation.
Cell, Tissue, Organ, Organ system, and Organism.
List the two main purposes for cell division.
The two main purposes for cell division are growth and repair.
Sketch and label a homologous chromosome pair before and after S phase. Include a brief description of the importance of S phase.
Because of S phase, at the end of interphase the cells has 2 full set of chromosomes.
Describe all the phases of the cell cycle, including the phases in interphase and mitosis, in order.
The phases of the cell cycle start with the interphase phases.
G1 or gap 1 phase: the cells grow and make proteins.
Synthesis phase: DNA replication occurs by doubling the number of chromosomes.
Gap 2 phase: More cell growth and protein synthesis.
Mitosis: Division of the cell cycle.
Prophase: Chromosomes are condensed and are visible as sister chromatids.
Metaphase: Spindle fibers connect to the centromere of each sister chromatid.
Anaphase: sister chromatids separate pulling away from each other and becoming individual chromosomes.
Telophase: Chromosomes decondense and start to look like chromatin again.
Cytokinesis: Division of cytoplasm into 2 individual cells.
Differentiate between cytokinesis in plants and animal cells.
Cytokinesis in plants forms midway between divided nuclei and gradually develops into a membrane. Cytokinesis in animal cells forms cleavage furrow that pinches the cell into 2 equal parts.
Summarize how cells know when they need to divide. Include examples of the difference between internal and external regulation.
Cells know when they need to divide because each cell divides at a different time based on its needs. If they are in the internal lining of intestines its every 5 days but if it’s like of liver cells its every year. The difference between internal and external regulation is that during internal regulation it sends out signals from inside their nucleus like DNA inside a cell but external regulation sends signals out from outside of the cell like hormones or nutrients.
Explain the key roles of checkpoints and apoptosis in the regulation of the cell cycle.
The key role of checkpoints and apoptosis in the regulation of the cell cycle is that the checkpoints are the critical points where stop and go signal regulate. What the apoptosis does is that it has a programmed cell death and it produces self- destructive enzymes.
Define tumors and differentiate between the two types.
Tumors are clumps of cells that divide uncontrollably. The difference between the two types which are benign and malignant is that benign tumors are clustered and can be harmless and easily removed unlike malignant tumors where they break away and move to other parts of the body making it dangerous and harder to remove.
List several potential causes of cancer.
Some potential causes of cancer are biological factors like your age, skin type and inherited genetic mutations. Your life style like your diet, physical activity, exposure to uv radiation. Viruses and other infections like HPV. Another possible cause is exposure to carcinogens like cancer causing agents, chemicals that cause cancer by mutating your DNA like tobacco smoke, asbestos and many more.
