Bio

What is homeostasis and why is it important?

Homeostasis is the maintenance of a constant internal environment. Automatic control systems throughout the body maintain temperature and water at steady levels, which are required for cells to function properly.

What makes a cell prokaryotic?

prokaryotic cells are primitive cells that lack a nucleus. instead of storing genetic material in well-organized chromosomes protected by a membrane-bound nucleus, their genetic information is in a circular loop called a plasmid, which are little rings of genetic material that are copied along with the normal process of cell division and can also be exchanged between prokaryotes.

3 parts of a nucleotide?

Like DNA, RNA polymers are make up of chains of nucleotides *. These nucleotides have three parts: 1) a five carbon ribose sugar, 2) a phosphate molecule and 3) one of four nitrogenous bases: adenine, guanine, cytosine or uracil.

Eukaryotic?

any organism having as its fundamental structural unit a cell type that contains specialized organelles in the cytoplasm, a membrane-bound nucleus enclosing genetic material organized into chromosomes, and an elaborate system of division by mitosis or meiosis, characteristic of all life forms except bacteria, blue-green algae, and other primitive microorganisms.

Differences/similarities between plant and animal cells

1) Both cells have cell membranes 2) Both cells are eukaryotic 3) Both cells have mitochondria,ribosomes, endoplasmic reticulum, Golgi, and lysosomes. Differences 1) Plant cells have cell walls, animal cells do not. Both cells have cell membranes. 2) Plant cells have chloroplasts (make chlorophyll), animal cells do not. 3) Plant cells have a large central vacuole, while animal cells have many smaller vacuoles throughout the cell 4) Plant cells use the sun's energy and use photosynthesis to convert sunlight into food. Animal cells use energy from consumed food to turn sugar into ATP. 5) Plant cells turn Carbon Dioxide into Energy and release oxygen, while animal cells turn oxygen into energy and release carbon dioxide. 6) Plant cells multiply by Cytokinesis.

The traits shared by all living things?

1. all living things have dna 2. all living things need food and shelter 3. all living things obtain/use energy 4. all living things need to adapt 5. all living things respond to their enviornment 6. all living things adapt 7. all living things reproduce 8. all living things grow and develop

Hypertonic means...?

A hypertonic solution contains a greater concentration of impermeable solutes than the solution on the other side of the membrane. When a cell's cytoplasm is bathed in a hypertonic solution the water will be drawn into the solution and out of the cell by osmosis. If water molecules continue to diffuse out of the cell, it will cause the cell to shrink.

Hypotonic means...?

A hypotonic solution is one in which the amount of solute(dissolved substance) is less than the amount of that solute in the cell. Water will flow from the solution into the cell. A hypertonic solution is one in which the amount of solute is more than the amount of that solute in the cell. A cell in a hypotonic environment gains water and swells.

What is active transport?

A kind of transport wherein ions or molecules move against a concentration gradient, which means movement in the direction opposite that of diffusion - or - movement from an area of lower concentration to an area of higher concentration. Hence, this process will require expenditure of energy, and the assistance of a type of protein called a carrier protein.

Parts of microscope and how it works?

A microscope is an optical instrument that allows you to see objects magnified. Some microscopes are so strong that you can see things that the human eye can't see alone like cells, ash, and snowflakes. A simple microscope is one that uses only one lens to magnify, such as a magnifying glass. A compound microscope uses two or more lenses to magnify the specimen. The microscope you have at school probably uses a combination of lenses to magnify, but for their research some scientists have microscopes that use electronics to magnify. They are called electron microscopes. There are many other types of microscopes including ones that use x-rays, gases, and lasers. Microscopes allow us to see what makes people sick and how organisms work. We can study the make up of rocks, and even fluids. For example, we can see exactly what is in a glass of drinking water.

What is pH scale?

A pH scale is a measure of how acidic or basic a substance is. While the pH scale formally measures the activity of hydrogen ions in a substance or solution, it is typically approximated as the concentration of hydrogen ions.

How do emulsifiers work?

An emulsifier molecule works by having two parts. One part of the molecule has an electric charge (like an ion) and will dissolve in water but not in oil. This part of the molecule (known as the head) is called hydrophilic which means water loving. The other part (called the tail) is a long hydrocarbon which will dissolve in oil but not in water. This part of the molecule is called hydrophobic which means water fearing.

How are mono- and polysaccharides different/similar?

Carbohydrates, which are chemical compounds consisting of carbon, hydrogen and oxygen, are one of the primary sources of energy for organic life. Also known as saccharides, or more commonly as sugars, carbohydrates are often subcategorized by their chemical structure and complexity into three different types: monosaccharides, disaccharides and polysaccharides. Each of these compounds have their own distinct structure and purpose within biochemistry.

How would you know that Canis lupus and Canis domesticus are closely related?

Categories within taxonomic classification are arranged in increasing specificity. The most general category in taxonomic classification is domain, which is the point of origin for all species; all species belong to one of these domains: Bacteria, Archaea, and Eukarya. Within each of the three domains, we find kingdoms, the second category within taxonomic classification, followed by subsequent categories that include phylum, class, order, family, genus, and species. At each classification category, organisms become more similar because they are more closely related. As scientific technology advances, changes to the taxonomic classification of many species must be altered as inaccuracies in classifications are discovered and corrected.

What are the different ways that substances cross the lipid bilayer?

Cell membranes are a barrier to most substances, and this property allows materials to be concentrated inside cells, excluded from cells, or simply separated from the outside environment. This is compartmentalisation is essential for life, as it enables reactions to take place that would otherwise be impossible. Eukaryotic cells can also compartmentalise materials inside organelles. Obviously materials need to be able to enter and leave cells, and there are five main methods by which substances can move across a cell membrane: Lipid Diffusion Osmosis Passive Transport Active Transport Vesicles

Dehydration and hydrolysis -- Define each.

Dehydration synthesis is the removing of the hydroxl(-OH) and the hydrogen atoms from two organic substances which merges them into one(covalent bond). They can be protein(peptide bond), sugars(polysaccharide), whatever. An example of this is when glucose and fructose undergo dehydration and form sucrose. If there were 1000 molecules produced then there would be 999 water molecules accompanying it. There is always n-1 water's produced from the dehydration synthesis. Hydrolysis of the addition of water to break down the one molecule into the two parts. Such as sucrose into fructose and glucose. Same number rules, 1000 molecules of sucrose would require 999 molecules of water.

Different types of endocytosis? How are they different/alike?

Endocytosis consists of phagocytosis, pinocytosis, and receptor-mediated endocytosis. Endocytosis takes particles into the cell that are too large to passively cross the cell membrane. Phagocytosis is the taking in of large food particles, while pinocytosis takes in liquid particles. Receptor-mediated endocytosis uses special receptor proteins to help carry large particles across the cell membrane.

What kind of molecules can they move (endo/exocytosis)?

Endocytosis is an energy-using process by which cells absorb molecules (such as proteins) by engulfing them. It is used by all cells of the body because most substances important to them are large polar molecules that cannot pass through the hydrophobic plasma or cell membrane. The opposite process is exocytosis.

How does endo/exocytosis work?

Endocytosis is the cellular uptake of biological molecules and particulate matter via formation of new vesicles from the plasma membrane. Exocytosis is the cellular secretion of biological molecules by the fusion of vesicles containing them with the plasma membrane. Basically, that means endocytosis takes IN molecules, exocytosis puts OUT molecules.

Do the different types of endocytosis require energy?

Endocytosis: (Endo - means to bring in) Energy requiring process where cell membrane surrounds molecules, forming a pocket which becomes a vacuole in the cytoplasm.

What is facilitated transport?

Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins.

4 types of organic compounds?

For all living organisms, four types of organic compounds are essential: carbohydrates, lipids, proteins, nucleic acids. Phospholipid: a type of lipid in which the macromolecule is composed of two molecules of fatty acids and a phosphate group joined to one molecule of glycerol ➢ Phospolipids make up the cell membrane.

Isomer? Example of one also?

In chemistry, isomers are molecules that share the same chemical formula but differ in the arrangement of atoms. (Isomers in chemistry should not be confused with nuclear isomers, corresponding to atomic nuclei that share the same atomic number and mass number but differ in their energy states.) Often, there are only minor differences in the structures of the molecules, and the isomers therefore exhibit similar properties. In biological systems, certain isomers are more active than others.

Isotonic means...?

Isotonic means that the concentration of solutes is the same outside a cell as inside a cell. That means the water concentration is also the same outside and inside the cell. So the cell is in balance with its environment and won't experience swelling or shrinking due to water entering or leaving the cell. It's the best environment for the cell.

What role do steroids play and what is their basic shared structure?

Lets start by defining the words steroid and hormone. Steroid- is a fat soluble organic compound with an origin from plants or animals; it is characterized by its "steroid nucleus" and is a class of lipid. Hormone- a chemical messenger produced by endocrine glands, whose secretion are liberated directly into the bloodstream and transported to a distant part or parts of the body, where they exert a specific effect for the benefit of the body as a whole. 7 Steroid hormones are composed of three six membered rings and one five membered ring. These organic compounds are easily identified from a visual stand point by their "steroid nucleus", which is called cyclopentanophenanthrene. This nucleus looks like this (show transparency), all hormones have an oxygen at C-3 and a varied substituent at C-17. This substituent varies according to the different kind of steroid hormones at hand and can be either Alpha or Beta depending on where they are situated below the plane of the molecule. There are 6-centers of asymmetry, as a result, there are 64 possible compounds (stereoisomers) with this structure. They are located at C-5, C-10, C-8, C-9, C-14, and C-13. The rings adopt or puckered conformation over the boat form beacause its more stable (steric factor). 2

What are cilia and flagella? What are they made up of?

Microtubules help the cell resist compression, provide a track along which vesicles can move throughout the cell, and are the components of cilia and flagella. Cilia and flagella are hair-like structures that assist with locomotion in some cells, as well as line various structures to trap particles. The structures of cilia and flagella are a "9+2 array," meaning that a ring of nine microtubules is surrounded by two more microtubules. Microtubules attach to replicated chromosomes during cell division and pull them apart to opposite ends of the pole, allowing the cell to divide with a complete set of chromosomes in each daughter cell.

Four nucleotides that make up DNA?

Nucleotides in DNA contain four different nitrogenous bases: Thymine, Cytosine, Adenine, or Guanine. There are two groups of bases: Pyrimidines: Cytosine and Thymine each have a single six-member ring.

Diffusion vs Osmosis? How are they similar and how are they different?

Osmosis and Diffusion are similar because they all have to deal with the movement of particles from an area of higher concentration to an area of lower concentration. The difference is that Diffusion is the movement of Particles and Ions While Osmosis is the movement of Water only. Also They both move from higher concentration to lower because they need to balance out.

What are the multiple functions of proteins?

Proteins often consist of multiple parts, known as domains, that have distinct functions, so a single protein may have multiple functions in the cell. For example, proteins called transcription factors regulate the expression of genes by having a domain which binds the DNA as well as a different domain which binds the machinery of the cell that is involved in transcribing the gene.

Who discovered cells and when?

The cell was first discovered by Robert Hooke in 1665 using a microscope. The first Cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s.

Major function of cell membrane and what is it made of?

The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins.

What is the main role of the cell membrane?

The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins.

What are amino acids?

The first thing you might be asking is, "What is an amino acid?" There are more than fifty, and each one of them is a little different. Amino acids are used in every cell of your body to build the proteins you need to survive. All organisms need some proteins, whether they are used in muscles or as simple structures in the cell membrane. Even though all organisms have differences, they still have one thing in common: the need for basic chemical building blocks.

What is the fluid mosaic model and how does this describe the cell?

The fluid-mosaic model describes the plasma membrane of animal cells. The plasma membrane that surrounds these cells has two layers (a bilayer) of phospholipids (fats with phosphorous attached), which at body temperature are like vegetable oil (fluid). And the structure of the plasma membrane supports the old saying, "Oil and water don't mix."

4 different kinds of lipids?

The four types of lipids are triglycerides, fatty acids, phospholipids, and sterols (cholesterol). Triglycerides are important for metabolism and production of energy. Fatty acids are used to make lipids in cells, attatch to phosphate groups to form phospholipids, and they are used for storage. Phospholipids are the main part of cell membranes and assist in regulating cell environment. Sterols are an essential component for plant membranes.

2 parts of cell theory?

The generally accepted parts of modern cell theory include: All known living things are made up of one or more cells. All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms.

Saturated vs unsaturated fats?

The human body needs both saturated fats and unsaturated fats to remain healthy. Most dietary recommendations suggest that, of the daily intake of fat, a higher proportion should be from unsaturated fats, as they are thought to promote good cholesterol and help prevent cardiovascular disease, whereas an overabundance of saturated fats is thought to promote bad cholesterol. However, a few studies have found that little evidence for a strong link between the consumption of saturated fat and cardiovascular disease. Note: It is technically more accurate to call saturated and unsaturated fats types of fatty acids, as it is specifically the fatty acid found in a fat that is either saturated or unsaturated. However, referring to fatty acids as fats is common. Comparison chart Saturated Fats Unsaturated Fats Type of bonds (S) Consist of SINGLE bond (US) Consist of at least 1 DOUBLE bond

What is ATP/ADP? Why is it important?

The major energy currency molecule of the cell, ATP, is evaluated in the context of creationism. This complex molecule is critical for all life from the simplest to the most complex. It is only one of millions of enormously intricate nanomachines that needs to have been designed in order for life to exist on earth. This motor is an excellent example of irreducible complexity because it is necessary in its entirety in order for even the simplest form of life to survive.

Different classes of membrane proteins?

The structure of membrane proteins often determines their function. This, in turn, is the way we classify the type of membrane protein. In general, integral proteins are embedded within the hydrophobic layer of the membranes. Peripheral proteins are not embedded within the hydrophobic region of the membrane. Instead, they are associated with the hydrophilic heads or with an integral membrane protein.

What are the 3 domains?

The tree shows the separation of living organisms into three domains: Bacteria, Archaea, and Eukarya. Bacteria and Archaea are prokaryotes, single-celled organisms lacking intracellular organelles.

Review types of bonds and how are they different (polar, covalent, ionic)?

There are many types of chemical bonds and forces that bind molecules together. The two most basic types of bonds are characterized as either ionic or covalent. In ionic bonding, atoms transfer electrons to each other. Ionic bonds require at least one electron donor and one electron acceptor. In contrast, atoms with the same electronegativity share electrons in covalent bonds, because neither atom preferentially attracts or repels the shared electrons.

Which types of molecules can pass directly across the membrane? What kinds cannot? Give examples of each.

Three types of transporters have been identified. Uniporters transport one molecule at a time down a concentration gradient. This type of transporter, for example, moves glucose or amino acids across the plasma membrane into mammalian cells. In contrast, antiporters and symporters couple the movement of one type of ion or molecule against its concentration gradient to the movement of a different ion or molecule down its concentration gradient.

Acids and bases and how do they work?

To speak of acid or base strength, we need scales for acidity and basicity. pH and pOH scales are quantitative representations of these values for acidic and basic solutions. Next, we will define the acid dissociation constant, K a, and the base dissociation constant, K b, to quantify the strengths of particular acids and bases. These terms allow us to process acid and base strength mathematically and package them into values that we can gage conceptually. Using reference values, we can then see that a solution with pH 6 is weakly acidic, since it is slightly lower in pH than water at pH 7.

T/F: Chloroplasts have grana and stroma

True

Roles of each type?

Type of Compound Elements It Contains Examples Carbohydrates Carbon, hydrogen, oxygen Glucose, Starch, Glycogen Lipids Carbon, hydrogen, oxygen Cholesterol, Triglycerides (fats) Phospholipids Proteins Carbon, hydrogen, oxygen, nitrogen, sulfur Enzymes, Antibodies Nucleic Acids Carbon, hydrogen, oxygen, nitrogen, phosphorus Deoxyribonucleic acid (DNA) Ribonucleic acid (RNA) This table lists the four types of organic compounds, the elements they contain, and examples of each type of compound.

What is passive transport?

While active transport requires energy and work, passive transport does not. There are several different types of this easy movement of molecules. It could be as simple as molecules moving freely such as osmosis or diffusion. You may also see proteins in the cell membrane that act as channels to help the movement along. And of course there is an in-between transport process where very small molecules are able to cross a semi-permeable membrane.

Cell walls--- which cells have them? What are they?

While cell membranes might be around every cell, cell walls made of cellulose are only found around plant cells. Cell walls are made of specialized sugars called cellulose. Cellulose provides a protected framework for a plant cell to survive. It's like taking a water balloon and putting it in a cardboard box. The balloon is protected from the outside world. Cellulose is called a structural carbohydrate (complex sugar) because it is used in protection and support. Cell walls also help a plant keep its shape.

Parts that make up a phospholipid? How are they arranged to form a cell membrane?

Your body is a complicated machine, so you may be surprised to learn that important biological molecules that make up living things fall into only four main classes: carbohydrates, lipids, proteins, and nucleic acids. Your cells are surrounded by a very important type of lipid, called phospholipids. Phospholipids consist of a hydrophilic ('water loving') head and a hydrophobic ('water fearing') tail. Phospholipids like to line up and arrange themselves into two parallel layers, called a phospholipid bilayer. This layer makes up your cell membranes and is critical to a cell's ability to function.

Why are phospholipids important? Their structure?

Your body is a complicated machine, so you may be surprised to learn that important biological molecules that make up living things fall into only four main classes: carbohydrates, lipids, proteins, and nucleic acids. Your cells are surrounded by a very important type of lipid, called phospholipids. Phospholipids consist of a hydrophilic ('water loving') head and a hydrophobic ('water fearing') tail. Phospholipids like to line up and arrange themselves into two parallel layers, called a phospholipid bilayer. This layer makes up your cell membranes and is critical to a cell's ability to function.

Concentration gradient? When do substances follow the gradient? When do they go against the gradient?

a measurement of how the concentration of something changes from one place to another.

Primary function and location of each organ in PIG?

head (cranial) region neck (cervical) region trunk region (thoracic region) tail (caudal) region (abdomoninal region) Head: Find the following: pinna (auricle): external ear external nares (nostrils) upper and lower eyelids nictitating membrane (third eyelid)