click below
click below
Normal Size Small Size show me how
Science-Bio Oct 2019
Question | Answer |
---|---|
Define the 3 parts of cell theory | Cells are the basic unit of life, all cells come from pre-existing cells, and all organisms are made up of at least 1 cell |
Cell/Plasma Membrane | The membrane enclosing the cell/outside of the cell |
Cytoplasm | The inside of the cell that absorbs nutrients and stores waste |
Mitochondria | The powerhouse of the cell |
Nucleus | Houses the DNA of the cell |
Endoplasmic Reticulum | Makes protein and transports them |
Golgi Apparatus | An organelle that stores proteins and carries them through the cell |
Vacuoles | A fluid-filled space in plant and animal cells that can hold food and water |
Lysosomes | Destroy energy and recycle it (garbage disposal) |
Centrioles | Control fibres |
Flagella/Flagellum | Propels the cell and brings food towards it |
Cell wall | Keeps water from expanding the cell to a point where it explodes |
Chloroplasts | Carry out photosynthesis |
Central Vacuole | Is a garage disposal for waste, stores water and nutrients |
Which organelles are only in plant cells? | Cytoplasm, Cell wall, chloroplasts |
Which organelles are only in animal cells? | Lysosomes, Centrioles, flagella |
What is a chromosome? | A piece of DNA that can reproduce itself and is part or all of a genome |
What is ATP and how is it made? | It is what cells need to use as energy, they take in sugar and O2 into their mitochondria to generate ATP |
Why do cells go through the cell cycle? | Because they need to duplicate so an organism can grow or maintain itself |
What are the 4 stages of the cell cycle? | G1, (stationary phase), S phase, G2, Mitosis |
G1 | First growth phase: Cell grows, carries out its normal functions and checks its resources and environment to see if it is ready to move into the next phase |
What can happen after G1? | The cell doesn't get the go ahead and goes into stationary phase |
Stationary phase | The cell is no longer dividing- Most of our cells are like this |
(S) Synthesis phase | The DNA is replicated, centriole and chromosomes are also replicated (DNA synthesis) |
What is the centriole? | The centriole controls the movement of the chromosomes during mitosis |
What are the duplicated chromosomes called? | Chromatids |
G2 | Second growth phase: the cell makes sure everything as properly replicated and makes corrections; continues to make organelles for the two eventual cells |
What are the four phases of mitosis? | Prophase, Metaphase, Anaphase, Telaphase |
Mitosis- Prophase | Prophase: DNA is replicated, chromosomes and DNA start to condense, nuclear membrane dissolves, centrioles separate, spindle bodies move to opposite sides of the cell |
Mitosis- Metaphase | Metaphase: The chromatids meet in the centre of the cell and line up with the spindle fibres |
Mitosis- Anaphase | Anaphase: One of each chromatid is pulled towards opposite ends of the cell by microtubules, and once they are almost at their respective sides constriction in the middle of the cell begins |
Mitosis- Telaphase | Telaphase: Membranes begin to reform and constriction continues between the new cells, the cytoplasm is split between the cells during cytokinesis |
What is Cytokinesis? | When the cytoplasm between the two new cells pinches off and is separated and the cell membrane closes and divides the two cells |
What are the 3 types of cell death? | Necrosis, Apoptosis, Autophagy |
What is necrosis? | Unplanned cell death; cell takes in too much water, it explodes, the contents of the cell leak out and damage other cells caused by toxins |
What is Apoptosis? | Planned cell death; cells get internal or external signals to die, membrane and cytoplasm form blebs which break off, the nucleus compacts and then fragments |
What is Autophagy? | Planned cell death; a cell is starving so it makes a special organelle called an autophagosome which fuses with lysosome and eats all other organelles for energy |
What are the 2 ways that apoptosis is used in development? | Organ sculpting, removal of tissues |
How does cancer occur? | Cells misinterpret/ignore external or internal signals and reenter the cell cycle, cells start to grow out of control, a tumour grows |
How does cancer occur pt.2? | A tumour starts from one cell, as it grows and divides it accumulates changes, if it isn't stopped it will invade other tissues and invade the blood stream which can cause metastasis |
What is Metastasis? | When cancer has travelled through the body and begins growing in a separate spot from the main spot of cancer |
What are some cell specializations in plants leaves? | Leaf: cells that photosynthesize, transport cells (they move water and nutrients) |
What are some cell specializations in plants stems? | Stem: Meristem cells, transport cells |
What are some cell specializations in plants roots? | Roots: Root cells- take in water, nutrients, soil, also store sugar |
What are some cell specializations in animals? | Skin cells, fat cells, neurons (send + receive messages), heart, specialized muscles in digestive system, skeletal muscles, osteoblasts and osteoclasts, related connective tissue (tendons, cartilage) |
What are the organs of plants? | Leaves, stems, roots |
What are the 3 types of plant tissues? | Dermal tissue (outer coating), ground tissue (the tissue not deemed vascular or dermal, e.g. the cells that carry out photosynthesis, the structural cells in stems, etc.), vascular tissue (transport) |
What is the Epidermis in stems? | Dermal tissue; it is the outside of the stem which protects the stem from disease, predators, losing water, etc. |
Which parts of the stem are ground tissue? | Pith (centre of stem), Fibre cells (make the stem strong), Cortex (just inside epidermis, protective layer + structural) |
What is Phloem and what separates phloem cells? | Vascular tissue; transports sugars, cells are alive but have lost nuclei; separated by sieve plates |
What are companion cells? | Companion cells are beside Phloem cells, they use channels to provide Phloem cells with the necessities of life |
What is Xylem? | Vascular tissue; transport water and minerals, cells are dead, they are tubular, they have lignin cell that keep them strong |
What is the Epidermal structure on leaves called? | The cuticle, it is on both sides of the leaves |
What are the opening s in the cuticle called? | Stomata, they allow CO2 to enter the leaf, O2 to leave, and water to evaporate |
What is a leaves' ground tissue called? | Mesophyll |
What does Mesophyll do? | Contains the cells that carry out photosynthesis |
Does the root of a plant have an epidermis? | Yes |
What is the ground tissue of a root structure called? | Cortex |
What kind of Vascular tissues does the root structure have? | Xylem to transport water to the rest of the plant and phloem to bring sugars for storage |
Which kinds of plants have fibrous roots? | Grasses (corn, grass, rice, etc.) |
Which kinds of plants have tap roots? | Carrots, most trees, etc. |
What is the function of roots? | Roots draw water from the soil through osmosis to feed the plant, water passes through the cells bringing minerals along with it |
How is water transported from the roots to the leaves? | Water enters the roots through osmosis, it is drawn to an area of lower concentration, the water molecules stick together and move through the plant like a train |
How does water leave the leaves? | Through evaporation |
What is seed germination? | When a seed starts to grow |
How does a bean grow? | The first root (radical) grows from the hypocotyl, root grows like a loop and at the highest point it turns green, it sprouts and the two halves of the bean (the cotyledon) also turn green, they act as leaves until the first leaves emerge |
What do cotyledon do? | The provide the plant with food until the foliage leaves emerge and then they shrivel |
How does corn grow? | 2 projections emerge from the seed; 1 is a radicle (root) and 1 is the coleoptile (shoot), they both grow and when the coleoptile emerges it turns green and sprouts foliage leaves |
Which parts of roots and shoots grow? | The tips; the apical meristem |
What is the apical bud? | The bud at the top of the plant that sends hormones to the (dormant) lateral buds which can suppress their growth |
What happens if you get rid of the apical bud? | The signals to the lateral buds will stop, therefore letting them grow and allowing the plant to branch out |
Do flowers have female and male parts? | Yes |
What are the female parts of the flower? | The female part is called the ovary, they contain ovules |
What are the male parts of the flower? | The male part is called the anther, it produces pollen |
Can some kinds of plants fertilize themselves? | Yes |
Can all plants fertilize themselves? | No |
What else can fertilize plants? | Wind, birds (humming birds), small mammals (bats), insects (bees, butterflies, etc.) |
Where are seeds produced? | In the ovary |
Where is pollen produced from? | The anther |
Are plant diseases specific to the plant type? | Yes |
Are Rembrandt tulips (the disease) deadly? | No, it just causes a colour defect |
How are galls on trees caused and are they deadly? | By (insects, fungi, worms, etc.) that enters the plant and signals to the tree to grow differently (benign tumours), they are not deadly |
What is another word for not deadly/not harmful? | Benign |
Is tomato mosaic virus deadly? | Yes, it destroys the leaves and is very infectious |
Is cornsmut fungus benign? | No, it attacks the seeds and changes how they grow; the attacked seeds don't grow as seeds |
What is the epidermis in animal tissue? | Skin cells- (they have to be connected very tightly to do their job and protect us from water, toxins, etc.) |
What is the oviduct tissue? | Made of epithelial cells, it is rippled to produce extra surface area |
What is fat tissue called? | Adipose tissue |
What is striated muscle? | Skeletal muscle |
What is smooth muscle? | Smooth muscle: It surrounds internal organs, is in blood vessels, it pumps blood through blood vessels; is in digestive system, on the outside of the stomach and intestines to push food through |
What is cardiac muscle? | Muscles that contract together following a pulse |
What does red blood do? | Carry O2 through the body |
Do red blood cells have a nucleus? | No |
What do red blood cells get their colour from? | Hemoglobin- special type of protein that carries O2 |
What do white blood cells do? | The attack bacteria, viruses, germs, etc. and are involved in the immune system |
Do white blood cells have a nucleus? | Yes |
What do neurons do? | They are part of the neural tissue; they transmit electrical + chemical signals that pass on info |
What do neurological cells do? | They act as insulators to see that signals don't get crossed |
What do osteoblasts do? | They build bone |
What do osteoclasts do? | They reshape bone by breaking it down |
Do all cells have the same DNA blueprint? | Yes, but according to the signals they receive they carry out different functions and become new things |
What kind of cells are stem cells before they are specialized? | Multipotent cells; they can become anything |
What do patterning genes do? | They provide cues for how to grow |
What happens if a patterning gene is turned on in the wrong place? | It mutates growth |
How do scientists understand the way patterning genes work? | They can cause mispatterning |
What happens when pharmaceuticals and plastics get into our water system? | They can emit things that look like hormones into the water; this can change how organisms develop; Eg. they can change gender and become sterile, they can get mispatterning cues |
Is an egg a single cell? | Yes |
What happens when an egg divides? | It produces the parts for the body |
What does totipotent mean? | That something can develop into any kind of cell in a certain thing |
Is an egg totipotent? | Yes, it can develop into any kind of cell both in the embryo and in the extraembryonic tissue (eg. placenta) |
Where does the developing embryo come from? | The inner cell mass (the tissues inside the blastocyst) |
What does pluripotent mean? | That these cells can make whole embryo but not the extraembryonics |
What happens as the embryo develops? | As tissues and organs form it becomes more specialized, and eventually they become unipotent- they can only become 1 type of cell |
In adult life, what do stem cells in tissues serve to do? | Make repairs, they are unipotent in adult life so they no longer can become new tissues |
In adult life, what do blood stem cells serve to do? | Make many types of blood cells (immune cells, etc.) |
What does the respiratory system do? | The respiratory system is the lungs; they bring in oxygen which helps to make energy and release carbon dioxide which is a waste product |
What does the urinary system do? | Excretion through the kidneys which balance water and salt levels and get rid of nitrogen waste |
What does the reproductive system do? | Produces eggs and sperm |
What is the integumentary system? | Skin, nails, hair |
What does the skeletal system do? | Support the structure of the body with bones, tendons, and cartilage |
What do skeletal muscles do? | They help us move (we can't move without them) |
What does the muscular system do? | It helps us move and move things through our bodies with skeletal muscles, smooth muscles, and cardiac muscles |
What does the nervous system do? | It controls the body by sending and receiving signals (it is an autonomous system (it controls things that we need to keep running constantly) |
What does the circulatory system do? | It moves and circulates blood, it sends O2 and nutrients around the body and removes waste |
What does the endocrine system do? | It signals the body with hormones |
What does the lymphatic system do? | It moves fluid around the body and is important for immunity |
What does the digestive system do? | It digests our food, absorbs nutrients, and gets rid of waste that we can't digest |
How does the digestive process work? | We take in food through our mouths, a digestive enzyme in our saliva turns starch into sugar, in our stomach our food gets mixed with acids, enzymes start to break it down, the mix gets passed to intestines. |
How does the digestive process work? pt.2 | Once it is passed to intestines there are different enzymes added to the mix by our liver, pancreas, gall bladder, small intestine, etc., the nutrients is absorbed, anything unable to be digested is passed out through our anus |
What are digestive enzymes? | Protiens that digest food |
What is the stomach and what does it do? | The stomach is a bag where food collects, it has folds with glands that produce acid and enzymes, it is surrounded by muscles that contract to mix the food |
True or false: A large part of our feces is bacteria | True |
True or false: A large part of our digestion is done by bacteria? | True |
True or false: There is more bacteria in our gut then in the rest of the human body | True |
What do the liver and gall bladder do? | They produce bile which helps us digest fat |
Is fat a lipid? | Yes |
What does the pancreas do? | It controls acidity, it creates enzymes to digest protein and carbs, it makes hormones to control food absorption |
What is in the excretory system? | Our kidneys and bladder |
What does the excretory system do? | It cleans our blood, rebalances ions and electrons, rebalances water concentration in blood, removes nitrogenous waste-byproduct of digestive proteins |
What organs does the circulatory system contain? | The heart and blood vessals |
True or false: Blood vessels get progressively smaller as you move away from the heart | True |
How does blood circulate through the body? | Blood reaches the heart, the blood is pumped to the longs where CO2 is removed and O2 is added, blood returns to the heart and is then pumped to the rest of the body |
What are the blood vessels that leave the heart? | Arteries |
What are the blood vessels that return to the heart? | Veins |
How do arteries turn into veins? | They pass through capilleries |
How does the respiratory system work for air breathers? | We take in O2 through our moth or nose, it goes into our lungs and inside our lungs, in the alveoli, it exchanges the O2 that comes in for Co2 that leaves |
What do animals that don't breathe air use for the respiratory system? | Gills |
Do animals with gills have alveoli? | No, rather they have filaments in their gills that carry out the same function as alveoli; they take in the O2 from the water and release Co2 |
What is DNA? | Biological molecule that holds the blueprint for life |
True or false: All nucleotides carry different sugar and phosphate | False, all nucleotides carry the same sugar and phosphate |
How many bases can a nucleotide carry? | 4; A,G,C, or T |
In DNA, which nucleotide bases have to pair with each other? | A must pair with T, G must pair with C |
What happens if DNA strands aren't together? | The DNA changes and genetic mutation occurs |
How is AGTC arranged? | In triplets called codons |
True of false: Mismatches in genetic mutation are often caught | True |
At what time are genetic mistakes formed? | During duplication |
True or false: The result of mismatches in genetic mutation always causes problems | False, they often cause problems but not always |
What happens when mutations occur in our cells during our lifetimes? | Cancer can occur |
True or false: All cancer is caused by genetic mutation | True |
What is epithelium? | A type of animal tissue that lines the outer surface of organs and blood vessels around the body |
What is columnar epithelium? | A type of tissue where are cells are formed together in tall, thin, column-like way; usually found lining the organs in the digestive system |