Biology Module 1

A hypotheses in biology is described as-

A possible explanation of an observation

A scientific theory is

A statement of how the world works that is supported by experimental data

Properties of Life

All living organisms share several key characteristics or functions: order, sensitivity or response to the environment, reproduction, growth and development, regulation, homeostasis, and energy processing. When viewed together, these characteristics serve to define life.

Energy Processing

All organisms use a source of energy for their metabolic activities. Some organisms capture energy from the sun and convert it into chemical energy in food (photosynthesis); others use chemical energy in molecules they take in as food (cellular respiration).

Population

All the individuals of a species living within a specific area are collectively called a population. For example, a forest may include many pine trees. All of these pine trees represent the population of pine trees in this forest. Different populations may live in the same specific area. For example, the forest with the pine trees includes populations of flowering plants and also insects and microbial populations.

In an experiment the portion of the test to which the experimental variable is not applied is called the?

Control Group

If all reptiles give birth to their young by eggs, a science college finds a reptile that does not give birth its offspring via eggs. You conclude that this animal is not a reptile. This is an example of?

Deductive Reasoning

Regulation

Even the smallest organisms are complex and require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses. Two examples of internal functions regulated in an organism are nutrient transport and blood flow. Organs (groups of tissues working together) perform specific functions, such as carrying oxygen throughout the body, removing wastes, delivering nutrients to every cell, and cooling the body.

In an experiment the dependent variable is measured in the Experimental group only.

False

Homeostasis

In order to function properly, cells need to have appropriate conditions such as proper temperature, pH, and appropriate concentration of diverse chemicals. These conditions may, however, change from one moment to the next. Organisms are able to maintain internal conditions within a narrow range almost constantly, despite environmental changes, through homeostasis (literally, "steady state")—the ability of an organism to maintain constant internal conditions. For example, an organism needs to regulate body temperature through a process known as thermoregulation. Organisms that live in cold climates, such as the polar bear (Figure 4), have body structures that help them withstand low temperatures and conserve body heat. Structures that aid in this type of insulation include fur, feathers, blubber, and fat. In hot climates, organisms have methods (such as perspiration in humans or panting in dogs) that help them to shed excess body heat.

You pick up a pen and then release it and you observe that it drops and repeat this process a hundred times. You conclude that all things consisting of mass will therefore drop and call this force gravity. This is an example of?

Inductive Reasoning

Order

Organisms are highly organized, coordinated structures that consist of one or more cells. Even very simple, single-celled organisms are remarkably complex: inside each cell, atoms make up molecules; these in turn make up cell organelles and other cellular inclusions. In multicellular organisms (Figure 1), similar cells form tissues. Tissues, in turn, collaborate to create organs (body structures with a distinct function). Organs work together to form organ systems.

Growth and Development

Organisms grow and develop following specific instructions coded for by their genes. These genes provide instructions that will direct cellular growth and development, ensuring that a species' young (Figure 3) will grow up to exhibit many of the same characteristics as its parents.

Sensitivity or Response to Stimuli

Organisms respond to diverse stimuli. For example, plants can bend toward a source of light, climb on fences and walls, or respond to touch (Figure 2). Even tiny bacteria can move toward or away from chemicals (a process called chemotaxis) or light (phototaxis). Movement toward a stimulus is considered a positive response, while movement away from a stimulus is considered a negative response.

Protista and bacteria are grouped in different domains because

Protista have a membrane bounded nucleus and bacteria don't.

Reproduction

Single-celled organisms reproduce by first duplicating their DNA, and then dividing it equally as the cell prepares to divide to form two new cells. Multicellular organisms often produce specialized reproductive germline cells that will form new individuals. When reproduction occurs, genes containing DNA are passed along to an organism's offspring. These genes ensure that the offspring will belong to the same species and will have similar characteristics, such as size and shape.

Jon one of the best scientists at his university has proven that feeding mice peanuts makes them stronger. Because peanuts are high in protein he has set up an experiment where one group of 100 mice is fed normal food with large additions of peanuts, the second group of 5 mice is fed just normal food. His data shows that mice fed with large increases in protein had tails that were on average one and a half times longer. For which of the following reasons might this experiments results and conclusions be attacked or doubted?

Tail length is a poor measurement of strength

The difference between the control group and experimental group in an experiment is:

The independent variable is applied to the experimental group while not applied to the control group

A student doing research at UVU wished to determine if stress management classes really do help students do better on grades. She enrolled 20 volunteer students in a stress management class with another 20 just taking their regularly scheduled classes. She had the students conduct a survey indicating if they really did feel less stressed over the semester. The grades of the students were tabulated and compared to how much stress the students said they felt.In this experiment the control group would be? In this experiment what would the experimental or independent variable be? (refer to the previous experiment)

The stress management class

A student doing research at UVU wished to determine if stress management classes really do help students do better on grades. She enrolled 20 volunteer students in a stress management class with another 20 just taking their regularly scheduled classes. She had the students conduct a survey indicating if they really did feel less stressed over the semester. The grades of the students were tabulated and compared to how much stress the students said they felt.In this experiment the control group would be?

The students with regular classes

A student doing research at UVU wished to determine if stress management classes really do help students do better on grades. She enrolled 20 volunteer students in a stress management class with another 20 just taking their regularly scheduled classes. She had the students conduct a survey indicating if they really did feel less stressed over the semester. The grades of the students were tabulated and compared to how much stress the students said they felt.In this experiment the control group would be? In this experiment what would be the dependent variable? (refer to the previous experiment)

The students' GPA

organs

are collections of tissues grouped together performing a common function. Organs are present not only in animals but also in plants.

Organisms

are individual living entities. For example, each tree in a forest is an organism. Single-celled prokaryotes and single-celled eukaryotes are also considered organisms and are typically referred to as microorganisms.

Prokaryotes

are single-celled or colonial organisms that do not have membrane-bound nuclei or organelles

organelles

are small structures that exist within cells. Examples of organelles include mitochondria and chloroplasts, which carry out indispensable functions: mitochondria produce energy to power the cell, while chloroplasts enable green plants to utilize the energy in sunlight to make sugars

ecosystem

consists of all the living things in a particular area together with the abiotic, non-living parts of that environment such as nitrogen in the soil or rain water.

eukaryotes

do have membrane-bound organelles and a membrane-bound nucleus.

eukaryotic cell

is a cell that has a membrane-bound nucleus and other membrane-bound compartments or sacs, called organelles, which have specialized functions. The word eukaryotic means "true kernel" or "true nucleus," alluding to the presence of the membrane-bound nucleus in these cells. The word "organelle" means "little organ," and, as we learned earlier, organelles have specialized cellular functions, just as the organs of your body have specialized functions.

molecule

is a chemical structure consisting of at least two atoms held together by one or more chemical bonds.

organ system

is a higher level of organization that consists of functionally related organs. Mammals have many organ systems. For instance, the circulatory system transports blood through the body and to and from the lungs; it includes organs such as the heart and blood vessels

prokaryotic cell

is a simple, single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle. We will shortly come to see that this is significantly different in eukaryotes. Prokaryotic DNA is found in the central part of the cell: a darkened region called the nucleoid (Figure 1).

biosphere

is the collection of all ecosystems, and it represents the zones of life on earth. It includes land, water, and even the atmosphere to a certain extent.

Biology

is the science that studies life

Atom

is the smallest and most fundamental unit of matter. It consists of a nucleus surrounded by electrons. Atoms form molecules.

community

is the sum of populations inhabiting a particular area. For instance, all of the trees, flowers, insects, and other populations in a forest form the forest's community. Keep in mind that the community level only consists of living organisms. The forest itself is an ecosystem; this is the first level that contains non-living aspects of a given area that impact the living things in that environment.

cell

itself is the smallest fundamental unit of structure and function in living organisms.

macromolecules

large molecules that are typically formed by polymerization (a polymer is a large molecule that is made by combining smaller units called monomers, which are simpler than macromolecules). An example of a macromolecule is deoxyribonucleic acid (DNA) (Figure 1), which contains the instructions for the structure and functioning of all living organisms.

tissues

which are groups of similar cells carrying out similar or related functions