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3 years ago

How does the cell recognize that lactose needs to be metabolized?

1 answer:

3 0

Lactose metabolism is regulated by lac operon in prokaryotic cells. When in the environment lactose is present, the cell signals the presence of lactose and synthesizes the enzyme required for the degradation of lactose. Removal of lactose from the environment leads to the termination of the enzyme synthesis. Thus, the metabolism of lactose is environment dependent.

The metabolism of lactose is also dependent on the presence of glucose. Glucose is the favorite food for bacteria. If glucose and lactose both are present in the environment, the bacterial cells prefer glucose over lactose and lactose is not metabolized. In the absence of glucose, the cells will metabolize lactose.

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Newborn twin girls delivered in the hospital via cesarean section at 27 weeks, weighing 850 grams for twin a and 900 grams for t

Rudik [331]

The answers is code 765.03. There’s an assigned code for the birth of an infant from a categories V30-V39, this is according to the type of birth and from that series there is assigned as principal diagnosis. Assigned only once to a new born at the time of birth. Code 765.03 is assigned for extreme immaturity with weight between 750-999 grams.

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3 years ago

How much of the protein consumed by humans around the world is fish?

notsponge [240]

The correct answer is: about 20 percent.

Fish is one of the major sources of animal protein around the world. This is especially case for the people who live on the coast.

Other source of the animal protein is red meat. About 70 percent comes from animals such as cows, goats, sheep, buffalo, deer.

When it comes to non-meat protein food, eggs and dairy products provide good energy source.

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3 years ago

Read 2 more answers

What are cytokines; what role do they play in cancer treatment? Give an example of one in your answer.

ludmilkaskok [199]

Answer and Explanation:

Cytokines is the molecule which has the ability to communicate with the immune system cells to target on antigen by generating a response. It is mostly comprised of protein in a group along with peptides.

They are involved in the cancer treatment by production of the signalling molecules that gets involved in the method of stimulating and mobilize the immune system and thus cytokines come into the action for preventing the cancer by providing anti-inflammatory action,anti-cancer cell etc.

<u>Example</u>- In case of ovarian cancer,there is the majority of the immuno-suppressive action and thus there is production of the anti-inflammatory cytokines and thus maintain the immune system.

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3 years ago

Question 4

Dvinal [7]

Answer:

Oxygen

Explanation:

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3 years ago

Match the function or location to the correct connective tissue. Allows the growth of long bones Intervertebral discs, pubic sym

pychu [463]

Answer:

<h3>Allows the growth of long bones</h3>

Hyaline cartilage

Hyaline cartilage allows growth of long bones by endochondral ossification, which involves <u>replacement of the initial hyaline cartilage models to bony tissue</u>. This <em>model</em> is <em><u>glass-like</u></em> and formed from the <u>combination of chondroitin sulfate and type II collagen</u>. Aside from bone growth, it's also seen in joints, anterior ends of ribs, upper respiratory tract like larynx, trachea, and bronchi.

<h3>Intervertebral disks, pubic symphysis</h3>

Fibrocartilage

Fibrocartilage is composed of<u> Type 1 and 2 collagen</u>, which contributes to the toughness of this tissue. It is present in these sites due to the dynamic nature of these body parts. This cartilage is able to w<u>ithstand a certain amount of shear and compressive forces</u>. Along with the hyaline cartilage, it also <u>promotes bone formation.</u>

<h3>External ear, epiglottis, and auditory tubes </h3>

Elastic cartilage

Elastic cartilage, or yellow cartilage contains a number of elastic fiber and collagen. Elastin is the primary protein in this tissue, which contributes to the <u>elasticity and flexibility</u> of the above body parts. If observed under the microscope, its structure is same to hyaline but has numerous yellow elastic fibers present, which appear as a dark streak.

<h3>Outer portion of all bones</h3>

Compact bone

Compact bone or cortical bone, is the substance used to form the solid outside structure of the bones.

<h3>Inside skull bones, vertebrae, and sternum</h3>

Spongy bone

Cancellous bone, spongy bone, or trabecular bone is mostly found in the long bones, <u>covered by compact bone</u>. The bone is sponge-like in structure because it <u>houses the blood vessels inside the bones.</u>

<h3>Transports oxygen, carbon dioxide, and other substances</h3>

Blood

Blood is a connective tissue composed of red blood cells (erythrocytes), white blood cells (leukocytes), and platelets. It also connects bodily systems by t<u>ransporting nutrients, hormones, and chemical messengers, etc.</u>

<h3>Produces new blood cells and stores lipids</h3>

Bone marrow

Bone marrow is found <u>within the spongy bone</u> which houses the young blood cells until they are ready for use by the body or also called hematopoiesis.

<h3>Capable of strength with stretching and recoil in several directions</h3>

Dense irregular elastic connective tissue

For dense irregular elastic connective tissue, the elastic fibers are arranged randomly. This makes the organ <u>stretchable and</u> <u>flexible in all directions and able to return to its original shape</u>. An example of this is the dermis.

<h3>Tensile strength capable of withstanding stretch in all directions</h3>

Dense irregular collagenous connective tissue

Its fibers are also arranged in random but with fibrous tissue. It is also <u>flexible and tougher</u> compared to dense irregular elastic connective tissue. It is usually found in <u>fibrous capsule of joints and muscle fascia.</u>

<h3>Vocal folds and ligaments between vertebrae</h3>

Dense regular elastic connective tissue

For dense regular elastic connective tissue, the elastic fibers are <u>arranged in parallel</u>. It enhances the present tensile strength to a specific direction wherein the fiber is oriented.

<h3>Tendons and ligaments</h3>

Dense regular collagenous connective tissue

For dense regular collagenous connective tissue, the collagen fibers are also arranged in parallel. Tensile strength and resistance is enhanced to a specific direction wherein the fiber is oriented. The role of these tissues is to <u>transfer forces to the bone to avoid injury.</u>

<h3>Provides superstructure for lymphatic tissues</h3>

Reticular tissue

Reticular tissue is found <u>mostly with numerous amounts of cells</u>. They are composed of <em>Type 3 collagen fibrils</em> and is <em>net-like</em> in appearance, also called <em>"reticulum" </em>due to the fiber arrangement (<em>reticulin</em>). They act as a <u>scaffold of the organ/s they cover.</u>

<h3>Energy storage</h3>

Adipose tissue

Adipose tissue is composed of fat cells or adipocytes. It also functions to <u>insulate and cushion</u> the body from hard surfaces.

<h3>Epithelial basement membrane sits on this</h3>

Loose connective tissue

Loose connective tissue or<u> areolar connective tissue</u>, contains a <u>lot of cells, ground matter, and spaces in between it</u>, coining the "loose" in its name. Fibroblasts, collagen fibers, and matrix, etc., are found in almost every part of the body. This helps in <u>keeping the organs in place and some slight tough protection. </u>

<h3>Precursor to adult connective tissues</h3>

Mesenchymal tissue

Mesenchymal tissue <u>forms the body’s connective tissues</u>, from bones, cartilage, to the organ systems. It is found <u>abundant in the development of fetal tissues.</u>

<h3>Umbilical cord of the newborn</h3>

Mucous connective tissue

Mucous connective tissue is also found <u>during development of the embryo</u>. Due to <u>mucoproteins</u>, it resembles a mucus-like substance, as in <u>Wharton's jelly found in the umbilical cord</u> and <u>vitreous in the eyeball.</u>

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3 years ago